Role of Bacteriological Agents in Idiopathic Granulomatous Mastitis: Real or Not?

Immune pathogenesis of idiopathic granulomatous mastitis: from etiology toward therapeutic approaches

Idiopathic granulomatous mastitis (IGM) is a noncancerous, chronic inflammatory disorder of breast with unknown causes, posing significant challenges to the quality of life due to its high refractoriness and local aggressiveness. The typical symptoms of this disease involve skin redness, a firm and tender breast mass and mastalgia; others may include swelling, fistula, abscess (often without fever), nipple retraction, and peau d'orange appearance. IGM often mimics breast abscesses or malignancies, particularly inflammatory breast cancer, and is characterized by absent standardized treatment options, inconsistent patient response and unknown mechanism. Definite diagnosis of this disease relies on core needle biopsy and histopathological examination. The prevailing etiological theory suggests that IGM is an autoimmune disease, as some patients respond well to steroid treatment. Additionally, the presence of concurrent erythema nodosum or other autoimmune conditions supports the autoimmune nature of the disease. Based on current knowledge, this review aims to elucidate the autoimmune-favored features of IGM and explore its potential etiologies. Furthermore, we discuss the immune-mediated pathogenesis of IGM using existing research and propose immunotherapeutic strategies for managing this condition.

Combining intralesional steroid injection with oral steroids in patients with idiopathic granulomatous mastitis

Idiopathic granulomatous mastitis (IGM) is a chronic inflammatory breast disease. Currently, there is no international standard for steroid use in IGM, particularly for intralesional steroid injections. This study aimed to determine whether patients with IGM who received oral steroids could benefit from intralesional steroid injection. We analyzed 62 patients with IGM whose main clinical presentation was mastitis masses and who received preoperative steroid therapy. Group A (n = 34) received combined steroid treatment: oral steroids (starting dose, 0.25 mg/kg/d; tapered off) and intralesional steroid injection (20 mg per session). Group B (n = 28) received oral steroids only (starting dose, 0.5 mg/kg/d; tapered off). Both groups underwent lumpectomy at the end of steroid treatment. We analyzed the preoperative treatment time, preoperative mass maximum diameter reduction rate, side effects, postoperative satisfaction, and rate of IGM recurrence. The mean age of the 62 participants was 33.6 ± 2.3 (range, 26-46) years, and all had unilateral disease. We found that oral steroids combined with intralesional steroid injection yielded better therapeutic effects than did oral steroids alone. The median maximum diameter reduction of the breast mass was 52.06% in group A and 30.00% in group B (P = .002). Moreover, the use of intralesional steroids reduced the duration of oral steroid use; the median durations of preoperative steroid therapy were 4 and 7 weeks in groups A and B, respectively (P < .001). Group A patients were more satisfied (P = .035) with the postoperative results, including postoperative appearance and function. No statistically significant between-group differences were noted regarding side effects and recurrence rates. Preoperative administration of oral steroids combined with intralesional steroid injection yielded better therapeutic effects than did oral steroids alone and may be an effective future treatment for IGM.

Fibroblast growth factor 2 reduces endoplasmic reticulum stress and apoptosis in in-vitro Non-Alcoholic Fatty Liver Disease model

PURPOSE

Non-Alcoholic fatty liver disease is characterized by the accumulation of excess fat in the liver, chronic inflammation, and cell death, ranging from simple steatosis to fibrosis, and finally leads to cirrhosis and hepatocellular carcinoma. The effect of Fibroblast growth factor 2 on apoptosis and ER stress inhibition has been investigated in many studies. In this study, we aimed to investigate the effect of FGF2 on the NAFLD in-vitro model in the HepG2 cell line.

METHODS

The in-vitro NAFLD model was first induced on the HepG2 cell line using oleic acid and palmitic acid for 24 h and evaluated by ORO staining and Real-time PCR. The cell line was then treated with various concentrations of fibroblast growth factor 2 for 24 h, total RNA was extracted and cDNA was consequently synthesized. Real-time PCR and flow cytometry was applied to evaluate gene expression and apoptosis rate, respectively.

RESULTS

It was shown that fibroblast growth factor 2 ameliorated apoptosis in the NAFLD in-vitro model by reducing the expression of genes involved in the intrinsic apoptosis pathway, including caspase 3 and 9. Moreover, endoplasmic reticulum stress was decreased following upregulating the protective ER-stress genes, including SOD1 and PPARα.

CONCLUSIONS

FGF2 significantly reduced ER stress and intrinsic apoptosis pathway. Our data suggest that FGF2 treatment could be a potential therapeutic strategy for NAFLD.

