A Review of Inflammatory Processes of the Breast with a Focus on Diagnosis in Core Biopsy Samples

Estimation of fatty acid composition in mammary adipose tissue using deep neural network with unsupervised training

PURPOSE

To develop a deep learning-based method for robust and rapid estimation of the fatty acid composition (FAC) in mammary adipose tissue.

METHODS

A physics-based unsupervised deep learning network for estimation of fatty acid composition-network (FAC-Net) is proposed to estimate the number of double bonds and number of methylene-interrupted double bonds from multi-echo bipolar gradient-echo data, which are subsequently converted to saturated, mono-unsaturated, and poly-unsaturated fatty acids. The loss function was based on a 10 fat peak signal model. The proposed network was tested with a phantom containing eight oils with different FAC and on post-menopausal women scanned using a whole-body 3T MRI system between February 2022 and January 2024. The post-menopausal women included a control group (n = 8) with average risk for breast cancer and a cancer group (n = 7) with biopsy-proven breast cancer.

RESULTS

The FAC values of eight oils in the phantom showed strong correlations between the measured and reference values (R2 > 0.9 except chain length). The FAC values measured from scan and rescan data of the control group showed no significant difference between the two scans. The FAC measurements of the cancer group conducted before contrast and after contrast showed a significant difference in saturated fatty acid and mono-unsaturated fatty acid. The cancer group has higher saturated fatty acid than the control group, although not statistically significant.

CONCLUSION

The results in this study suggest that the proposed FAC-Net can be used to measure the FAC of mammary adipose tissue from gradient-echo MRI data of the breast.

Autoimmune Mastitis in a Patient with Behcet's Syndrome: A Case Report with Rapid Changes in Radiologic Features and Characteristic Pathologic Findings

Breast manifestations of autoimmune diseases are rare but may present as localized disease or as part of a systemic disease. The most common clinical presentations of autoimmune mastitis are palpable masses and mastalgia, but patients can also be asymptomatic. Its radiological features are nonspecific and varied; it usually appears as an irregular hypoechoic mass or ill-defined hypoechoic nonmass lesion that mimics malignancy, with or without duct ectasia on breast ultrasonography. On breast MRI, segmental or regional nonmass enhancement is observed. However, due to its nonspecific and rapid changes in its clinical and radiological features, its diagnosis is often challenging and delayed. Herein, we present a rare case of mastitis with mammary duct ectasia in a patient with Behcet's syndrome and its rapid changes in imaging features on serial radiologic studies. Furthermore, we review the literature focusing on the radiologic and histopathologic characteristics of autoimmune mastitis.

Periductal Mastitis, a Disease with Distinct Clinicopathological Features from Granulomatous Lobular Mastitis

Purpose

Periductal mastitis (PDM) is a chronic inflammatory lesion of the breast with an unknown etiology, and it is difficult for clinicians to differentiate it from granulomatous lobular mastitis (GLM), although they have different treatment strategies and prognosis. This study aimed to investigate the differences in their clinicopathologic features to inform treatment strategies.

Patients and Methods

Between 2011 and 2020, 121 patients diagnosed with PDM and 57 patients with GLM were retrospective analysis. Patient data were extracted on demographics, clinical presentation, pathologic characteristics, treatments and clinical response. Histopathological evaluations were performed on core needle biopsy specimens. Immunohistochemical stains using antibodies against CD3, CD4, CD8, CD20, and CD138 was performed to define immune cell infiltration.

