Utility of intercostal artery perforator flap in granulomatous lobular mastitis: a single-center retrospective study

Introduction

Granulomatous lobular mastitis (GLM) is a rare chronic inflammatory disease that occurs in the breast lobules. There has been a marked increase in GLM incidence, with a particularly notable increase reported in European regions and developing countries, including China (1). While its etiology remains largely unclear, emerging evidence suggests that obstructed lactiferous ducts, hyperprolactinemia, smoking, diabetes, infection, and autoimmune diseases are all contributing factors (2-4). Despite being a benign disease, GLM can severely affect patients’ health and quality of life. Specifically, palpable and painful breast lumps and inflammatory changes are the typical initial manifestations, but the lesions gradually progress to abscesses, skin ulcers, scars, sinus tracts, and nipple retraction as GLM progresses. Although a previous population-based study of non-lactational mastitis discussed breast cancer risk (5), GLM itself remains a benign inflammatory disease, and the more immediate clinical issue is that GLM may mimic breast malignancy clinically and radiologically. Furthermore, GLM progresses rapidly, with a recurrent or prolonged natural course (6). Patients often endure a disease course of approximately 6–12 months, as well as breast shape changes caused by GLM, which impose adverse physical, psychological, and economic burdens on patients.

Definitive diagnosis is often challenging because the clinical manifestations and radiographic images of GLM are similar to those of breast cancer, acute or chronic infections, and inflammatory diseases. Moreover, no consensus on case management and no gold-standardized treatment protocol for GLM are currently available, so the clinical methods are diversified, including close observation, medication therapy, and operative interventions (7-9). Drug-based conservative treatments, such as corticosteroids, immunosuppressants, anti-tuberculosis drugs, antibiotics, and traditional Chinese medicine, are adopted as primary treatment modalities in many countries, but their clinical application is often limited because of the toxic side effects on patients' health after long-term medication (10-12). For relapsing GLM or when conservative treatments are inefficient or when patients show poor compliance with drug use, operative interventions could be recommended and are essential to achieve good recovery rates (13,14).

Clinically, the available operative interventions include simple lump excision, extended mass resection, and breast segmentectomy. A few patients have to undergo multiple operations due to recurrence, and one of the critical factors for reducing recurrence is complete removal of the entire lesion (7,15). Extended mass resection and breast segmentectomy have been widely used for GLM; however, surgery often leads to large breast tissue defects, resulting in unfavorable cosmetic results and psychological burdens. In such patients, breast deformity can be partly corrected using a random breast dermo-glandular flap, which is a pedicle flap involving cutaneous, subcutaneous, and mammary gland tissues (16,17). However, the T-shaped, pear-shaped, and butterfly-shaped incisions used in breast dermo-glandular flap-based surgery would leave obvious postoperative scars on the breast skin and affect breast appearance. Moreover, these procedures seem to be suitable for women with large breasts, but for most Asian women and a small number of Western women with smaller breasts, such surgery is not appropriate. Likewise, advancement flap, rotation skin flap, and latissimus dorsi flap would also leave extensive scars (13). Determining a procedure to fill surgical defects, maintain breast shape, and hide surgical incisions in GLM patients is a significant challenge for breast surgeons.

Intercostal artery perforator (ICAP) flaps are one of the volume replacement oncoplastic techniques that could be used after breast-conserving surgery to fix challenging defects in a relatively large tumor-to-breast ratio or small-to-moderate-sized breast (18). At our center, we offered these flaps to GLM patients with challenging defects. To date, no previous study has compared extended mass resection and breast defect reconstruction with an ICAP flap in GLM patients, making this study the first to propose the use of an ICAP flap to treat GLM. Hence, this study aimed to evaluate the efficacy and patient satisfaction of the ICAP flap, hoping to offer new ideas for the clinical management of GLM. We present this article in accordance with the STROCSS reporting checklist (19) (available at https://gs.amegroups.com/article/view/10.21037/gs-2026-0168/rc).

Methods

Study design and patient enrollment

This was a retrospective cohort study of GLM patients treated surgically between January 2022 and May 2024 at Changzhou No. 2 People’s Hospital, the Third Affiliated Hospital of Nanjing Medical University. The present study was approved by the ethics committee of Changzhou No. 2 People’s Hospital, the Third Affiliated Hospital of Nanjing Medical University (No. KY204-01). The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. Written informed consent was obtained from all patients.

