Re-evaluating if observation continues to be the best management of idiopathic granulomatous mastitis

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.

Idiopathic Granulomatous Mastitis

Idiopathic granulomatous mastitis (IGM) is a rare, benign inflammatory disorder of the breast that is often underrecognized. The exact etiology and pathophysiology are unknown, but milk stasis is felt to play a role. Classically, this condition is noninfectious, but many cases are noted to be associated with Corynebacterium species. Most patients affected are parous women with a mean age of 35, and many have breastfed within five years of diagnosis. Patients typically present with a painful mass and symptoms of inflammation, and these features can sometimes mimic breast cancer. Biopsy is needed to make a definitive diagnosis, and noncaseating granulomas are found on core biopsy. Many patients have a waxing and waning course over a period of six months to two years. Goal of treatment is to avoid surgery given poor wound healing, high risk of recurrence, and poor cosmetic outcomes. Medical treatment is preferred and includes observation, antibiotics, steroids, and immune modulators such as methotrexate. In more recent years, topical and intralesional steroids have become the treatment of choice, with similar outcomes to oral steroids.

Factors Affecting Recurrence of Idiopathic Granulomatous Mastitis: A Systematic Review

Idiopathic granulomatous mastitis is a rare and benign disease that primarily affects young women of reproductive age. Various factors have been suggested as possible causes, including pregnancy, breastfeeding, history of taking birth control pills, hyperprolactinemia, smoking, and history of trauma. Due to unknown etiology, opinions on its treatment have varied, resulting in differing recurrence rates and side effects. Therefore, conducting a comprehensive systematic review and meta-analysis can aid in understanding the causes and recurrence of the disease, thereby assisting in the selection of effective treatment and improving the quality of life. A systematic literature review was conducted using predefined search terms to identify eligible studies related to risk factors and recurrence up to June 2022 from electronic databases. Data were extracted and subjected to meta-analysis when applicable. A total of 71 studies with 4735 patients were included. The mean age of the patients was 34.98 years, and the average mass size was 4.64 cm. About 3749 of these patients (79.17%) were Caucasian. Patients who mentioned a history of pregnancy were 92.65% with 76.57%, 22.7%, and 19.7% having a history of breastfeeding, taking contraceptive pills, and high prolactin levels, respectively. Around 5.6% of patients had previous trauma. The overall recurrence rate was 17.18%, with recurrence rates for treatments as follows: surgery (22.5%), immunosuppressive treatment (14.7%), combined treatment (14.9%), antibiotic treatment (6.74%), and observation (9.4%). Only antibiotic and expectant treatments had significant differences in recurrence rates compared to other treatments (p value = 0.023). In conclusion, factors such as Caucasian race, pregnancy and breastfeeding history, and use of contraceptive hormone are commonly associated with the disease recurrence. Treatment should be tailored based on symptom severity and patient preference, with surgery or immunosuppressive options for recurrence.

Efficacy of preoperative Shugan Sanjie decoction combined with mammotome-assisted minimally invasive surgery in the treatment of idiopathic granulomatous mastitis: A retrospective cohort study

The management of idiopathic granulomatous mastitis (IGM) poses a significant challenge because of its ambiguous etiology. This study aimed to investigate the efficacy of traditional Chinese medicine (TCM) combined with mammotome-assisted minimally invasive surgery (MAMIS) for the treatment of IGM. This retrospective cohort study included patients with IGM who underwent treatment at our hospital between January 2017 and June 2022. Patients treated with Shugan Sanjie decoction alone and preoperative Shugan Sanjie decoction combined with MAMIS were included in Groups A and B, respectively. We focused on the demographics, clinical characteristics, and outcomes of the patients in the 2 groups. A total of 124 female patients with an average age of 33.9 ± 3.6 years were included in the study. The demographic and clinical characteristics of patients in Groups A (n = 55) and B (n = 69) were similar (P > .05). However, there were significant differences between the 2 groups in terms of treatment duration, 1-year complete remission (CR), and recurrence. Group B showed shorter treatment time (11.7 ± 5.1 vs 15.3 ± 6.4 months, P = .001), higher 1-year CR (72.5% vs 45.5%, P = .002), and lower recurrence (7.2% vs 21.8%, P = .019) in comparison to Group A. Shugan Sanjie decoction promoted the shrinkage of breast lesions in patients with IGM. Combined with MAMIS, this treatment regimen shortened the treatment duration, accelerated the recovery process, and reduced the recurrence rate.

Clinical characteristics and therapeutic strategy of granulomatous mastitis accompanied by Corynebacterium kroppenstedtii: a retrospective cohort study

BACKGROUND

Increasing evidence has suggested that Corynebacterium kroppenstedtii is associated with some cases of granulomatous mastitis, mostly based on pathology or microbiology. We aimed to identify the clinical characteristics and treatment regimens for granulomatous mastitis with Corynebacterium kroppenstedtii infection. Understanding these clinical features is essential for patient care.