Results

PDM patients had a higher median age compared to GLM patients (38 vs 32, p<0.001). PDM was primarily located in the areolar area, while GLM predominantly affected the peripheral quadrant of the breast (56.20% vs 75.44%, p<0.001). Histopathologically, more ductal dilatation (90.08% vs 3.51%, p<0.001), ductal wall thickening (47.93% vs 1.75%, p<0.001), and ductal rupture (44.63% vs 5.26%, p<0.001) were observed in PDM. GLM presented with significantly more granuloma (94.74% vs 10.74%, p<0.001), microabscess (68.42% vs 28.93%, p<0.001), and lipid vacuole (40.35% vs 8.26%, p<0.001) formation than PDM. Immunohistochemical analysis revealed a significant presence of CD20+ B lymphocytes in PDM and a higher prevalence of CD8+ T lymphocytes in GLM, indicating differing immune responses. Treatment outcomes varied, with PDM patients responding well to surgery and anti-mycobacterial therapy, while GLM patients showed favorable responses to steroid therapy.

Conclusion

PDM is a specific entity with a similar clinical presentation but distinct histopathological features and immune profiles to GLM. Further research is needed to elucidate the pathogenesis and optimize therapeutic approaches for these breast inflammatory conditions.

Evaluation of clinical profiles, imaging findings and antituberculosis treatment outcome in granulomatous mastitis: An Indian scenario

BACKGROUND

The management of choice for granulomatous mastitis (GM) has yet to be determined but few studies have demonstrated that anti-tubercular treatment (ATT) could be an effective alternative therapeutic option. Hence, the objective of the current study is to determine the clinical feature, radiological imaging findings, and histopathological examination results exhibited by GM and tuberculosis (TB)-proven GM as well as to evaluate the ATT clinical outcome in GM patients.

METHODS

The study was performed on 68 GM patients who were referred to the department of pulmonology by the breast clinic (from January 2018 to August 2021). Study populations were categorized into two groups GM and TB-proven GM patients and all were prescribed with standard ATT regimen and were continuously followed up. SPSS version 25 was employed for statistical assessment.

RESULTS

Our study showed that 6 patients from GM and 4 patients from the TB-proven GM group got relapsed. For patients who displayed partial remission, ATT treatment was started after assessing the side effects potential. 14.6% (n = 6) and 7.4% (n = 2) patients who initially demonstrated partial remission were also completely cured. ATT treatment curable rate was determined to be 90% (n = 37) and 81.5% (n = 22) for GM and TB-proven GM patients correspondingly. Therefore, the current study demonstrated nil significant differences between groups.

CONCLUSION

The current study warrants that ATT therapy could be an effective and better treatment of choice for GM patients irrespective of their clinical condition.

Efficacy and safety of rifampicin-based triple therapy for non-puerperal mastitis: A single-arm, open-label, prospective clinical trial

OBJECTIVES

To assess the efficacy and safety of rifampicin-based triple therapy (rifampicin, isoniazid, and ethambutol) for treating NPM.

METHODS

This single-center, single-arm, prospective clinical trial was conducted at the Second Hospital of Shandong University (Jinan, China). Patients with pathologically diagnosed granulomatous lobular mastitis and periductal mastitis received triple drugs, i.e., rifampicin (450 mg/day), isoniazid (300 mg/day), and ethambutol (15 mg/kg/day), until complete response or the investigator decided to discontinue treatment. The primary endpoint was the complete response rate (CRR) assessed by the investigator. The secondary endpoints included the overall remission rate (ORR), recurrence rate (RR), and safety.

RESULTS

A total of 218 patients were enrolled in the study between January 1, 2013 and October 31, 2020. With a median follow-up time of 48 months, the CRR and the ORR were 78.44% and 94.04%, respectively. While 13 patients (5.96%) demonstrated no response and 19 relapsed (8.72%). Adverse events (AEs) were not common. The most common AEs during treatment were liver dysfunction (1.83%), gastrointestinal reactions (1.83%), fatigue (1.83%), erythema (1.38%), and menstrual disorders (0.92%).

CONCLUSION

Rifampicin, isoniazid, and ethambutol demonstrated promising response rates with acceptable safety profiles in patients with NPM. Further confirmatory trial is warranted in the future.