At our center, priority recommendations for treatment-naive GLM patients without abscesses include oral corticosteroids and antibiotics (20). If the GLM is improved or cured, patients are observed. Abscess drainage was applied to treatment-naive GLM patients with abscesses. For relapsing GLM or when conservative treatments are inefficient or when patients show poor compliance with drug use, they were proposed to participate in this study. Specifically, patients were enrolled if they met the following criteria: (I) age over 18 years and complete medical history; (II) pathological diagnosis of GLM by core needle biopsy; (III) single GLM lesion or multiple lesions occupying less than three-fourth quadrants of the ipsilateral breast; (IV) having at least one of the following conditions: (i) refractory to conservative treatments including close observation and medication therapy for at least 2 weeks; (ii) recurrence after abscess drainage or fistula removal; (iii) recurrence after inflammatory lesion removal, including simple lump excision and extended mass resection; and (V) no serious comorbidities. The exclusion criteria were as follows: (I) acute infection or tuberculosis; (I) inflammatory lesions occupying nearly all quadrants of the ipsilateral breast; (III) pregnancy or lactation; (IV) pathological diagnosis of breast cancer; (V) serious comorbidities; (VI) other potential granulomatous diseases, such as Wegener’s granulomatosis, sarcoid-like granulomatous reactions, and foreign body granulomas; or (VII) refusal to participate.

Based on the above criteria, 108 patients were finally included in the study (Figure 1). Patients’ characteristics are detailed in Table 1. These patients were thoroughly informed about the study design and were grouped according to the actual surgical strategy selected in routine clinical practice after clinical evaluation and shared decision-making: Group A, extended mass resection and breast defect reconstruction with an ICAP flap (flap reconstruction group, 43 patients); Group B, extended mass resection without breast defect reconstruction (no reconstruction group, 37 patients); and Group C, no resection but continued with abscess drainage or fistula removal (no resection group, 28 patients). Because drainage or fistula removal follows a different treatment philosophy from extended mass resection, Group C was retained as an exploratory real-world reference group rather than a strictly equivalent comparator.

Figure 1 Flow diagram of patient enrollment. GLM, granulomatous lobular mastitis; ICAP, intercostal artery perforator.

Surgical procedures

The extent of GLM lesions was evaluated using ultrasonography (Figure 2A) and mammography (Figure 2B), and magnetic resonance imaging was suggested in patients with multiple lesions when necessary. In selected patients, mapping and marking of the ICAP after imaging and identification by Doppler were also performed pre-operatively (Figure 2C). All surgeries were performed under general anesthesia by the same team comprising one professor, one fellow, and one resident, and patients were placed in a supine position. Surface projection of the GLM was marked on the skin (Figure 3A), and the nearest periareolar incision to the lesion was chosen (Figure 3B). If there were multiple lesions, a periareolar incision was chosen by considering the location of the majority of GLM. Occasionally, an arc or radial incision along the skin dermatoglyph above the pathological changes in the breast is used. The incision length was determined according to the distance from the GLM to the areola and the GLM size. Then, the entire lesion was removed thoroughly, including the abscess, fistula, necrotic tissues, and surrounding inflammatory area, thus achieving a clear margin in the breast defect based on histological results (Figure 3C). The surgical cavity was repeatedly washed with hydrogen peroxide, povidone-iodine, and saline, and the incisions were closed in anatomical layers (Figure 3D).

Figure 2 Evaluation of GLM lesion and mapping of ICAP. (A) The GLM lesion appeared as an irregularly bordered, heterogeneous echoic area on ultrasound. (B) Mammography showed an asymmetrical dense shadow below the breast with an irregular margin. (C) Mapping and marking of the ICAP after imaging and identification by Doppler were performed pre-operatively. GLM, granulomatous lobular mastitis; ICAP, intercostal artery perforator.