Clinical, microbiological, immunological and hormonal profiles of patients with granulomatous mastitis

Various studies on the etiology and other aspects of granulomatous mastitis (GM) have been performed; however, a lot of controversies have arisen. The present study aimed to present the clinicopathological findings and identify the sensitivity and resistance of isolated bacteria in patients with GM. In this cross-sectional study 63 female patients with a confirmed histopathological diagnosis of GM were included. A core needle biopsy was conducted for the patients to obtain a sample for histopathological examination and bacterial culture. In total, 46 types of antibiotics were used to determine the sensitivity and resistance of each isolated bacterial species. All the medical and clinical records of the patients were acquired through the completion of a questionnaire form in person or, if necessary, through the evaluation of their medical records in the database of the relevant center. The majority of the patients were in the premenopausal or perimenopausal period. GM was unilateral in 58.7% of the patients. The most common symptom was pain, followed by fever and chills. The mean ranges of the erythrocyte sedimentation rate, C-reactive protein, IL-6, IL-17, C5a, white blood count, neutrophil-to-lymphocyte ratio, and prolactin tests were significantly elevated in comparison to the normal ranges. In total, nine different bacterial species were isolated from the bacterial culture of the core biopsy samples, and 50% of the isolated bacterial species were sensitive to trimethoprim-sulfamethoxazole. Since there is no consensus on the etiology of GM, any additional studies related to this aspect expand the current understanding of this puzzling condition.

Clinicopathologic Features and Pathogens of Granulomatous Lobular Mastitis

BACKGROUND

Granulomatous lobular mastitis (GLM) is a rare, benign, and complex breast disease that can be easily misdiagnosed as breast cancer. The etiology of GLM is unclear, and optimal treatment has not been established.

METHODS

Medical records for 333 patients with GLM in recent 5 years at Longhua Hospital, Shanghai, China, were analyzed. Potential pathogens in 33 fresh tissue specimens were also analyzed using 16S rDNA sequencing technology, matrix-assisted laser desorption ionization time of flight mass spectrometry, and bacterial cultures.

RESULTS

The median age of patients was 32 years (range 22-47 years). Among 333 patients, 38.7% displayed elevated prolactin, while 23.7% displayed high interleukin-2. In the granulomatous lesion, CD3-positive T lymphocytes were significantly more than CD20-positive B lymphocytes around the vacuoles or microabscesses. Gram-positive organisms were observed in 82 cases, including in 22 cases from fresh tissue specimens. Thirty-three cases yielded associated pathogens and all displayed multiple pathogenic infections, as identified using 16S rDNA sequencing technology. Pathogenic infections were further identified as belonging to 16 main genera and 8 main pathogenic species.

CONCLUSIONS

GLM displays distinct histological and clinical features similar to those that have been previously reported in the literature. Using 16S rDNA sequencing technology, all of our cases demonstrated multiple pathogenic infections, which provided more useful information for clinical treatment.

Idiopathic granulomatous mastitis: experience at a New York hospital

INTRODUCTION

Idiopathic granulomatous mastitis (IGM) often mimics breast cancer. Presentation includes pain, palpable mass, suppuration or suspicious imaging. Widely reported in Asia and the Middle East, IGM is diagnosed after excluding specific granulomatous mastitis (SGM). Aetiology remains unknown. Lactation, prolactinaemia, ethnicity, autoimmune disease and Corynebacteria are associated. Treatment is controversial and the prevalence rising. Surgery and non-operative treatments including antibiotics, non-steroidal anti-inflammatory drugs (NSAIDs), steroids, methotrexate and observation have advocates.

METHODS

A retrospective chart review of 63 patients with IGM from 2008 to 2018 was undertaken focusing on birthplace, age, clinical presentation, wound cultures, imaging, treatments and outcomes.

RESULTS

Sixty-one of 63 patients were Hispanic; 53 were Mexican-born women aged 23-46. Clinical presentation included pain, painful mass, painless mass, suppuration and abnormal imaging. Some 31/61 ultrasound examinations and 17/33 mammograms were deemed Breast Imaging Reporting and Data System (BI-RADS) score 4 or 5. Management included antibiotics (43), incision and drainage (24), NSAIDs (29), steroids (8), lumpectomy (18) and observation (12). Some 12/20 patients with painless masses resolved with observation, 3 received NSAIDs, 2 received steroids and 3 underwent lumpectomies. Antibiotics resolved 8/43 cases, 5 needed incision and drainage, 26 received NSAIDs, 6 received steroids and 5 underwent lumpectomies. Nineteen patients had indolent disease or recurrence.