METHODS

We retrospectively collected data on 201 patients who were pathologically diagnosed with granulomatous mastitis and had microbiological results of either Corynebacterium kroppenstedtii or no bacterial growth and recorded and analysed their demographics, clinical characteristics, and clinical outcomes.

RESULTS

There were 107 patients in the CK group and 94 patients in the negative group. Sinus formation (x² = 13.028, p = 0.000), time to complete remission at the first treatment period (Z = -3.027, p = 0.002), diameter of breast mass at first-time medical consultancy (Z = -2.539, p = 0.011) and recurrence (x² = 4.953, p = 0.026) were statistically significant. Age (Z = -1.046, p = 0.295), laterality (x² = 4.217, p = 0.121), time to presentation since the last delivery (x² = 0.028, p = 0.868), BMI (Z = -0.947, p = 0.344), lactation time (Z = -1.378, p = 0.168), parity (x² = 1.799, p = 0.180), gravida (Z = -0.144, p = 0.885), history of lactational mastitis or abscess (x² = 0.115, p = 0.734), local trauma (x² = 0.982, p = 0.322), hyperprolactinemia (x² = 0.706, p = 0.401), erythema nodosum (x² = 0.292, p = 0.589), and nipple discharge (x² = 0.281, p = 0.596) did not demonstrate statistical significance. Regarding recurrence related to therapeutic strategy, except for surgery combined with immunosuppressants (x² = 9.110, p = 0.003), which was statistically significant, none of the other treatment regimens reached statistical significance. The recurrence rate of patients in the CK group using rifampicin in their treatment course was 22.0% (x² = 4.892, p = 0.027).

CONCLUSIONS

Granulomatous mastitis accompanied by Corynebacterium kroppenstedtii more easily forms sinuses and has a higher recurrence rate. Both of the clinical characteristics may indicate that Corynebacterium kroppenstedtii plays an important role in the development and progression of granulomatous mastitis. Lipophilic antibiotics may be essential for granulomatous mastitis with Corynebacterium kroppenstedtii infection.

Challenging Management of a Breast Mass: Case Report and Literature Review

Idiopathic granulomatous mastitis (IGM) is a rare benign pathology of inflammation in the breast that commonly affects parous women of reproductive age and men although it is extremely rare. It has an unusual predilection for Hispanic women born outside of the United States, most notably in Mexico. Recently, this entity has been described more. However, the approach to management is still very controversial, and the approaches vary widely, although surgical approaches, including excision or mastectomy, have been less favored recently as a primary approach. Here, we present a case of a young female of reproductive age who presented initially with a suspicious breast lump diagnosed initially in the breast clinic as IGM and was referred to the rheumatology clinic for management with medical therapy.

Demographic and Socioeconomic Risk Factors for Granulomatous Mastitis in the United States: A Case-Control Study

OBJECTIVE

Granulomatous mastitis (GM) is a benign breast disease that can have an extended clinical course impacting quality of life and causing breast disfigurement. Granulomatous mastitis has been studied throughout the world; however, less is known about GM patients in the United States. We aim to identify demographic and socioeconomic factors associated with GM in the United States.

METHODS

An IRB-approved retrospective case-control study was performed of 92 patients with biopsy-proven GM at two institutions in Los Angeles, California: a safety-net hospital and an academic institution. Age-matched controls were selected from patients presenting for diagnostic breast imaging. Demographic and socioeconomic characteristics were collected. Data were analyzed using univariable test for odds ratios (ORs) with 95% confidence intervals (CIs) and multivariable conditional logistic regression.

RESULTS

Patients with GM were more likely to prefer Spanish language (OR 6.20, 95% CI: 2.71%-14.18%), identify as Hispanic/Latina (OR 5.18, 95% CI: 2.38%-11.30%), and be born in Mexico (OR 3.85, 95% CI: 1.23%-12.02%). Cases were more likely to have no primary care provider (OR 3.76, 95% CI: 1.97%-7.14%) and use California Medicaid for undocumented adults (OR 3.65, 95% CI: 1.89%-7.08%). In the multivariable analysis, participants who preferred Spanish language had four times higher odds of GM versus those who preferred English language (OR 4.32, 95% CI: 1.38%-13.54%).

CONCLUSION

Patients with GM may have barriers to health care access, such as preferring Spanish language, being an undocumented immigrant, and not having a primary care provider. Given these health care disparities, further research is needed to identify risk factors, etiologies, and treatments for this subset of GM patients.