Figure 3 Surgical procedures of extended mass resection and breast defect reconstruction with a LICAP flap. (A) The surgical area was checked, and the surface projection of the mass was marked on the skin. (B) Dominant perforators were located preoperatively. (C) The entire lesion and surrounding tissues were removed. (D) The surgical cavity was repeatedly washed with hydrogen peroxide, povidone-iodine, and saline. (E) The LICAP flap was harvested based on the surgical defect. (F) The LICAP flap was inserted into the surgical defect, ensuring protection of the vascular pedicle and flap perfusion. (G) Inframammary fold incision was lifted and attached to the chest wall. (H) A drainage tube was placed, and incisions were closed in layers. LICAP, lateral intercostal artery perforator.

In selected patients, the ICAP flap was designed and harvested using an inframammary fold incision. Following the skin incision, the dissection started from the lowest flap point and continued in a direction from inferior to superior (Figure 3E). After full mobilization, the perforator was carefully dissected and even skeletonized to ensure that the entire flap could be inserted into the surgical defect without tension or pedicle deformation (Figure 3F). Other non-essential perforators were sometimes sacrificed to achieve an additional flap rotation length. Then, the ICAP flap was de-epithelialized, and its blood supply was rechecked intraoperatively by a hand-held Doppler. After repairing the surgical defects, the flap edge was secured to the pectoral fascia by using 2/0 Vicryl sutures. Remarkably, the lower edge of the inframammary fold incision was lifted and attached to the chest wall with interrupted 2/0 PDS sutures, thus preventing inframammary fold migration and distortion (Figure 3G). Finally, one drainage tube was placed in the operation area, and all incisions were closed in layers (Figure 3H). The drainage tube was removed when the discharge volume was less than 10 mL for three consecutive days. Based on GLM location and extension, these patients were further stratified into three subgroups, and the selected ICAP flap was used (21).

The choice of ICAP flap was determined by lesion location, estimated defect volume after resection, breast size, skin and soft-tissue condition, and the amount of redundant tissue along the inframammary fold or lateral chest wall. LICAP flaps were preferentially used for lateral or lower-lateral defects, whereas AICAP or MICAP flaps were selected for lower, central, or medial defects. Combined ICAP flaps were considered when a single flap was insufficient to fill a large or multifocal defect. Dominant perforators were identified preoperatively by imaging and Doppler mapping and were confirmed intraoperatively according to pulsation, flap perfusion, pedicle length, rotation arc, and absence of tension or torsion after transposition. Exact defect size, flap dimensions, perforator diameter, and flap harvest time were not uniformly recorded in this retrospective cohort; therefore, these parameters should be prospectively collected in future studies.

Selected ICAP flap

Pattern 1: lateral ICAP (LICAP) flap for 27 patients

LICAP originates from the costal segment of the intercostal vessels and is generally observed at the largest branch in the sixth intercostal space. Literature review shows that LICAP is approximately 0.8 to 3.5 cm anterior to the latissimus dorsi. The LICAP flap can fix defects in the outer quadrant of the breast (22) (Figure 3).

Pattern 2: anterior ICAP (AICAP)/medial ICAP (MICAP) flap for 12 patients

AICAP arises from the anterior intercostal artery and passes through the rectus abdominis muscle. It was revealed that the AICAP could be located within 1 to 3 cm lateral to the sternal border. The AICAP flap uses soft tissue excess below the inframammary fold and covers defects over the entire lower mammary pole (23) (Figure 4A).

Figure 4 Simple operative steps of the AICAP/MICAP flap and ICAP flap combination. Simple operative steps included marking of the surgical area and extent, locating of dominant perforators, resection of GLM lesion, estimation of flap harvest size, design of an AICAP/MICAP flap (A) or ICAP flap combination (B), transfer of flap to surgical defect, de-epithelization of flap skin, and shaping using the healthy breast as a reference. AICAP, anterior ICAP; granulomatous lobular mastitis; ICAP, intercostal artery perforator; MICAP, medial ICAP.

MICAP flap, based on perforators arising from the internal mammary or anterior intercostal vessels, is used for the repair of medial inferior and central breast defects where there is sufficient soft tissue below the inframammary fold (24) (Figure 4A).

Pattern 3: ICAP flap combination for 4 patients

When the above patterns are unable to be fixed, or multiple lesions occupy nearly three-fourths of the ipsilateral breast, different ICAP flaps are employed to ensure better flap perfusion and breast appearance (25) (Figure 4B).