TRIAL REGISTRATION

The study was approved by the Ethics Committee of the Second Hospital of Shandong University and retrospectively registered at the China Clinical Trial Registration Center (registration number: ChiCTR2100049591).

Granulomatous mastitis: A diagnostic challenge-3 year single institutional experience

BACKGROUND

Granulomatous mastitis (GM) is often clinico-radiologically misdiagnosed as breast malignancy. Tuberculosis, foreign body reactions, fungal and parastic infections, and autoimmune diseases can cause GM. The present study aimed to assess the spectrum of GM on fine-needle aspiration biopsy (FNAB) smears along with its histopathological and clinico-radiological findings.

MATERIALS AND METHODS

It was a retrospective study which included all cases of GM diagnosed on FNAB over a period of 3 years. The histopathological diagnosis was retrieved, wherever possible. All the FNA smears and histopathological sections were reviewed for the presence of epithelioid granulomas, necrosis, epithelioid histiocytes, inflammatory cells including plasma cells, neutrophils, eosinophils, multinucleated giant cells, and epithelial component and associated atypia, if any. The inflammatory cells and multinucleated giant cells were graded on a scale of 0 to 3+ in every case.

RESULTS

Among the 22 cases evaluated, the most common inflammatory infiltrate was lymphocyte followed by neutrophils and eosinophils. Caseous necrosis was appreciated in 7 (31.8%) cases, out of which 5 (22.7%) were diagnosed as tubercular mastitis on FNA smears. Ziehl Neelson stain was done in all FNAB smears and AFB was positive in 7 (31.8%) cases. Histopathological correlation was available for 14 cases (63.6%). The most common diagnosis on histopathology was idiopathic GM having lobulo-centric granulomatous inflammation, epithelioid histiocytes, neutrophils, and lymphocytes.

CONCLUSION

FNAB is a reliable and minimally invasive tool to diagnose tubercular mastitis, idiopathic GM and also ruling out clinicoradiological suspicion of malignancy. Careful examination of cytological smears can prevent an unnecessary biopsy in granulomatous lesions of breast.

Inflammatory Lesions of the Breast

CONTEXT.—

Inflammatory lesions of the breast are rare but not infrequently pose problems both clinically and morphologically, particularly on needle core biopsies. These lesions range from acute inflammatory conditions to chronic lymphoplasmacytic and lymphohistiocytic to granulomatous inflammatory diseases.

OBJECTIVE.—

To provide a comprehensive overview of inflammatory lesions of the breast, with etiopathogenesis and clinical, radiologic, and pathologic features as well as differential diagnostic considerations, clinical management, and prognosis.

DATA SOURCES.—

The existing literature in the English language, including original research articles and review articles describing inflammatory lesions of the breast.

CONCLUSIONS.—

Inflammatory lesions of the breast are characterized by a wide variety of clinical, radiologic, and morphologic features. The histopathologic differential diagnosis often includes a neoplastic process requiring ancillary studies and correlation with clinical and radiologic findings. Although most specimens display nonspecific findings precluding a definitive pathologic diagnosis, pathologists have a unique opportunity to play a crucial role in identifying key histologic features suggestive of certain entities, such as cystic neutrophilic granulomatous mastitis, immunoglobulin (Ig) G4 mastitis, or squamous metaplasia of lactiferous ducts, in the right clinical and radiologic context, and thereby guiding optimal and timely clinical management. The information presented herein will be helpful to practicing anatomic pathologists and pathology trainees in becoming more familiar with specific morphologic features and overcoming differential diagnostic challenges related to pathology reporting of inflammatory lesions of the breast.

Nano Uncaria gambir as Chemopreventive Agent Against Breast Cancer

BACKGROUND

Breast cancer is one of the main causes of death in women. Uncaria gambir is an Indonesian herbal plant that can be used as an anti-cancer. However, herbal medicines have low bioavailability, which affects their bioactivity. Nanoencapsulation can increase bioavailability and stability of bioactive compounds in herbal medicines.