Idiopathic Granulomatous Mastitis (IGM): Clinical Features and Non-Surgical Management

Background: Idiopathic Granulomatous Mastitis (IGM) is a benign disease; it can clinically and radiologically mimic the symptoms of breast cancer. Objectives: Due to the rare and limited number of studies in Iran, this study was designed and conducted to evaluate patients' clinical characteristics and treatment management with IGM. Methods: In this cross-sectional and retrospective descriptive-analytic study, we studied the medical records of 293 patients with IGM, such as demographic information, characteristics of breast lesions, type of treatment, complications, and their outcome, which were recorded in the Cancer Research Centers of Shahid Beheshti University of Medical Sciences (SBMU) from 2010 to 2019. The patients were contacted by telephone to visit clinically or collect additional information. Data were analyzed by SPSS software version 24. Results: The mean age of patients was 39.21 (ST = 8.29) years. Breast involvement in 236 cases (80.5%) was unilateral, and in 50 cases (17.1%), the involvement was Pere pri-Areola. The most common type of treatment was conservative therapy (analgesia + drainage) (178 cases, 60.8%), which was the primary treatment in our study; 66 patients (22.5%) received antibiotic therapy + analgesia + drainage, and 41(14%) cases received corticosteroid in addition to this treatment. Totally, 132 cases (79.5%) were completely cured with the performed treatments, 17 cases (5.8%) had a recurrence of symptoms, and 14.7% of the patients were still receiving treatment. Recurrence after 1 year in patients who had a longer duration of disease (more than 12 months) was higher than in those who had a shorter period (less than 12 months) (15.3% vs. 5.1%, P = 0.004). Also, the highest recurrence rate was in the group receiving corticosteroids compared to the group receiving the usual treatment and usual treatment plus antibiotics. This relationship was statistically significant (22.0% vs. 9 % and 6.1%, respectively, P = 0.032). Complications (scar or breast skin color change) were significantly higher in patients without a pregnancy history than in patients who had pregnancy (50.0% vs. 22.8%, P = 0.030). Also, these complications were significantly higher in patients who had a longer duration of disease (more than 12 months) than in shorter periods of disease (less than 12 months) (31.4% vs. 17.3%, P = 0.005). Conclusions: The results of our study and its comparison with the results of other studies still emphasize the uncertainty of the etiology of IGM disease and its treatment, but to some extent, our study has shown that conservative treatment (drainage with analgesic drugs) is one of the best treatment options. Also, corticosteroid therapy is associated with a higher recurrence rate, but in some cases is necessary and recommended in many studies.

Corynebacterium kroppenstedtii breast abscesses in context, a retrospective cohort study

Corynebacterium kroppenstedtii breast abscesses and granulomatous mastitis have gained increased recognition in the 20 years since their association was first described. No studies to date have described this organism in the context of all breast abscess pathogens. We retrospectively reviewed 160 community-acquired breast abscess samples from 135 patients in a 3 year period, describing the organisms isolated along with risk factors, site of infection and outcomes. We compared patient subgroups with acute and chronic abscesses, the latter defined as having a requirement for repeat aspiration more than 1 month apart. The prevalence of C. kroppenstedtii breast abscesses was 8 % in all patients (11/135), rising to 32 % in chronic abscesses (10/31), but only 1 % in acute abscesses (1/104; P<0.01). Only 10 % (1/10) of patients with C. kroppenstedtii chronic abscesses were smokers, whereas 75 % of patients (15/20) with non-C. kroppenstedtii chronic abscesses were smokers (P=0.01). C. kroppenstedtii should be considered in recurrent and prolonged infections, especially in non-smokers, and diagnostic methods altered accordingly. Identifying C. kroppenstedtii provides diagnostic clarity and alters management with recommendations for longer courses of treatment using non-beta-lactam antibiotics.

Management of Granulomatous Lobular Mastitis and Risk Factors Associated with Recurrence

BACKGROUND

Granulomatous lobular mastitis (GM), an inflammatory breast lesion with unknown etiology, is prone to recur. There is no global consensus on the optimal treatment at present. This study was conducted to show our step-by-step systemic procedure and discuss the recurrence risk factors of GM.

METHODS

The medical record database was retrospectively searched for patients with GM treated in our hospital between January 2015 and September 2021. Patients were divided into non-recurrence group (group A) and recurrence group (group B). Demographic and clinical characteristics, treatment and follow-up were collected and analyzed.

RESULTS

A total of 885 GM patients were included in our study, all of whom received step-by-step systemic management. The mean age was 33.2 ± 5.2 years. There were 760 (85.9%) patients in group A and 125 (14.1%) in group B. Univariate analysis showed that there was no statistically significant difference between the two groups in size of mass, pregnancy, hyperprolactinemia, bacterial cultures, erythema nodosum. Multivariate analysis showed that patients with purulent nipple discharge, skin lesion, bilateral disease and patients who need the combination of surgery and medication to achieve complete remission had higher risk of recurrence.

CONCLUSIONS

We built a step-by-step systemic procedure for GM, and the recurrence rate was 14.1%. Prolactin level and microbiological results are important for the management of GM. Purulent nipple discharge, skin lesion, bilateral disease and patients who need the combination of surgery and medication to achieve complete remission are associated with GM recurrence. Prolonged maintenance therapy may secure a better prognosis.