Assessment indicators and follow-up

First, preoperative patients’ characteristics, including age, body mass index, disease duration, clinical manifestations, treatment history, and concomitant medical conditions, were reviewed. Second, intraoperative records, including surgery time and blood loss, were obtained. Third, postoperative details, including drainage volume, drainage removal time, delayed wound healing, positive bacterial culture, subcutaneous fat liquefaction, incision infection, nipple-areola ischemic necrosis, ecchymosis, and hematoma, were collected. Fourth, patient-reported outcomes, including dressing change and bathing, cosmetic change, and recurrence, were documented. Specifically, the breast cosmetic evaluation was based on the postoperative shape compared with the preoperative condition. Dressing change and bathing and changes in breast appearance were self-evaluated as “better”, “same”, or “worse”. Recurrence was defined as GLM relapse in the same surgical area evaluated by physical examination combined with ultrasonography and/or mammography during the follow-up period. To pay more attention to patients’ subjective feelings, a “patient satisfaction questionnaire” developed by Wang et al. was also used in the present study (8,13).

Statistical analysis

Statistical analyses were performed using IBM SPSS (version 27.0; SPSS Inc., Chicago, IL, USA). Normality of data distribution was assessed using the Kolmogorov-Smirnov test. Categorical variables were presented as numbers and percentages. Continuous variables were presented as mean ± standard deviation (or median and quartile when necessary). Pearson’s chi-square test or Fisher’s exact test was used to compare categorical variables. One-way analysis of variance with Bonferroni correction was applied for normally distributed variables, while the Kruskal-Wallis test was used for non-normally distributed data. No formal sample size calculation was performed because of the retrospective exploratory design. The clinically relevant resection-based comparison focused on Group A and Group B, while Group C was retained as an exploratory reference reflecting a different real-world treatment pathway. Pairwise and multi-group comparisons were interpreted cautiously because of multiple testing and the non-randomized study design. Statistical significance was set at P<0.05.

Results

Preoperative patients’ characteristics

A total of 236 female patients were diagnosed with GLM between January 2022 and May 2024. Of these treatment-naive GLM patients, 71 (30.1%) responded to conservative treatments such as oral corticosteroids and antibiotics, 43 (18.2%) were cured after abscess drainage, and 122 (51.7%) required further surgery and were initially selected. Three patients were lost during follow-up, and 11 patients chose traditional Chinese medicine after surgery. A total of 108 patients were finally included in this study. A flow diagram of patient enrollment is shown in Figure 1.

Preoperative patients’ characteristics are shown in Table 1. Mean age was 43.08±8.86 years old, mean body mass index was 25.81±3.54 kg/m², and mean disease duration was 34.15±7.71 days. Analysis of clinical manifestations revealed that 96 (88.89%) patients had a large breast mass (>3 cm), 13 (12.04%) had nipple discharge, 45 (41.67%) had abscess, 11 (10.19%) had skin ulceration, and 14 (12.96%) had ductal fistulas. A total of 58 (53.70%) patients had a treatment history of corticosteroids, 90 (83.33%) had antibiotics, and 27 (25.00%) had abscess drainage. Concomitant medical conditions, including prolactinoma (5.56%), psychotropics (6.48%), trauma within 1 month (0.93%), smoking (4.63%), drinking (8.33%), autoimmune diseases (1.85%), polycystic ovarian syndrome (0.93%), hypertension (14.81%), and diabetes mellitus (7.41%) were also recorded. There were no significant differences in the demographic data, clinical manifestations, treatment history, and concomitant medical conditions among the three groups (all P>0.05).

Operative-associated data

Before surgery, the extent of the GLM lesion was carefully checked using ultrasonography and mammography, and magnetic resonance imaging was recommended in patients with multiple lesions when necessary. An example of a GLM is shown in Figure 2, which shows an irregularly bordered, heterogeneous echoic area (Figure 2A). Mammography showed an asymmetrical dense shadow below the breast with an irregular margin (Figure 2B). The surface projection of the GLM was then marked on the skin, and the nearest periareolar incision to the lesion was determined. Occasionally, an arc or radial incision is used when necessary. In selected patients, mapping and marking of the perforators after imaging and identification by Doppler were performed (Figure 2C).

