Archives of Breast Cancer
Volume:9 Issue: 3, Jul 2022

Imaging has an established role in the diagnosis and management of idiopathic granulomatous mastitis (IGM). The main purpose of this article is to explain an imaging-based diagnostic approach for IGM and describe the imaging findings of the disease.

The PubMed database was searched to find the articles published in English from January 2004 to December 2021 using the terms "idiopathic granulomatous mastitis", "imaging", and “radiology.” The search yielded 60 articles initially, of which 17 papers mainly concentrating on the imaging of IGM were assessed.

Ultrasound and mammography are the two commonly used modalities for evaluating IGM patients. Focal asymmetry and irregular high-density mass are the most common mammographic findings. Irregular hypoechoic mass with tubular extensions is a frequent ultrasound finding. Magnetic resonance imaging (MRI) can be used as a complementary modality, but it does not usually change the disease management. The most important differential diagnosis of IGM include breast cancer, infectious mastitis, and tuberculous mastitis. There is currently no agreedupon schedule for the imaging follow-up of IGM patients.

The commonly used imaging modalities for evaluating IGM include ultrasound with or without mammography. There is currently no consensus for the imaging follow-up of these patients. Copyright © 2022. This is an open-access article distributed under the terms of the Creative Commons A

Idiopathic granulomatous mastitis (IGM) is a challenging exclusion diagnosis for breast lesions, manifested as benign, chronic inflammation of the breast tissue. Although some evidence suggest that IGM cases are not uniformly distributed worldwide, few investigations have specifically addressed this topic. This study aims to examine the distribution of IGM cases among countries and races/ethnicities based on reported cases.

A review of studies with a report of at least one IGM patient published from 2011 to 2020 inclusive was conducted. The search was performed in MEDLINE, and citations were filtered in two stages by title/abstract and full text. Those cases with a positive growth of pathogens, male granulomatous mastitis and review articles were excluded.

Among 365 retrieved publications, 218 were finally included based on the inclusion and exclusion criteria, comprising 7161 patients from 34 different countries. Turkey, the United States, and China were the countries where the most publications (including case reports) originated. Considering the number of patients within papers, Turkey, Iran, and China were the pioneers.

Based on the published literature, some populations seem to be more prone to IGM. Further investigations may reveal the genetic and environmental factors associated with this disease in different geographic areas

Idiopathic granulomatous mastitis (IGM) is a rare benign inflammatory breast condition, mostly affecting women of reproductive age within a few years of pregnancy. Due to diverse clinical and radiologic features, IGM can mimic a vast spectrum of breast conditions. Therefore, histological findings are one of the most essential bases of diagnosis.

A literature search was performed to review the characteristics of IGM with an emphasis on histopathological features in English sources from 2010 to 2022. The key words used for PubMed database search were “breast”, “granulomatous mastitis”, “histopathology”, and “pathology.”

In total, 192 articles were retrieved, from which 38 most relevant manuscripts were selected for this review article.

The diagnosis of IGM depends on clinical, radiologic, and pathologic findings. Palpable mass is the most frequent complaint. An irregular hypoechoic mass with varying degrees of posterior phenomena is the most common sonographic finding. Histologically, IGM is characterized by a non-caseating lobulocentric granulomatous inflammation; composed of tight aggregates of epithelioid histiocytes with or without multinucleated giant cells. At times, the presence of cystic empty vacuoles lined by neutrophils is noted that is commonly associated with cystic neutrophilic granulomatous mastitis (CNGM), a variant of IGM. Atypical findings for IGM includes: The presence of atypia and/or malignancy, caseous necrosis, marked eosinophilic infiltration, absence of granulomatous inflammation, etc.

The use of oral corticosteroids to treat idiopathic granulomatous mastitis (IGM) has been a point of controversy for a long time. In addition, a wide diversity of combinations with other therapies have been reported so far. This study aims to review the usage of oral corticosteroids and their combinations in the published literature.

PubMed and Scopus were searched using the key word “granulomatous mastitis.” Citations were filtered in two stages, considering the titles/abstracts and full texts. Papers reporting the treatment of IGM with corticosteroids with/without other treatments were included.

Fifty-eight citations were included in this study, 31 of which had at least a group of patients treated only with systemic corticosteroids. Combination therapy of systemic steroids with immunosuppressants, surgical interventions, and antibiotics were used in 6, 12, and 13 studies, respectively.

