The two primary types of non-puerperal mastitis (NPM) are granulomatous lobular mastitis (GLM) and plasma cell mastitis (PCM). Existing research indicates that immune inflammatory response is considered to be the core of the pathogenesis of GLM and PCM, and both innate and adaptive immune responses play an important role in the pathophysiology of PCM and GLM. However, the regulatory balance between various immune cells in these diseases is still unclear. Consequently, we present a comprehensive summary of the immune-related variables and recent advances in GLM and PCM.

Granulomatous mastitis (GM) is a rare, benign inflammatory breast disease that predominantly affects women of childbearing age and often mimics breast carcinoma. The diagnosis requires histopathological examination due to nonspecific imaging findings. Treatment includes antibiotics, corticosteroids, and surgery, but no standardized protocols exist. This autobiographical case report describes a 34-year-old woman with a tender breast lump following trauma, initially misdiagnosed as a simple abscess. Despite incision and drainage, she developed erythema nodosum, persistent fever, and arthritis, which responded to corticosteroids. Further investigation, including an ultrasound-guided biopsy and MRI, confirmed GM. Recurrent symptoms were managed with prednisolone and doxycycline, leading to significant improvement. This case report aims to highlight the diagnostic challenges associated with GM, emphasizing the necessity for a detailed histopathological examination to achieve an accurate diagnosis. It also brings attention to the significant emotional impact on patients facing a rare and complex diagnosis. By presenting this case, we aim to highlight the critical importance of a comprehensive and multidisciplinary approach to patient care in managing GM effectively.

BACKGROUND: Tuberculous mastitis (TBM), is an uncommon form of extra-pulmonary tuberculosis. Clinical and radiological overlap of tuberculous mastitis with malignancy and other granulomatous conditions, along with its paucibacillary nature, make it a diagnostic challenge. In our study, we aim to assess the radiological response of microbiologically negative granulomatous mastitis cases to anti-tuberculous treatment (ATT) in an endemic country.
METHODS: Eighty-seven cases demonstrating granulomatous lesions on breast biopsy were identified. Of these, 49 patients who were treated with ATT and had at least two serial ultrasound follow-ups were included in our study. Mammogram and ultrasound were used for initial imaging. Subsequently, ultrasound was used for serial follow-up. Mantoux skin test, acid fast staining and histological examination of tissue sample were the other investigations used.
RESULTS: Radiologically, on ultrasound, well-circumscribed hypoechoic masses were noted in 18 patients, followed by ill-defined collections with tubular extensions in 15 cases, abscesses in 8, and a focal heterogeneity in 8 patients. Following ATT, 17 patients showed radiological resolution in 4 weeks, 18 of them at 3 months, and nine of them in 6 months.
CONCLUSIONS: Excellent and prompt radiological response to ATT, indicates the need for a high degree of suspicion for tuberculous mastitis (TBM), in endemic countries, even though microbiological tests may turn out negative.

BACKGROUND: Granulomatous lobular mastitis (GLM) is a rare benign inflammatory disease of the breast and is classified under comedo mastitis in traditional Chinese medicine (TCM). The etiology of this disease is unknown, and it mainly occurs in women of childbearing age. The diagnosis depends on histopathological biopsy. At present, there is no systematic and standardized treatment plan for GLM. In the absence of evidence supporting an infectious etiology, affected patients might continue to receive multiple courses of antibiotics and unnecessary surgery.
METHODS: A 37-year-old Chinese woman with a history of coronavirus disease 2019 infection presented with swelling and pain in the left breast. She also had erythema, nodules in the lower extremities, arthritis in both knees, cough, and headache. In the early stage of GLM, the mass was not significantly reduced by conservative treatment with internal application of TCM; hence, surgical treatment was carried out. The aim of postoperative treatment was to drain the pus, eliminate the necrosed tissue, and expand the muscles; fumigation and washing using TCM was applied.
CONCLUSIONS: Combined internal and external treatment with TCM, following the principle of \"Prioritize internal treatment before ulceration and emphasize external treatment after ulceration\" was effective in our patient with GLM. The prognosis was good. We believe that TCM offered valuable therapeutic benefits in this disease.