The patients were grouped and analyzed according to the actual surgical strategy received in routine clinical practice. Specifically, 43 patients in Group A underwent extended mass resection and breast defect reconstruction with an ICAP flap (flap reconstruction group), 37 patients in Group B underwent extended mass resection without breast defect reconstruction (no reconstruction group), and 28 patients in Group C continued with abscess drainage or fistula removal without mass resection (no resection group). Operative-associated data are presented in Table 2. The median surgery times in Group A, Group B, and Group C were 95, 50, and 40 min, respectively. Blood loss in Group A, Group B, and Group C was 62, 42, and 29 mL, respectively. The drainage volumes in Group A, Group B, and Group C were 109, 68, and 35 mL, respectively. In addition, the drainage removal times in Group A, Group B, and Group C were 14, 8, and 7 days, respectively. Analysis of these intraoperative records and postoperative details indicated that surgery times, blood loss, drainage volumes, and drainage removal times differed significantly among the three groups (all P<0.001). However, there were no significant differences in delayed wound healing, positive bacterial culture, subcutaneous fat liquefaction, incision infection, nipple-areola ischemic necrosis, ecchymosis, or hematoma among the three groups (all P>0.05).

Patient-reported outcomes

All patients were followed for 1 year. Analysis of the patient-reported outcomes (Table 3) revealed that 28 (25.93%), 70 (64.81%), and 10 (9.26%) patients, respectively, felt “better”, “same”, and “worse” in dressing change, with respect to the preoperative condition. Besides, about 25 (23.15%), 75 (69.44%), and 8 (7.41%) patients, respectively, reported “better”, “same”, and “worse” in bathing, when compared with the preoperative condition. Cosmetic change with respect to the preoperative condition was “better” in 48 (44.44%) patients, “same” in 30 (27.78%) patients, and “worse” in 30 (27.78%) patients. Remarkably, 39 (90.70%) patients in Group A experienced “better” (Figure 5), 3 (6.98%) patients felt “same”, and only one patient (2.32%) in Group A felt “worse” due to the “bird’s beak” deformity. The remaining “worse” cosmetic changes were mainly reported by 25 (67.56%) patients in Group B (Figure 6A) and 4 (14.29%) patients in Group C (P<0.001) (Figure 6B). Among the seven recurrences during the 1-year follow-up, one occurred in Group B and six occurred in Group C. No recurrence was observed in Group A; however, given the limited sample size and non-randomized design, this finding should be regarded as exploratory.

Figure 5 Preoperative and postoperative photos of a patient who underwent extended mass resection and breast defect reconstruction with a LICAP flap. (A) Preoperative view showing marking of GLM and flap harvest area. (B) Postoperative view at 1, 3, 6, and 12 months, showing near symmetry of both breasts with an aesthetically pleasing outcome. Surgical incision was located on the lateral chest and was well-concealed. GLM, granulomatous lobular mastitis; LICAP, lateral intercostal artery perforator.

Figure 6 Preoperative and postoperative photos of patients from no reconstruction group and no resection group. (A) An example of a patient who underwent extended mass resection without flap reconstruction, showing a large surgical defect. (B) An example of a patient who continued with abscess drainage or fistula removal without mass resection showing obvious scars.

In order to pay more attention to patients’ subjective feelings, all patients were asked to complete the “patient satisfaction questionnaire” (8,13). As shown in Table 4, there were no significant differences in economic costs among the three groups, whereas breast shape (P<0.001), treatment time (P=0.04), treatment effect (P<0.001), and quality of life (P<0.001) differed among the three groups. Analysis of these items indicated that the total satisfaction scores differed significantly among the three groups (P<0.001). Specifically, the total satisfaction score was higher in Group A than in Group B (P<0.001) and Group C (P<0.001), whereas the total scores were similar in Groups B and Group C (P=0.33). These results suggest that extended mass resection and breast defect reconstruction with an ICAP flap may improve patient-reported cosmetic satisfaction in selected GLM patients, while the exploratory comparison with the no resection group should be interpreted cautiously because of the different treatment strategy.