Considering the inconsistency of studies in reporting the severity of the disease, administered treatments, outcome of treatment, side effects, and follow-up, our study failed to provide solid evidence for using corticosteroids as the first step in the management of idiopathic granulomatous mastitis. There is still a need for further studies emphasizing the homogenization of such reports. In this regard, preparing a questionnaire to help homogenize future reports on IGM is highly recommended.

Idiopathic granulomatous mastitis (IGM) is a rare relapsing benign, chronic inflammatory breast disease characterized by infiltration of inflammatory cells including multinucleated giant cells. Recently, it has been suggested that infection with Corynebacterium species (spp.) may be involved in the onset of the disease. Therefore, the aim of this article is to summarize the previous IGM reports related to Corynebacterium spp.

I used the terms "granulomatous mastitis Corynebacterium" in PubMed and "granulomatous mastitis Corynebacterium" with Japanese in Google Scholar, which resulted in 63 English articles and 71 Japanese articles. I read all the abstracts and summarized the recent articles with Corynebacterium in the title.

In 16 English articles and 4 Japanese ones, the most common Corynebacterium spp. was Corynebacterium kroppenstedtii, followed by Corynebacterium tuberculostearium.

Corynebacterium infection is widely detected with IGM. In addition to bacterial culture, real-time polymerase chain reaction and formalin-fixed, paraffinembedded biopsy specimens’ analysis can be used to detect Corynebacterium spp.

Idiopathic granulomatous mastitis (IGM) is a rare inflammatory disease of the breast with unknown etiology. Clinico-radiologic findings can mimic breast cancer. Further pathologic evaluation to rule out malignancy is mandatory. Recognizing the severity of the disease is crucial to choosing the most effective therapeutic modality. The aim of this study is to evaluate clinical and radio-pathologic features of IGM, and the treatment outcome in a large series of IGM patients in Iran.

The retrospective charts of 243 patients suspicious of IGM, between December 2007 and September 2017 were reviewed. Patients with confirmed diagnosis of IGM were classified into four grades of severity. Demographic information, clinical and radio-pathologic findings, severity and treatment outcomes were collected.

Overall, 224 patients were confirmed to have IGM. Breast mass and erythema were the most common clinical findings. Mammographic findings mimicked malignancy in 34%. Lobulo-centric non-caseating granulomas were the most common pathologic finding. Also, 61.5% of the patients had mild to moderate symptoms and 49.5% of them recovered completely by observation. In addition, 53 (25.9%) patients had severe symptoms and 30.8% of them were resistant to treatment.

IGM is a diagnostic challenge. Its diagnosis is based on exclusion and a close cooperation between the clinician, the radiologist and the pathologist. Mild to moderate cases can be managed conservatively; however, severe cases may need further aggressive medical or surgical treatments.

Idiopathic Granulomatous Mastitis (IGM) is a chronic inflammatory disease of the breast. Recent studies have shown an increase in its prevalence especially in developing countries. A standard for the treatment of the disease that has not been established yet. The aim of this cross-sectional study was to review the clinical characteristics and the result of treatment at Motamed Cancer Institute (MCI).

This retrospective study was conducted on 383 women who referred to Motamed Cancer Research Institute with confirmed diagnosis of IGM from March 2015 to February 2018. The demographic and clinical characteristics and the result of treatment options were extracted from the patients’ medical records. The data was analyzed using SPSS, version 22.

Among 383 pathologically proven patients with a mean age of 35.6 ±7.593 years, 97% had the history of pregnancy and 95.2% had breastfeeding. In response to the prescribed treatments, among 241 patients with available follow-up, the most commonly used treatment was Corticosteroids (Cs) + Methotrexate (Mtx) (70.1%), where the highest complete remission was in the group receiving Cs (100%) and Mtx (97%), respectively, and the highest partial remission belonged to Cs + Mtx at 21.3%. The shortest time to complete remission was seen in Mtx group with the mean duration of 5.83 months and the highest recurrence rate was seen in the group receiving Cs alone (16.7%).

According to the results of this study, among the prescribed treatments, the highest rate of complete remission with the lowest duration and recurrence rate belonged to Methotrexate regimen. Corticosteroids were associated with a high rate of complete remission and a high rate of recurrence. Implementing clinical trials regarding the best treatment options for IGM is recommended.

Idiopathic granulomatous mastitis (IGM) is one of the uncommon benign relapsing diseases of the breast and the imaging features of IGM can be indistinguishable from invasive or inflammatory breast carcinoma. Therefore, the assessment of the ultrasound features could be diagnostically helpful.