Idiopathic granulomatous mastitis (IGM) is a benign, chronic inflammatory lesion of the breast. Immunoglobulin G4 (IgG4) associated disease is rare in the breast. In our study, we aimed to evaluate the efficacy of steroid treatment on IgG4 levels in tissue in patients diagnosed with IGM. Between 2008 and 2017, 55 patients diagnosed with IGM in our clinic were included in the study. Demographic, clinical, microbiologic and histopathologic characteristics, treatment modality and recovery time were evaluated retrospectively. Patients were divided into 3 groups according to tissue IgG4 levels: negative (Group I), infrequently and slightly positive (Group II), and highly positive (Group III). Group I patients had a complete response rate of 77.8%. In the rest of the patients (22.2%), insufficient response was detected from the beginning of the treatment. In Group II, the response rate was 91.3% and the permanent success rate after treatment was 87.0%. Although group III patients had a complete response at the beginning (95.65%), they relapsed in a short period of time (26.1%) after discontinuation of steroid treatment. At least one steroid-related side effect was observed in 47 (85.8%) patients in all groups. There is no consensus on the dose and duration of immunosuppressive treatment in IGM. In this study, responses to steroid treatment according to IgG4 concentration in pathologic breast tissue and recurrences after the end of treatment were determined. We think that high IgG4 concentration in the tissue is associated with recurrence and other immunosuppressive drugs should be added as maintenance after steroid treatment.

Granulomatous mastitis (GM) is a long-term inflammatory disease of the breast that usually occurs in women of reproductive age. Autoimmune mastitis is one of the most common pathological breast conditions necessitating tailored treatment. However, GM as a first clinical manifestation of sarcoidosis is uncommon. Simultaneous occurrence of GM, erythema nodosum (EN), and arthritis, termed \"GMENA\" syndrome, is a rare clinical entity associated with autoimmune rheumatic diseases. Herein, we report the case of a 31-year-old female patient with GMENA syndrome, who presented with a painful nodule of the left breast. Initial treatment entailed antibiotics under the presumption of a breast abscess, yielding negligible improvement. During this period, the patient developed polyarthritis and bilateral EN on the lower extremities. Histopathologic examination of the breast tissue exhibited noncaseating granulomas. The patient responded positively to prednisolone and methotrexate treatment. Literature review revealed a coherent pattern across GMENA cases. Our findings suggest that the \"GMENA\" syndrome represents a unique acute manifestation of sarcoidosis and highlight the necessity for heightened awareness, accurate diagnosis, and tailored therapeutic approaches for GMENA syndrome. Further research is warranted to elucidate its cause and optimize patient management. This case highlights the importance of identifying and effectively managing such interrelated clinical presentations.

BACKGROUND: Granulomatous mastitis (GM) is a benign, chronic, inflammatory disease lacking clear treatment guidelines. The purpose of this American Society of Breast Surgeons (ASBrS) prospective, multisite registry was to characterize the presentation of GM and identify treatment strategies associated with symptom resolution and optimal cosmesis.
METHODS: ASBrS members entered data into a registry on patient demographics, treatment, symptoms, and cosmesis over a 1-year period. Initial symptoms were graded as mild, moderate, or severe. The Chi-square test and logistic regression were used to identify factors related to symptom improvement and cosmesis.
RESULTS: Overall, 112 patients with a mean age of 36 years were included. More patients were Hispanic (49.1%) and from the Southwest (41.1%), and management included observation (4.5%), medical (70.5%), surgical (5.4%), or combination treatment (19.6%). Immunosuppression was used in 83 patients (74.1%), including 43 patients who received intralesional steroid injections. Patients with severe symptoms were more likely to undergo surgical intervention compared with those with mild or moderate symptoms (21.4% vs. 0% and 7.5%, respectively; p = 0.004). Within 1 year, 85 patients (75.9%) experienced symptom improvement and/or resolution at a median of 3 months. Receipt of immunosuppressive therapy was predictive of improvement or resolution at 1 month (odds ratio 4.22; p = 0.045). One-year physician-assessed cosmesis was excellent or good for 20/35 patients (57.1%) and was not associated with type of treatment or symptom severity.
CONCLUSIONS: Although GM can have a protracted course, the majority of patients in this registry resolved within 1 year, with good cosmetic result. Treatment with immunosuppression appears to be most beneficial, and a symptom-based algorithm may be helpful to guide treatment.