Discussion

GLM, a clinically challenging inflammatory breast disease, often presents as a suddenly developing breast lump with or without pain, which can rapidly progress to abscesses, skin ulcers, scars, sinus tracts, and nipple retraction. Consistent with previous reports, the most common manifestation in our cohort was a large breast mass observed in 88.89% of the patients (16,17). Owing to its clinical manifestations and imaging features resembling those of breast malignancy, a definitive diagnosis of GLM can only be made pathologically. If not promptly managed, GLM may affect breast appearance and impose physical, psychological, and economic burdens on patients. No standard treatment protocol is currently available, and GLM patients may require different treatment methods at different time points, such as close observation, medication therapy, abscess drainage, fistula management, and operative resection. At our center, priority recommendations for treatment-naive GLM patients without abscesses include oral corticosteroids and antibiotics; however, some cases show poor compliance with drug use due to the toxic side effects on health after long-term medication. These patients, along with relapsing cases and patients unresponsive to conservative treatments, were recommended to undergo surgery. In fact, 53.70% of patients in our cohort had a treatment history of corticosteroids, 83.33% of patients had antibiotics, and 25.00% of patients had abscess drainage.

We acknowledge that drainage or fistula removal represents a different treatment philosophy from extended mass resection. Nevertheless, we retained the no-resection group because it reflects a real-world treatment pathway used for refractory or recurrent GLM in routine practice and provides clinical context for less invasive local management. Therefore, the comparison between Group A and Group B is the most relevant comparison for evaluating the reconstructive value of the ICAP flap after resection, whereas Group C should be interpreted as an exploratory reference group rather than a strictly equivalent comparator.

To reduce recurrence, the entire mass and the surrounding inflammatory areas should be thoroughly removed. However, from a cosmetic perspective, wider resection is associated with larger tissue defects and a higher risk of breast deformity. Therefore, determining a procedure to fill surgical defects, maintain breast shape, and hide surgical incisions in GLM patients is an important challenge for breast surgeons. In this study, we retrospectively analyzed the feasibility and outcomes of ICAP flap reconstruction in selected GLM patients undergoing extended mass resection, using the no reconstruction group as the main resection-based comparator and the no resection group as an exploratory clinical reference. We found no significant differences in delayed wound healing, positive bacterial culture, subcutaneous fat liquefaction, incision infection, nipple-areola ischemic necrosis, ecchymosis, or hematoma among the three groups. Intraoperative records and postoperative details revealed longer surgery times and drainage removal times, as well as more blood loss and drainage volumes, in the flap reconstruction group than in the other groups, which is expected because flap reconstruction adds operative steps.

Compared with other oncoplastic approaches reported in the literature, ICAP flaps may offer several practical advantages for GLM patients with small-to-moderate-sized breasts or a relatively large defect-to-breast ratio. Random breast dermo-glandular flaps and volume-displacement procedures can be useful, but they often rely on adequate residual breast tissue and may leave more visible breast-skin scars. Latissimus dorsi flaps are reliable for larger defects but involve greater donor-site morbidity and a more extensive procedure. By contrast, ICAP flaps use local chest-wall perforator tissue, allow an incision hidden near the inframammary fold or lateral chest wall, and can be tailored to lateral, lower, central, or medial defects by selecting LICAP, AICAP, MICAP, or combined ICAP flaps. However, this study was not designed as a direct head-to-head comparison with other oncoplastic techniques, and the above comparison should be viewed as historical and contextual.

Orabi et al. reported a mean surgery time of 129.6±13.2 min in partial breast reconstruction using ICAP flaps during breast-conserving surgery (26), while Xie et al. reported 100.5±10.2 min (18). In contrast, our study showed a median surgery time of 95 min, including both extended GLM resection and breast defect reconstruction with ICAP flaps. Although we did not record the time to obtain and transplant the flap, harvesting, de-epithelialization, and remodelling have been reported to require a mean of 30 to 45 min for ICAP flaps (23,27), with more time potentially required for combined ICAP flaps. Familiarity with ICAP anatomy and standardized preoperative mapping may reduce operative uncertainty, but the learning curve remains important and should be further evaluated in prospective studies (28-31).

In this study, dressing change and bathing were “better” in 25.93% and 23.15% of patients, respectively, which reflected patients’ wound care experience and return to normal life. Dressing change and bathing were mainly reported to be “worse” in the no resection group, possibly because abscess drainage and fistula management may require prolonged wound care even when infection is controlled. In terms of cosmetic change, 90.70% of patients in the flap reconstruction group reported “better” outcomes. In contrast, 67.56% of patients in the no reconstruction group and 14.29% of patients in the no resection group reported “worse” cosmetic change, mainly due to surgical defects, breast deformity, and visible skin scars. The recurrence rate was lower in the two resection-based groups than in the no resection group. This finding most likely reflects complete lesion removal and repeated cavity lavage rather than the reconstructive flap itself. Therefore, the absence of recurrence in the flap reconstruction group should be considered an exploratory observation that requires confirmation with longer follow-up and larger prospective cohorts.