This retrospective research involved a total of 26 patients who had a final pathologic diagnosis of IGM and who underwent high-resolution ultrasound (US) and color Doppler evaluation.

Overall, 26 patients met the inclusion criteria. The age range of the patients was between 24 and 52 years old with an average of 34.81. About half of the patients (53.8%) reported pain as a presenting symptom and the most common physical finding was a palpable mass in 53.8% of the cases. Ultrasonography revealed the most common mass shape to be oval and irregular both with a frequency of 47.1%. Mass margins were mostly indistinct (70.6%) while angular and circumscribed margins were also seen. Heterogeneous echogenicity was observed in 71.4%, increased echogenicity of perilesional fat in 84.6%, posterior acoustic enhancement in 57.7%, peripheral vascularity in 30.8%, and subcutaneous collections in 19% of the patients., Internal vascularity was seen in 7% of the cases.

In the US of IGM, increased echogenicity of subcutaneous and perilesional fat were a common ultrasound feature (84.6%) while perilesional fat edema has not been mentioned in previous studies. In this study, other ultrasound features of IGM such as tubular extension, subcutaneous collection, indeterminate irregular masses, and collections were observed. They may contribute to the diagnosis of granulomatous mastitis in a proper clinical setting.

Lobular carcinoma in situ (LCIS) is a type of lobular neoplasia within the terminal duct lobular unit, involving more than half of acini. It is mostly diagnosed incidentally and although it is not a malignant lesion, it has an association with malignancy in the future. Idiopathic granulomatous mastitis (IGM) is a benign granulomatous disease with few simultaneous reports of malignant lesions in the literature. In this case report, we present a case with LCIS and IGM in a single breast.

A 35-year-old female presented to the breast clinic with complaints of pain and a palpable mass in the right breast. The past medical history, habitual history, drug history, and family history of cancer were negative. Physical examinations showed a palpable mass in the right breast without nipple discharge and retraction and lymphadenopathy and the left breast was intact. Breast imaging showed a right UOQ mass. A core needle biopsy was performed showing LCIS and IGM on the rightside with a positive cytoplasmic reaction for P120 catenin. E-cadherin was negative in LCIS. P63 and CK5/6 immunostainings revealed the presence of myoepithelial cells around ductal and glandular structures. The patient developed erythema nodosum at the time of diagnosis. She was put on prednisolone 50 mg per day and NSAID, and after improvement was maintained on 25 mg daily prednisolone for about 7 months, combined with 3 months of hydroxychloroquine 200 mg twice a day. At the 12-month follow-up, both breasts were completely normal in the physical examination without any mass or skin changes and the right breast mass decreased in size.

Radiologic findings of IGM can be suggestive of other possible causes and silent etiologies like the primary phase of breast cancer and LCIS should not be overlooked.

Idiopathic granulomatous mastitis (IGM) is a rare benign disease involving breast parenchyma mostly in the periareolar region. Childbearing women with a recent history of pregnancy and lactation are more at risk of IGM. The common locations of IGM are retro areolar or periareolar of the breast, but involvement of the axillary region in nonpregnant woman has never been reported elsewhere.

A 36-year-old female with a history of two times of pregnancy and lactation 8 months prior to presentation, referred with pain and swelling in the right axillary area. The past medical history and habitual history were negative and she did not use oral contraceptives or other medications. Local physical examination showed normal breasts with bilateral accessory breasts. A tender mass with the size of 4x6cm was palpable in the right axillary region accompanied by erythema and a few secretory fistulas without lymphadenopathy. Cell blood count, fasting blood glucose, HbA1C, and serum prolactin were normal. Ultra-sonography (US) demonstrated a soft tissue swelling, edema, and a decreased echogenicity area in the right axillary region compatible with IGM, which was further confirmed by biopsy. The patient was prescribed for on prednisolone 50mg per day and the condition did not improved for two months. To exclude other possible etiologies due to the atypical location, the patient underwent a second US and core-needle biopsy which confirmed the diagnosis of the axillary IGM. Prednisolone was tapered off and a non-steroidal anti-inflammatory drug (NSAID) started. All the symptoms improved in a month and fully resolved in 3 months.

IGM is not fully known yet, the presentation and the location can be variable. Considering IGM as a probable diagnosis in inflammatory presentation in the axillary region in patients with accessory breasts is suggested.