Characteristics and Management of Granulomatous Lobular Mastitis Associated with Antipsychotics-Induced Hyperprolactinemia

Background: Granulomatous lobular mastitis (GM) is a rare inflammatory breast disease. Reports focusing on GM caused by antipsychotic-induced hyperprolactinemia (HPRL) are very rare. Aim: To report a study of GM associated with antipsychotic-induced HPRL and discuss the mechanism and management. Materials and Methods: A retrospective review of patients with GM and psychiatric disorders were carried out. The clinical characteristics, management and outcome were collected and analyzed. The relationship between antipsychotics and GM was evaluated using the Naranjo Adverse Drug Reaction Probability Scale (Naranjo scale). Results: Nineteen female GM patients with psychiatric diseases, aged 21-39 years, who had received antipsychotics for 0.5-10.2 years were included. Most patients took multiple antipsychotics, and 10 (52.6%) took risperidone-containing regimens. Increased prolactin (PRL) was detected in all patients (range 35.15-200 ng/mL). The scores of Naranjo scale were 7-8, indicated the antipsychotics probably induced GM. All patients received systemic therapy, and were prescribed bromocriptine. Seven patients (36.8%) decreased the dose of antipsychotics, six (31.6%) switched antipsychotics, three (15.8%) continued the primary antipsychotics, and three (15.8%) discontinued antipsychotics. In addition, 14 patients (73.7%) received corticosteroid, 4 (21.1%) received antimycobacterials. PRL decreased to normal in 1 month. Seven patients (36.8%) received excisional surgery. After 12 months' follow-up (range 9-56 months), only three patients (15.8%) had a recurrence. Conclusion: Long-term use of antipsychotics may increase PRL levels, and lead to GM. It is vital to assess PRL level and reduce PRL to normal in patients with GM.

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.

Inflammatory diseases of the breast

Inflammatory disorders of the breast are common benign breast conditions. Lactational mastitis occurs in breastfeeding women and may be associated with breast abscess in severe cases. Non-lactational inflammatory disorders are less common and include idiopathic granulomatous mastitis, periductal mastitis, and tuberculous mastitis. While these disorders have some similarities in their presentation, each disorder requires a specific treatment regimen for resolution, and correct diagnosis is crucial for appropriate treatment. In this chapter, we will review the presentation, diagnosis, and management of each of these distinct clinical entities.

Treatment of bilateral granulomatous lobular mastitis during lactation with traditional Chinese medicine: A case report

BACKGROUND

Granulomatous lobular mastitis (GLM) is a type of benign chronic inflammatory disease that poses therapeutic challenges to healthcare providers. The diagnosis of GLM relies on tissue biopsy, and incorrect treatment may lead to delayed diagnosis, considerable aesthetic damage, and even mastectomy.

CASE SUMMARY

We report the case of a 37-year-old Chinese woman who was lactating and had GLM in both breasts. At the time of treatment, the right breast had a mass of approximately 15 cm × 11 cm, which was hard and had poor mobility. Multiple skin ulcerations and pus spills were also observed on the surface of the breast. The left breast had a mass of about 13 cm × 9 cm, which was hard and had poor mobility.

CONCLUSION

Herein, we report a case of bilateral GLM in a lactating woman that was successfully treated with traditional Chinese medicine (TCM), without the requirement for surgery or other treatments. Therefore, TCM may have advantages in the nonsurgical treatment of GLM.

Pregnancy Associated Granulomatous Mastitis: Clinical Characteristics, Management, and Outcome

Background: We have already known that idiopathic granulomatous mastitis (IGM) is a rare benign chronic inflammatory disorder that can clinically mimic breast carcinoma, especially affects parous women of childbearing age, but there is little literature to report about pregnancy associated granulomatous mastitis (PAGM). The aim of our study is to report and describe the clinical signs, managements, clinical course, and clinical outcomes after treatment of PAGM in our hospital. Methods: We retrospectively analyzed 15 pregnant patients who were diagnosed as PAGM in our hospital collected from December 2018 to December 2020 by reviewing medical records and questionnaire survey, including the patients' characteristics, clinical presentations, microbiological workups, tissue pathology, treatment modalities, outcomes, and follow-up data. Results: The mean age of these patients at diagnosis was 30.5 (range 24-35) years. All patients had one birth before, and had at least two gravida times, 6 of them (40%) had three gravida times, and only one of them had four gravida times at diagnosis. The mean weeks of gestational age were 23.7 (range 4-37) weeks. Two patients' BMI were greater than 30, which were considered obese. The mean time to presentation since last delivery was 38.4 (range 19-78) months. All patients had a history of breastfeeding; the average breastfeeding time was 12.97 months. Just 2 of them were diagnosed with lactational mastitis before. One patient smoked before, 1 patient had oral contraceptive pills before, 4 patients had breast trauma recently, 5 patients had positive bacterial culture of pyogenic fluids, 3 patients had nipple retraction, 6 patients had abnormal humoral immunity, shown as elevated C3 or C4, and 2 patients had elevated serum prolactin. All patients presented as a breast mass with pain; two of them had erythema nodosum and oligoarthritis. Nearly all patients had unilateral lesion. The mean follow-up was 11 (range 1-24) months. Thirteen patients gave birth to a healthy baby, and all babies had a healthy growth and development. Almost all patients chose observation during pregnancy. Nine patients demonstrated complete remission, five of them underwent surgery after steroids and/or antibiotics, one patient had observation alone, two chose postpartum steroids alone, and the last one chose postpartum antibiotics alone. The average time to complete remission was 11.2 (range 7-18) months. Conclusions: In general, PAGM is a much rare disorder which has onset during pregnancy, and mainly happens in the second trimester and the third trimester. PAGM patients were all parous women and generally within 5 years of their last pregnancy, also with uncertain etiology and pathogenesis. Observational therapy during pregnancy for PAGM is reliable and feasible.