PURPOSE

This recent finding tried to unravel anti-cancer and chemopreventive of U. gambir nano-encapsulated by Na-alginate.

STUDY DESIGN

U. gambir bioactive compounds were isolated and characterized using UV-Vis spectrometer, FTIR, NMR and HR-MS. U. gambir extract was nanoencapsulated using Na-alginate. Anti-cancer effect was assessed by MTT assay towards T47D cell. Meanwhile, a chemopreventive analysis was carried out in breast cancer mice-induced benzo[α]pyrene. The healthy mice were divided into 8 groups comprising control and treatment.

RESULTS

Elucidation of U. gambir ethyl acetate extract confirmed high catechin content, 89.34% (w/w). Successful nanoencapsulation of U. gambir (G-NPs) was indicated. The particle size of G-NPs was 78.40 ± 12.25 nm. Loading efficiency (LE) and loading amount (LA) of G-NPs were 97.56 ± 0.04% and 32.52 ± 0.01%, respectively. G-NPs had an EC50 value of 10.39 ± 3.50 µg/mL, which was more toxic than the EC50 value of extract towards the T47D cell line. Administration of 200 mg/kg BW G-NPs to mice induced by benzo[α]pyrene exhibited SOD and GSH levels of 13.69 ng/mL and 455.6 ng/mL. In addition, the lowest TNF-α level was 27.96 ng/mL. A dose of 100 mg/kg BW G-NPs could best increase CAT levels by 7.18 ng/mL. There was no damage or histological abnormalities found in histological analysis of the breast tissue in the group given 200 mg/kg BW G-NPs.

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.

Increased breast cancer mortality due to treatment delay and needle biopsy type: a retrospective analysis of SEER-medicare

BACKGROUND

Substantial evidence indicates that delay of first treatment after diagnosis is associated with poorer survival outcomes in breast cancer. Accordingly, the Commission on Cancer introduced a quality measure for receipt of therapeutic surgery within 60 days of diagnostic biopsy for stage I-III breast cancer patients in the non-neoadjuvant setting. It is unknown, however, what may contribute to mortality associated with treatment delay. Therefore, we investigated whether biopsy type moderates the effect of the mortality risk posed by treatment delay.

METHODS

Retrospective analysis of 31,306 women with stage I-III breast cancer diagnosed between 2003 and 2013 selected from the SEER-Medicare database was performed to determine whether needle biopsy type [core needle biopsy (CNB) or vacuum-assisted biopsy (VAB)] impacts time to treatment (TTT)-associated survival outcomes. Multivariable Fine-Gray competing risk survival models, adjusted for inverse propensity score weights, were used to determine the association between biopsy type, TTT, and breast cancer-specific mortality (BCSM).

RESULTS

TTT ≥ 60 days was associated with 45% higher risk of BCSM (sHR = 1.45, 95% CI 1.24-1.69) compared to those with TTT < 60 days in stage I-III cases. Independent of TTT, CNB was associated with 28% higher risk of BCSM compared to VAB in stage II-III cases (sHR = 1.28, 95% CI 1.11-1.36), translating to a 2.7% and 4.0% absolute difference in BCSM at 5 and 10 years, respectively. However, in stage I cases, the BCSM risk was not associated with type of biopsy.

CONCLUSIONS

Our results suggest that treatment delay ≥ 60 days is independently associated with poorer survival outcomes in breast cancer patients. In stage II-III, CNB is associated with higher BCSM than VAB. However, type of biopsy does not underlie TTT-associated breast cancer mortality risk.

Exocrine gland structure-function relationships

Fluid secretion by exocrine glandular organs is essential to the survival of mammals. Each glandular unit within the body is uniquely organized to carry out its own specific functions, with failure to establish these specialized structures resulting in impaired organ function. Here, we review glandular organs in terms of shared and divergent architecture. We first describe the structural organization of the diverse glandular secretory units (the end-pieces) and their fluid transporting systems (the ducts) within the mammalian system, focusing on how tissue architecture corresponds to functional output. We then highlight how defects in development of end-piece and ductal architecture impacts secretory function. Finally, we discuss how knowledge of exocrine gland structure-function relationships can be applied to the development of new diagnostics, regenerative approaches and tissue regeneration.