CONCLUSIONS

Excluding malignancy is critical, treatment challenging and recurrence common in IGM. A preponderance of patients were Mexican-born, similar to other reports from the USA. Over 50% of IGM cases had suspicious BI-RADS scores. Best management remains a challenge and ranges from observation to lumpectomy.

Management of granulomatous lobular mastitis: an international multidisciplinary consensus (2021 edition)

Granulomatous lobular mastitis (GLM) is a rare and chronic benign inflammatory disease of the breast. Difficulties exist in the management of GLM for many front-line surgeons and medical specialists who care for patients with inflammatory disorders of the breast. This consensus is summarized to establish evidence-based recommendations for the management of GLM. Literature was reviewed using PubMed from January 1, 1971 to July 31, 2020. Sixty-six international experienced multidisciplinary experts from 11 countries or regions were invited to review the evidence. Levels of evidence were determined using the American College of Physicians grading system, and recommendations were discussed until consensus. Experts discussed and concluded 30 recommendations on historical definitions, etiology and predisposing factors, diagnosis criteria, treatment, clinical stages, relapse and recurrence of GLM. GLM was recommended as a widely accepted definition. In addition, this consensus introduced a new clinical stages and management algorithm for GLM to provide individual treatment strategies. In conclusion, diagnosis of GLM depends on a combination of history, clinical manifestations, imaging examinations, laboratory examinations and pathology. The approach to treatment of GLM should be applied according to the different clinical stage of GLM. This evidence-based consensus would be valuable to assist front-line surgeons and medical specialists in the optimal management of GLM.

Idiopathic granulomatous mastitis: case series and clinical review

Idiopathic granulomatous mastitis is a chronic inflammatory breast disorder that typically affects young, parous women, often following lactation. Patients present with tender, erythematous breast lesions with histological evidence of non-caseating granulomata and an inflammatory cell infiltrate. An immune-mediated pathophysiology is hypothesised and an association with lipophilic Corynebacterium species is observed. Initial diagnosis is often delayed due to lack of awareness of the condition and management of refractory disease can be challenging. We present an extensive case series of patients collaboratively managed by subspecialty physicians and surgeons at a single centre in Sydney, Australia. The accompanying review expands on features of this condition and supports the utility of a multidisciplinary approach.

Caracterización clínico-patológica y manejo de pacientes con mastitis granulomatosa crónica en un centro de alta complejidad

Introducción. La mastitis granulomatosa crónica es una enfermedad inflamatoria poco frecuente y con mayor incidencia en el sexo femenino. Su sintomatología y su presentación clínica causan gran ansiedad tanto en el paciente como en el personal médico, debido a su comportamiento similar al de la patología mamaria maligna. No hay una etiología clara ni un manejo terapéutico definido. El objetivo de este estudio fue determinar las características clínico-patológicas, el tratamiento y la evolución de las pacientes con mastitis granulomatosa, durante el periodo de estudio. Métodos. Estudio retrospectivo en el que se revisaron las historias clínicas de pacientes con diagnóstico y manejo de trastorno inflamatorio de la mama no especificado (N61X), entre enero de 2010 y diciembre de 2019. Se encontraron 236 pacientes, se excluyeron 176 por no cumplir con el diagnóstico de mastitis granulomatosa crónica o por no tener un seguimiento adecuado. Se evaluaron las características sociodemográficas, clínicas y de evolución, comparando la respuesta que se obtuvo con cada tratamiento. Resultados. Se incluyeron 60 pacientes femeninas que presentaron manifestaciones variadas. El 38,3 % (n=23) recibieron manejo antibiótico, el 30 % (n=18) fue tratado con corticoides, el 8,3 % (n=5) recibió antibióticos más corticoides y se realizó manejo expectante en el 16,6 % (n=10). El 6,6 % (n=4) de los pacientes fueron llevados a cirugía. Discusión. La mejor respuesta y la menor tasa de recidiva se encontró en las pacientes que fueron sometidas a observación y en aquellas que recibieron corticoides.

What are the new findings with regard to the mysterious disease idiopathic granulomatous mastitis?

PURPOSE

To review the demographic and clinical features and the success rates of treatment approaches for idiopathic granulomatous mastitis (IGM).

METHODS

A total of 134 patients diagnosed with IGM pathologically and treated by a single breast surgeon were retrospectively analyzed.