Breast Imaging After Dark

Patients may present to the emergency department with breast complaints due to traumatic or nontraumatic changes in the breast. Benign and malignant breast pathologies may mimic each other both in clinical presentation and imaging appearance. A complex cystic and solid mass seen on ultrasound in a patient with a palpable mass can represent breast cancer, abscess, or hematoma. A unilateral swollen breast may result from inflammatory breast cancer, mastitis, or other benign etiologies; correlation with clinical history, physical exam, and close follow-up are required to ensure complete resolution of symptoms. Uncommon breast entities such as granulomatous mastitis and breast implant-associated anaplastic large-cell lymphoma may cause changes in the appearance of the breast that prompt a patient to seek initial evaluation in the emergency department. Imaging evaluation of the breast in the emergency department is limited, and it is important that patients with a breast complaint be referred to a dedicated breast center for complete evaluation at an appropriate time interval after their discharge from the emergency department.

Idiopathic Granulomatous Mastitis Presenting in a Patient With Hypothyroidism and Recent Hospitalization for Myxedema Coma: A Rare Case Report and Review of Literature

Idiopathic granulomatous mastitis (IGM) is a rare, benign inflammatory disorder of the breast. Clinical features may include painful breasts, erythema, subcutaneous nodules, and ulcerative lesions. It can mimic various other breast pathologies, and it is a diagnosis of exclusion after infection, malignancy, and other inflammatory conditions have been ruled out. In this article, we present a case of IGM developing in a 40-year-old female 3 months after hospitalization for myxedema coma. A contrast-enhanced magnetic resonance imaging of the breasts showed bilateral edema, and a biopsy was negative for malignancy or infection. She was started on prednisone and had noticeable improvement of ulcerations within several weeks. IGM is a rare condition that requires a multimodal treatment approach. Often recalcitrant disease is encountered and requires surgical intervention, immunosuppression, and antimicrobial therapy. The diagnosis should be entertained in patients with bilateral breast inflammation to avoid unnecessary surgical resection early on.

Treatment of Granulomatous Mastitis: Is There a Role for Antibiotics?

OBJECTIVE

To perform a retrospective review of the clinical characteristics, microbiological data, and clinical outcomes in patients with granulomatous mastitis (GM) who were treated at our institution with a unique strategy of prolonged antibiotic therapy as the primary treatment modality.

MATERIALS AND METHODS

A retrospective case series was performed on patients (n = 42) with GM seen at the breast specialty clinic of our institution between the years 2004 and 2014. Patients were primarily treated with lipophilic antibiotics, and steroids and surgery were reserved for refractory cases.

RESULTS

Bacteria were identified in 34 samples from 22/42 patients (52.3%). Diphtheroids (presumptive Corynebacterium spp.) were most commonly identified, followed by Corynebacterium spp. and Propionibacterium acnes (now Cutibacterium acnes). Antibiotics were our preferred first-line medical therapy and were used in 33/36 (91.7%) patients. The mean duration of antibiotic therapy was 7.0±4.5 months. Clarithromycin was our antibiotic of choice and was the initial antibiotic used in 15 of the 33 patients (45.5%) treated with antibiotics. Eleven patients required adjunctive therapy with prednisone. The mean duration of steroid therapy was 4.3±2.5 months. Surgery for therapeutic purposes included incision and drainage in seven patients, fine needle aspiration in eight patients, and excision of the fistulous tract in one patient. No patients had large-volume excisions. The average time from the first breast clinic visit to clinical resolution was 8.0±4.6 months.

CONCLUSION

GM may be the result of a bacterial process that induces a unique form of inflammatory response. Clinicians should consider special requests to microbiology laboratories to attempt to isolate Corynebacterium spp. in the evaluation of samples sent to the laboratory for analysis. An extended course of a lipophilic antibiotic is a largely unexplored but potentially effective treatment option with low associated morbidity. More research is needed in this area.

Oncoplastic Breast Surgery Techniques When Surgery is Essential for the Management of the Idiopatic Granulomatous Mastitis

BACKGROUND

Immunosuppressive agents are the main treatment options for idiopathic granulomatous mastitis (IGM). However, in some patients, the remaining large pouch and seroma may cause recurrence and severe deformity. Oncoplastic breast surgery (OBS) techniques can be used when surgery is required.