Palpable Lumps after Mastectomy: Radiologic-Pathologic Review of Benign and Malignant Masses

Patients who have undergone mastectomy, with or without reconstruction, are not universally screened with mammography or US. Therefore, clinical breast examination by the physician and patient-detected palpable abnormalities are crucial for detecting breast cancer or recurrence. Diagnostic US is the first-line modality for evaluation of postmastectomy palpable masses, with occasional adjunct use of diagnostic mammography for confirming certain benign masses. In the setting of a negative initial imaging evaluation with continued clinical concern, diagnostic MRI may aid in improving sensitivity. Knowledge of the typical multimodality imaging appearances and locations of malignant palpable abnormalities-such as invasive carcinoma recurrence, cancer in residual breast tissue, radiation-induced sarcoma, and metastatic disease-is crucial in diagnosis and treatment of these entities. In addition, familiarity with the range of benign palpable postmastectomy processes-including fat necrosis, fat graft, seroma, granuloma, neuroma, fibrosis, and infection-may help avoid unnecessary biopsies and reassure patients. The authors review common and rare benign and malignant palpable masses in mastectomy patients, describe multimodality diagnostic imaging evaluation of each entity, review radiologic and pathologic correlation, and acquaint the radiologist with management when these findings are encountered. ^©RSNA, 2021.

Mammary duct ectasia in adult females; risk factors for the disease, a case control study

Introduction

Mammary duct ectasia is a common clinical condition characterized by abnormal dilatation of the central milk ducts with chronic inflammation and fibrosis, it may affect one or both breasts. Patients may be completely asymptomatic or have mastalgia or nipple discharge which is usually from multiple ducts. It mostly affects females and is very rare in males.

Patients and methods

This is a case control study which included 236 females grouped into two equal groups, the first group were patients with duct ectasia compared and the other one apparently healthy females and both groups were compared regarding different characteristics.

Results

Most patients were young with a mean age of 35 years, a most of them were overweight (42.4%) and obese (33.1%). Most were menstruating (86.4%) with regular cycles (79.7%). Most patients had breast pain (67.8%), tenderness (54.2%), and no nodularity (98.3%). About 47.5% had nipple discharge mostly from multiple ducts (43.2%), 52.5% had no discharge. There was a significant correlation between the development of duct ectasia and each of marital status, lactational status, coffee consumption, pain, nodularity, and breast tenderness (P values 0.026, 0.016, 0.034, 0.000, 0.000, and 0.000).

Conclusion

Duct ectasia is a very common complaint in females, it is commoner in overweight and obese females, married females and those with history of lactation. Coffee consumption may be a cause. The regularity of the menstruation has no correlation with its development. The presence of mastalgia, tenderness, and nodularity are highly suggestive for the disease.

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The breast is a dynamic structure that undergo various stages of development.

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Mammary duct ectasia is a common clinical condition.

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It may affect single breast or both breasts.

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It is common in obese females, married females and those with history of lactation.

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Patients have mastalgia, breast tenderness, and nodularity.

Precision pathology as applied to breast core needle biopsy evaluation: implications for management

With the shift to de-escalation of therapy for some breast cancers and fewer surgical excisions for high-risk lesions identified on breast imaging studies at one end of the spectrum, and the greater use of neoadjuvant systemic therapy at the other end, pathologists are ever more critical in guiding management decisions for women with breast disease following core needle biopsy. One important consequence of this shift in management paradigms is the elimination of the opportunity for a "second-look" with the excision specimen to confirm or refine the diagnosis rendered on core needle biopsy. Thus, not only is there the imperative for accuracy and precision of core needle biopsy diagnoses, increasingly it is the only opportunity for that diagnosis.