To comprehensively explore the significance of the ICAP flap in GLM patients and quantitatively evaluate patients’ subjective feelings, a “patient satisfaction questionnaire” reported by other researchers was used in the present study (8,13). There were no significant differences in economic costs among the three groups, whereas breast shape, treatment time, treatment effect, and quality of life differed among the three groups. The total satisfaction score was higher in the flap reconstruction group than in the no reconstruction group and the no resection group. The potential reasons for this difference may be that surgical resection could shorten the disease course and reduce pain, whereas the ICAP flap could repair surgical defects and minimize breast deformity. However, these outcomes were patient-reported and may be influenced by perception bias. We did not use BREAST-Q, objective breast symmetry measurements, or blinded panel assessment in this retrospective cohort; therefore, patient-reported cosmetic and satisfaction results should be interpreted with this limitation in mind.

Our study has some limitations. First, the sample size was relatively small and was obtained from a single center. Second, the patients in the present study were followed for only 1 year, which might not have been long enough because recurrence may occur after 1 year. Third, treatment choice considered patient preference and clinical judgment, resulting in potential selection bias. In particular, the no resection group followed a different treatment philosophy and should be interpreted as an exploratory real-world reference group rather than a strictly equivalent comparator to the two resection-based groups. Fourth, no unified standard for evaluating treatment efficacy in GLM patients is currently available, and we used patient-reported outcomes and satisfaction questionnaires based on previous publications. We did not use BREAST-Q, objective breast symmetry measurements, or blinded cosmetic assessment, which may introduce perception bias. Fifth, exact defect size, flap dimensions, perforator diameter, perforator number, and flap harvest time were not uniformly recorded in this retrospective cohort. Retrospective estimation of these parameters from non-standardized clinical photographs or operative notes could introduce measurement bias; therefore, future prospective studies should standardize the collection of these surgical details. Taking these limitations together, our findings need to be validated in multicenter, prospective studies with longer follow-up and standardized cosmetic assessment.

Conclusions

For relapsing GLM or when conservative treatments are inefficient or when patients show poor compliance with drug use, extended mass resection and breast defect reconstruction with an ICAP flap appears to be a feasible and safe option for selected GLM patients requiring resection. This approach may help fill tissue defects, maintain breast appearance, and improve patient-reported cosmetic satisfaction. The lower recurrence observed in the flap reconstruction group should be interpreted cautiously because of the retrospective design, potential selection bias, limited sample size, and short follow-up.

Acknowledgments

The authors thank Dr. Qi Qian and Dr. Jian-bo Dai for providing technical assistance.

Footnote

Reporting Checklist: The authors have completed the STROCSS reporting checklist. Available at https://gs.amegroups.com/article/view/10.21037/gs-2026-0168/rc

Data Sharing Statement: Available at https://gs.amegroups.com/article/view/10.21037/gs-2026-0168/dss

Peer Review File: Available at https://gs.amegroups.com/article/view/10.21037/gs-2026-0168/prf

Funding: This work was supported by grants from the Bethune Medical Foundation (No. RXAJZZL-09), the Wu Jieping Medical Foundation (320.6750.2025-21-23), the Top Talent of Changzhou “14th Five-Year Plan” High-Level Health Talents Training Project (No. 2022CZBJ065), the Changzhou Medical Center (No. CMCB202401), the Jiangsu Provincial Health Commission General Project (No. MQ2024036), the Changzhou Health Commission Scientific Research Project (No. QN202532), and the Research Fund Project for Science and Technology Development of Nanjing Medical University (No. NMUB20240044).

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://gs.amegroups.com/article/view/10.21037/gs-2026-0168/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The present study was approved by the ethics committee of Changzhou No. 2 People’s Hospital, the Third Affiliated Hospital of Nanjing Medical University (No. KY204-01). The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. Written informed consent was obtained from all patients.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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