MATERIAL AND METHODS

In this study, surgical results of the patients histopathologically diagnosed with IGM who underwent any of the OBS techniques between 2016 and 2020 were evaluated. Patient characteristics, surgical indications, and technical details of the surgery were recorded.

RESULTS

Eighteen patients who underwent wide excision combined with the OBS technique were included in the study. Surgery was performed owning to persistent disease (n = 12), recurrence (n = 3), and patient preference (n = 3). No major complications occurred after the OBS technique. None of the patients had recurrence at the surgical site.

CONCLUSIONS

When surgery is indicated in patients with IGM, successful results can be obtained with acceptable complication rates by using the simplest and easiest applicable OBS techniques, including volume displacement technique.

Clinical characteristics and predictive factors of erythema nodosum in granulomatous lobular mastitis

BACKGROUND/OBJECTIVES

In recent years, there is a growing incidence of granulomatous lobular mastitis (GLM), but studies about the coexistence of erythema nodosum (EN) and GLM are rare. In this study, we assess the clinical characteristics and predictive factors of EN in GLM.

METHODS

A total of 303 patients diagnosed with GLM were enrolled from January 2012 to October 2018 at the second affiliated Hospital of Guangzhou University of Traditional Chinese Medicine, including 78 patients with EN. Follow-up data included: lesion site, lesion size, therapy approaches, course of GLM, course of EN, the recurrence of disease, possible causes. All patients had pathologic confirmation of GLM based on core needle biopsy (CNB) or surgical excision.

RESULT

Fever in the EN group was significantly more common compared to the non-EN group (44.87% vs 12.89%, P < 0.001). The proportion of lesion range >2 quadrants in the EN group was significantly higher than that in the non-EN group (42.31% vs 16.00%, P < 0.001). The course of the disease was longer in the EN group compared to the non-EN group (10.32 moths vs 8.74 moths, P < 0.001). Patients with EN had a trend towards a higher risk of recurrence (5.13% vs 1.33%, P = 0.055).

CONCLUSION

EN is more likely to be found in GLM patients with breast lesion range >2 quadrants. The presence of EN in GLM indicates that the condition becomes more severe and the course of GLM also becomes longer.

Granuloma after breast conserving surgery-a report of three cases

Granulomatous mastitis is a rare breast disease that is categorized as a benign tumor with chronic inflammation. Since the cause of the chronic inflammation is usually unknown, it is sometimes called idiopathic granulomatous mastitis (IGM). Although imaging modalities, such as ultrasound, magnetic resonance imaging and mammography can detect tumors, they are sometimes unable to differentiate between benign and malignant tumors. In such cases, biopsy is needed to make a correct diagnosis. We experienced three cases of IGM after breast conserving surgery in breast cancer patients in whom we needed to rule out recurrence of breast cancer. In our cases, tumorectomy was performed in two cases for pathological diagnosis, since neither biopsy nor cytology was able to reveal a conclusive pathological diagnosis. Our management of these three cases might suggest the appropriate management of granulomatous tumors after breast conserving surgery in breast cancer survivors.

Serum C-Reactive Protein and Interleukin-6 Levels as Biomarkers for Disease Severity and Clinical Outcomes in Patients with Idiopathic Granulomatous Mastitis

Idiopathic granulomatous mastitis (IGM) is a rare inflammatory breast disease mimicking breast cancer. Limited research has been conducted on the application of serum biomarkers. This study aims to investigate the association of serum biomarkers with disease severity in patients with IGM. From November 2011 to March 2020, medical records of patients with IGM were reviewed. Serum cytokine levels were measured in patients and healthy controls between July 2018 and March 2020. A total of 41 patients with histologically proven IGM were found. Serum interleukin (IL)-6 level was significantly higher in patients with IGM (n = 11) than healthy controls (n = 7). Serum IL-6 and C-reactive protein (CRP) levels were significantly higher in patients with severe disease than mild and moderate disease. Serum IL-6 (Spearman’s ρ = 0.855; p < 0.001) and CRP (Spearman’s ρ = 0.838; p = 0.001) levels were associated with time to resolution. A higher serum CRP level was associated with a longer time to resolution (B = 0.322; p < 0.001) in multiple linear regression analysis. Serum IL-6 and CRP levels can be used as biomarkers for the evaluation of disease severity in IGM. IL-6 may play a crucial role in the immunopathology of IGM.

A rheumatologic approach to granulomatous mastitis: A case series and review of the literature

AIM

Idiopathic granulomatous mastitis (IGM) is an enigmatic inflammatory breast disorder. IGM responds to immunomodulatory treatment and may be associated with systemic manifestations such as arthritis and erythema nodosum. These patients are increasingly referred to rheumatologists for management, but IGM is rarely discussed in the rheumatology literature. The objective of this report is to familiarize rheumatologists with the treatment and systemic manifestations of IGM. We report here a case series of IGM at our institution, and a literature review of IGM treated with methotrexate (MTX).