Idiopathic granulomatous mastitis (IGM), a recurrent inflammation disease of the non-lactating breast, has had an increasing clinical morbidity rate in recent years, and its complicated symptoms and unclear etiology make it challenging to treat. This rare benign inflammatory breast disease, centered on the lobules, represents the most challenging type of non-puerperal mastitis (NPM), also known as non-lactating mastitis. In this study, patients diagnosed with IGM (M, n = 23) were recruited as cases, and patients with benign control breast disease (C, n = 17) were enrolled as controls. Cytokine microarray detection measured and analyzed the differentially expressed cytokine factors between IGM and control patients. Then, we verified the mRNA and protein expression levels of the significantly changed cytokine factors using Q-RT-PCR, ELISA, western blot, and IHC experiments. The cytokine factor expression levels significantly changed compared to the control group. We observed a significant increase between IGM and control patients in cytokine factors expression, such as interleukin-1β (IL-1β), monokine induced by gamma interferon (MIG), macrophage inflammatory protein (MIP)-1α, MIP-1β, tumor necrosis factor receptor 2 (TNF RII). Then, we verified the expression of these top five dysregulated factors in both mRNA and protein levels. Our results demonstrated the cytokine map in IGM and indicated that several cytokines, especially chemokines, were associated with and significantly dysregulated in IGM tissues compared to the control group. The chemokine factors involved might be essential in developing and treating IGM. These findings would be helpful for a better understanding of IGM and offer valuable insights for devising novel diagnostic and therapeutic strategies.

OBJECTIVE: To describe the histopathological pattern of different breast lesions among tissue specimens sent to our laboratory.
METHODS: A record-based study using a retrospective review of 255 histologically diagnosed breast biopsy reports in the histopathology department of authors from December 2016 to November 2021 was conducted. The specimens were collected from core biopsy, lumpectomy, and mastectomy. All data obtained were analyzed using the Statistical Package for the Social Sciences (SPSS) version 28 (IBM SPSS Statistics, Armonk, NY). Then, the findings were presented using text, tables, and charts.
RESULTS: A total of 255 breast lesions were analyzed in this study. Most of the cases were benign (58.8%), followed by inflammatory lesions (21.6%), and malignant (19.6%). Fibroadenoma was the most prevalent benign lesion (36.7%), and most of the patients (70.9%) were in the age group of 20-39 years old. The most common inflammatory lesion was granulomatous mastitis (56.4%), and most of the cases were diagnosed in the age group of 30-39 years old. Invasive ductal carcinoma (IDC) was the most encountered histological type of carcinoma (62%). Of the malignant cases, 52% were diagnosed before the age of 50 years. Among these 50 cases, grade 2 was the most prevalent one (46%).
CONCLUSIONS: Benign breast lesions are more common than malignant breast lesions, and fibroadenoma is the most common benign subtype. Granulomatous mastitis is the most prevalent inflammatory breast lesion. About two-thirds of malignant cases are non-Arab. Invasive ductal carcinoma with no special type (NST) is the most common malignant subtype.

UNASSIGNED: Breast augmentation through the injection of polyacrylamide hydrogel (PAAG) was a popular procedure in the past, but it has since been prohibited due to various complications, including masses, migration, infection, inflammation, and even cancer. However, there were rare cases of granulomatous mastitis with pectoralis major muscle defect following PAAG injection for breast augmentation.
UNASSIGNED: A 40-year-old female patient presented with a swollen and suppurative mass in her left breast and was insensitive to antibiotics. She was admitted to our department for further treatment after 7 months with progressive local and general symptoms. Ultrasound imaging showed ill-defined heterogeneous echoes, and contrast-enhanced magnetic resonance imaging (MRI) revealed non-mass enhancement lesions in the multiregional distribution in Breast Imaging-Reporting and Data System 4A (BI-RADS 4A) with oedema in the retroglandular space and multiple enlarged lymph nodes in the ipsilateral axilla. Intraoperative observations revealed necrotic tissues, multiple abscesses, residual mucoid PAAG prosthesis diffused into the mammary glands and intramuscularly into the pectoralis muscle, and partial loss of pectoralis major muscle. Histopathological results revealed foreign-body granulomas accompanied by gel-like granular PAAG and proliferative inflammatory cells. She recovered after undergoing the characteristic surgical management in our center under general anesthesia and had no recurrence during the 2-year follow-up.
UNASSIGNED: This case revealed that PAAG injection for augmentation mammaplasty, even after the removal operation, could result in subsequent complications, including granulomatous mastitis and pectoralis major muscle damage. PAAG filler complications are difficult to treat, therefore, it is essential to establish appropriate and effective therapeutic procedures.