RESULTS

The time between the occurrence of symptoms and the last delivery was < 24 months in 25 (23.1%), 24-48 months in 51 (38.1%), and > 48 months in 52 (38.8%). The difference was statistically significant (p = 0.002). Although there was no significant difference, seasonal fluctuations were noticed, with the incidence being slightly higher during late spring and summer. Bilateral disease was present in 10 (7.5%) patients. Seven patients (5.2%) had erythema nodosum. The treatment approaches were conservative in 42, surgical procedures in 48, steroid treatment in 18, and surgical procedure + steroid treatment in 24. The median recovery time with conservative approaches was lower than that with surgical procedure + steroid treatment (p < 0.0001). Recurrence developed in 10 patients (7.7%).

CONCLUSION

Clinical differences were detected among the patients with IGM, and classification of patients by severity is needed to plan the optimal treatment approach. Seasonal fluctuations suggest the possibility of an immunological disease rather than a surgical disease.

The Role of Establishing a Multidisciplinary Team for Idiopathic Granulomatous Mastitis in Improving Patient Outcomes and Spreading Awareness about Recent Disease Trends

Background

Iidiopathic granulomatous mastitis (IGM) is stereotypically described as a mysterious entity that mimics breast carcinoma imposing management challenges. In 2002, we established a multidisciplinary team to treat patients with IGM. This study aimed to evaluate the role of this team in improving patient outcomes. Also, a review of literature is provided to highlight recent disease trends. Patients and Methods. Pertinent data for 44 patients treated for IGM from 2002 to 2018 were analyzed and compared to data prior to 2002.

Results

Mean age at diagnosis was 37.9 years ± 6.4. The diagnosis of IGM was confirmed by True-cut biopsy (TCB), Frozen section (FS), and surgical biopsy in 70.5%, 25%, and 4.5% of patients, respectively. FS was used to assess the resection margins in three patients. Suspicion for malignancy was raised in one out of 39 ultrasound reports, and one out of 20 mammography reports. Wide local excision was the main treatment modality (95.5%). 19 patients (43.2%) received corticosteroids. Prior to 2002, IGM was only recognized after surgical resection with a 71% initial false impression of carcinoma. After 2002, the initial false clinical impression of carcinoma dropped to 29.5%. Recurrence rate was 31.82%. Younger age at diagnosis was significantly associated with recurrence (χ ² = 5.598; p = 0.018). Chi-square analysis showed no significant association between BMI and recurrence (χ ² = 0.776; p = 0.678).

Conclusion

The establishment of a multidisciplinary team for IGM was associated with a reduced erroneous impression of breast cancer, and a reduced false positive radiological diagnosis of breast carcinoma. FS was a useful confirmatory procedure. Our series included the first case of a diffuse papular rash as a systemic manifestation of IGM. Recent literature indicates that IGM is changing its face. IGM is being reported in all age groups, and even in males. The clinical manifestations have markedly expanded. Diagnosis by TCB has replaced blind surgical excision. More data regarding predictors of recurrence is accumulating.

Idiopathic Granulomatous Mastitis with Skin Rupture: A Retrospective Cohort Study of 200 Patients Who Underwent Surgical and Nonsurgical Treatment

BACKGROUND

Idiopathic granulomatous mastitis (IGM) can clinically and radiographically mimic an abscess or breast cancer. Although IGM is benign, it can cause the breast skin to appear "riddled with holes" and can even result in the loss of the breast. The optimal treatment has not been established.

METHODS

We retrospectively studied the medical records of 200 patients with IGM who were treated for skin rupture from June 2015 to June 2017 in our institute. The patients' treatment modalities (including surgery after steroid therapy and steroid therapy alone), outcomes, and scores of satisfaction questionnaires were analyzed. The time to healing and recurrence rate were compared with a focus on the treatment modalities to identify the most effective treatments for IGM.

RESULTS

The median follow-up time was 15.64 months (range, 12-36 months). In total, 156 patients were treated with surgery after steroid therapy and 44 were treated with steroid therapy alone. The median times to healing in the surgical and nonsurgical groups were 25 and 258 days, respectively (p = 0.003). Four of 156 (2.56%) patients developed post-excision wound complications. Eight of 156 patients (5.1%) in the surgical group and 10 of 44 (22.7%) patients in the nonsurgical group developed recurrence (p < 0.01). The scores of the satisfaction questionnaire were 36 ± 4.28 in the surgical group and 24 ± 8.62 in the nonsurgical group (p = 0.017).

CONCLUSION

IGM is a benign disease but can have serious consequences. Surgery after steroid therapy is an effective and more satisfactory treatment than steroid therapy alone.