METHOD

Patients with IGM at our institution were identified and described using a retrospective chart review. A literature review of PubMed and Google Scholar identified studies of IGM patients treated with MTX.

RESULTS

We identified 28 IGM patients at our institution. Inflammatory arthritis/arthralgia were present in four patients (14%), and five patients (18%) had erythema nodosum. Patients treated with MTX had the highest rates of relapse-free remission; relapse-free remission occurred in four of the five (80%) MTX-treated patients, compared with 5 of 12 (42%) patients treated with steroids alone, and two or three (66%) patients treated with steroids and surgery. In the literature review, 116 patients treated with MTX were identified, and the rate of relapse-free remission ranged from 58% to 100%. Arthritis/arthralgia and erythema nodosum were more common at our institution than reported in the literature.

CONCLUSION

Methotrexate is a promising treatment for IGM. Arthritis/arthralgias and erythema nodosum may be under-recognized when IGM patients are managed outside rheumatology. Prospective studies are needed to characterize clinical features and optimum treatment of IGM.

Idiopathic Granulomatous Mastitis: Etiology, Clinical Manifestation, Diagnosis and Treatment

Idiopathic granulomatous mastitis (IGM) is a rare form of chronic inflammatory breast disease. Although it is a benign breast lesion, it may be sometimes difficult to distinguish from breast cancer. The cause of IGM is unknown, but may be associated with autoimmunity, abnormal hormone levels and infection. While the clinical manifestations of IGM involve various manifestations of inflammation, the diagnosis is principally established by histopathology, characterized by non-caseating granulomas and microabscess formation centered on the breast lobules. Therapeutic options for IGM range from observation to various medical treatments, such as steroids, immunosuppressants, and antibiotics, to surgical intervention, particularly if secondarily infected. Given that the controversy on etiology and treatment choices, we accomplished the present review through reviewing IGM-related literature published in 'Pubmed' and 'Web of science' databases during 1997 to 2020, aiming to provide the basis for rational clinical diagnosis and treatment.

Granulomatous mastitis, erythema nodosum and arthritis syndrome: case-based review

Granulomatous mastitis (GM) is a rare form of inflammatory breast condition associated with unilateral or bilateral breast pain, swelling and mass formation. Although the disease pathogenesis remains unknown, several reports have associated GM with manifestations such as erythema nodosum and occasionally with arthritis, suggesting that GM might have an autoimmune disease component. We aim to describe two cases of coexistence of GM, erythema nodosum, and arthritis. We also conducted a literature review to comprehensively assess and describe the characteristics of patients with GM, erythema nodosum, and arthritis, and identify effective treatment options. A literature review was conducted using PubMed and EMBASE, and 14 case reports/series were retrieved, with a total number of 29 patients. All patients are women and unilateral breast involvement was evident in the majority of patients. Nine patients (31%) presented with arthritis, 6 patients (20.7%) had a fever, and 6 patients (20.7%) developed the symptoms during pregnancy. All patients had normal chest radiograph and tissue cultures were negative. In most of the cases (n = 25, 86.2%), symptom improvement was observed with glucocorticoids and four patients (13.8%) underwent surgical treatment for the GM. Given the clinical characteristics of patients with GM, with erythema nodosum, with or without arthritis, and the positive response to glucocorticoids, we propose that the described phenotype represents an underrecognized systemic autoimmune disease that could be designated by the acronym "GMENA" (granulomatous mastitis, erythema nodosum, arthritis) syndrome. Further studies are needed to elucidate the pathogenesis of the syndrome.

Whole genome sequence of Corynebacterium kroppenstedtii isolated from a case of recurrent granulomatous mastitis

We describe the case of a 33-year-old woman with recurrent granulomatous mastitis associated with Corynebacterium kroppenstedtii. This organism has been increasingly associated with granulomatous mastitis, specifically the cystic neutrophilic histopathologic variant, although currently there is a paucity both of reported cases and genomic sequence data. We highlight the challenges in the diagnosis and treatment of this entity, in particular focusing on the various methods of microbiologic identification, including MALDI-TOF, 16 s rRNA PCR and whole-genome sequencing.

Postoperative Yanghe decoction regimen improves outcomes for idiopathic granulomatous mastitis: A retrospective cohort study

The etiology of idiopathic granulomatous mastitis (IGM), a rare inflammatory breast disease, is not understood. There is no consensus regarding the treatment of IGM. The purpose of this study was to determine the efficacy of surgery combined with traditional Chinese medicine for the treatment of IGM.We retrospectively analyzed 53 patients of IGM who were treated with surgical excision at our hospital. Group A (n = 25) included patients treated with only surgery, and Group B included patients treated with surgery combined with postoperative Yanghe decoction. The clinical data were compared between the 2 groups, including demographics, clinical characteristics, and outcomes.All patients were female with a mean age of 34.6 ± 5.9 years. There were no significant differences between the groups regarding preoperative demographics or clinical characteristics. The follow-up time was comparable between the groups (13.2 ± 10.0 vs 12.0 ± 10.2 months). Patients in Group B had shorter complete remission (CR) times than patients in Group A (76.1 ± 15.2 vs 84.0 ± 12.2 days; P < .05). The CR rate was higher in Group B than in Group A (96.4% vs 76.0%; P < .05), and the recurrence rate was lower in Group B than in Group A (0% vs 16.0%; P < .05).The postoperative Yanghe decoction regimen was associated with more rapid recovery after IGM surgery. Surgical management combined with postoperative oral Yanghe decoction treatment yielded a higher CR rate and lower recurrence rate than surgery alone. The effect of traditional Chinese medicine in IGM treatment requires further study.