A case report of TB versus idiopathic granulomatous mastitis with erythema nodosum, reactive arthritis, cough, and headache

Tuberculous mastitis (TBM) is relatively rare disease with an incidence ranging between 0.1 and 4%. Most of the cases are culture negative and often mistaken with chronic benign idiopathic granulomatous mastitis (IGM). It is very crucial to distinguish culture negative TBM from other causes of mastitis as the treatment differs tremendously. We describe here in a young woman originally from India and residing in Qatar; a non endemic area of tuberculosis; for more then fifteen years. She presented with 2 months history of right breast mass, followed by low grade fever, dry cough, headache, erythema nodosum, arthritis, and arthralgia. In view of the origin of the patient, positive family history for tuberculosis and positive quantiferon, the patient was started empirically on anti-tuberculous treatment (ATT). One week later she developed paradoxical reaction to ATT. This case illustrates unusual and rare manifestations of primary TBM and highlights the importance of differentiating and treating culture negative TBM from IGM.

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.

Factors associated with treatment duration and recurrence rate of complicated mastitis

BACKGROUND

The incidence of mastitis has increased, and this disease can lead to long antibiotic courses and complications. Here, we aimed to identify the factors associated with antibiotic duration and recurrence of complicated mastitis.

MATERIALS AND METHODS

This retrospective cohort study was conducted in a tertiary hospital in Taiwan. All hospitalized patients diagnosed with mastitis (ICD-9 code 611.0) from Jan. 1, 2012, to Dec. 31, 2016, were enrolled. Patient characteristics and clinical data were obtained from the medical charts. Recurrence was defined as mastitis within the first year after the discontinuation of antibiotics for at least 7 days.

RESULTS

In total, 214 females with a median age of 37 years old (IQR 33-45) were enrolled. A total of 148 patients (69.2%) underwent debridement, and 122 (57.0%) underwent biopsy. Histopathological examinations revealed granulation tissue in 44.6% (62/139) of the patients. Positive cultures were obtained in 65.9% (141/214) of the patients. Coagulase-negative staphylococci (64/141, 45.4%) was the most common pathogen, followed by Corynebacterium species (42/141, 29.8%). The median hospitalization length and antibiotic course were 7 (IQR 4-13) and 37 days (IQR 22-77), respectively. Three patients died of breast cancer during treatment. The recurrence rate was 18.5% (39/211). Younger age, corynebacterial infection, and pregnancy were associated with longer treatment durations (P < 0.001, 0.003, <0.001). Corynebacterial infection was associated with a 2.16-fold (95% CI: 1.11-4.20) increase in recurrence after adjusting for age.

CONCLUSION

Corynebacterial infection is associated with longer treatment courses and an increased recurrence rate of complicated mastitis. Therefore, specific treatments should be considered.

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.

Sonographic features of inflammatory conditions of the breast

Inflammatory conditions of the breast can be a diagnostic challenge, and ultrasound is a proven valuable tool in this setting. In acute infective conditions, ultrasound is often a superior tool to mammography due to the impracticality of applying compression to the breast and the increased parenchymal density of these often younger patients. Although infective processes comprise the majority of inflammatory conditions in the breast, not infrequently other various disease processes can masquerade as infections. In particular, inflammatory breast cancer can be easily misdiagnosed as an infective process and sonography can play an important role in expediting the correct diagnosis. Furthermore, aspiration, drainage and biopsy are frequently required in managing breast inflammation and breast disease generally, and ultrasound is the most practical imaging modality facilitating such interventions. This article provides a review of the ultrasound characteristics of some of the more frequently encountered inflammatory disorders of the breast which span a spectrum of acute to chronic conditions. The various conditions in this report are described in terms of their specific sonographic imaging features as well as pathogenesis, common clinical presentations, and aspects of management are outlined where appropriate.