Granulomatous mastitis, watch and wait is a good option

BACKGROUND

Idiopathic granulomatous mastitis (IGM) is a benign and rare chronic inflammatory disease of the breast with unknown etiology. While there is no consensus regarding its post-diagnosis management, there are different treatment alternatives.

AIMS

In this study, it was aimed to question the effectiveness of follow-up strategy without administering any treatment.

METHODS

One hundred eighteen female patients diagnosed with IGM were retrospectively evaluated. Patients with histopathologically confirmed IGM were included in the study. Medical treatment was given only to patients who did not accept the follow-up option without treatment. The protocol used in steroid therapy was 16 mg prednisolone twice daily for 2 weeks, and then the dose was gradually reduced, and the treatment was stopped after 2 months. Patients were followed up with a physical examination every 3 months. The effectiveness of the systemic corticosteroid treatment and the follow-up approach without any treatment was compared. The recurrence rates and pre-treatment and post-treatment methods of the patients were examined.

RESULTS

While 30.5% of the patients recovered with corticosteroid treatment, 42.4% recovered under observation without any treatment. The mean recovery period of the patients in these two groups was calculated as 3.9 months and 5.6 months, respectively. However, no statistically significant difference was found in terms of recovery period (p = 0.064). The recurrence rate was 11.9%.

CONCLUSION

For IGM, the "watch and wait" approach is an effective option. A chance should be given to the self-limiting nature of the disease with the addition of drainage when necessary.

Mastitis in Autoimmune Diseases: Review of the Literature, Diagnostic Pathway, and Pathophysiological Key Players

Mastitis frequently affects women of childbearing age. Of all the pathological breast conditions requiring specific management, autoimmune mastitis is in the third position after infection and breast cancer. The aim of this literature review was to make a comprehensive description of autoimmune diseases targeting the mammary gland. Four main histological patterns of autoimmune mastitis are described: (i) lymphocytic infiltrates; (ii) ductal ectasia; (iii) granulomatous mastitis; and (iv) vasculitis. Our literature search found that all types of autoimmune disease may target the mammary gland: organ-specific diseases (diabetes, thyroiditis); connective tissue diseases (such as systemic erythematosus lupus or Sjögren’s syndrome); vasculitides (granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis, giant cell arteritis, polyarteritis nodosa, Behçet’s disease); granulomatous diseases (sarcoidosis, Crohn’s disease); and IgG4-related disease. Cases of breast-specific autoimmune diseases have also been reported, including idiopathic granulomatous mastitis. These breast-limited inflammatory diseases are sometimes the first symptom of a systemic autoimmune disease. Although autoimmune mastitis is rare, it is probably underdiagnosed or misdiagnosed. Early diagnosis may allow us to detect systemic diseases at an earlier stage, which could help to initiate a prompt, appropriate therapeutic strategy. In case of suspected autoimmune mastitis, we hereby propose a diagnostic pathway and discuss the potential pathophysiological pathways leading to autoimmune breast damage.

Cystic neutrophilic granulomatous mastitis: an update

Cystic neutrophilic granulomatous mastitis (CNGM) is a rare subtype of granulomatous mastitis with a highly distinct histological pattern often associated with Corynebacterium species. CNGM is characterised by suppurative lipogranulomas that are composed of central lipid vacuoles rimmed by neutrophils and an outer cuff of epithelioid histiocytes. Some of the lipid vacuoles may contain sparse, rod-shaped, gram-positive bacilli that can be easily missed or dismissed. The surrounding mixed inflammatory infiltrate contains Langhans-type giant cells, lymphocytes and neutrophils. CNGM occurs in reproductive age women with a history of pregnancy and typically presents as a palpable mass that can be painful. CNGM has many mimickers, most significantly breast carcinoma. In many cases, CNGM has significant pathological and clinical overlap with other forms of granulomatous mastitis. Given the association with Corynebacterium species, early diagnosis of CNGM is essential in offering patients the most appropriate treatment. Prolonged antibiotic therapy specifically directed to corynebacteria is required, sometimes even beyond resolution of clinical symptoms. This comprehensive review of the existing literature on CNGM describes clinical-pathological features, microbiological findings, challenges associated with the microscopic differential diagnosis, clinical implications of this diagnosis and emerging treatment options. Morphological criteria and suggested comments to convey the degree of diagnostic certainty are also proposed for standard pathology reporting.