Imaging features of granulomatous mastitis in 36 patients with new sonographic signs

PURPOSE

Idiopathic granulomatous mastitis is a rare relapsing benign inflammatory breast disease with unknown etiology. Its clinical features and imaging signs may mimic inflammatory breast cancer or some other inflammatory breast disease. This may interfere with correct and timely diagnosis and thus impose an additional burden on the costs of diagnosis and therapy, as well as patient anxiety. We aimed to characterize the imaging findings of this disease and introduce two new imaging signs.

MATERIALS AND METHODS

This prospective study examined 36 patients with imaging and a clinical diagnosis of mastitis granulomatosis who were untreated and then confirmed by pathology. Demographic information, clinical data, imaging findings, and signs were recorded.

RESULTS

The age range of the patients was 22-60 years with an average of 36 years. Most of the patients (78%) were at reproductive age. None of the patients had a family history of granulomatous mastitis. Most patients with granulomatous mastitis (89%) lived in regions with low socioeconomic status. For most patients, sonography indicated a heterogeneous hypoechoic mass with irregular shape and ill-defined margin (26 cases; 72.2%). Focal asymmetry (36%) and obscured mass (36%) were the most common mammographic findings. Two signs of duct ectasia containing secretion and high-flow pseudocyst appearance were described.

CONCLUSION

Mammographic and ultrasound findings can highly suggest a diagnosis of granulomatous mastitis in an appropriate clinical context.

Idiopathic Granulomatous Mastitis Presenting as a Breast Pseudotumor: Case Reports with Review of the Literature

Idiopathic granulomatous mastitis is a rare benign inflammatory breast disease that affects women of childbearing age with a history of breastfeeding. It usually presents as an enlarging breast mass that can greatly mimic breast cancer. Moreover, it does not have a specific radiographic finding, so the only way to reach a definitive diagnosis is by core biopsy and histology. Furthermore, a consensus regarding the best treatment modality has not been reached yet. In this report, we describe the cases of two patients who suffered from this disease, and to our knowledge, such a report is the first of its kind to address this topic in this region. Therefore, because of its uncommon nature and obscure presentation, we hereby report two cases of idiopathic granulomatous mastitis. The clinical presentation, treatment, and pathological findings are described, and a literature review on idiopathic granulomatous mastitis will be reported.

Coryneform Bacteria in Granulomatous Lobular Mastitis: Morphological Diagnosis in Breast Biopsies

Granulomatous lobular mastitis is a rare disease whose origin is still unknown and shows an increase in its frequency. Morphological, microbiological, and molecular biology studies have linked this disease to lipophilic and fastidious corynebacteria, suggesting its possible infectious etiology. This series describes and reviews in detail the distinctive morphological characteristics of the bacteria present in the granulomas of this disease, the usefulness of histochemical techniques for their identification, and our proposal for a tissue quantification score for the bacteria. The MacCallum-Goodpasture method of Gram's stain turned out to be the gold standard for examination, but we also highlight the efficiency of hematoxylin and eosin stain when it is exhaustively examined as well as the Grocott stain to evaluate the bacterial pleomorphism method, which is often underutilized.

Corynebacterium kroppenstedtii in granulomatous mastitis: Analysis of formalin-fixed, paraffin-embedded biopsy specimens by immunostaining using low-specificity bacterial antisera and real-time polymerase chain reaction

Granulomatous mastitis (GM) is a rare inflammatory disease of the post-lactation breast, clinically mimicking breast cancer. GM is microscopically characterized by formation of epithelioid granulomas and abscess (suppurative granulomas) with lipid droplet-centered inflammation. Corynebacterium kroppenstedtii (Ck) is known as a causative bacterium of GM, and identification of Ck infection within the lesion should thus be essential for confirming the diagnosis. In the present study, we analyzed formalin-fixed, paraffin-embedded (FFPE) biopsy specimens of a total of 18 GM lesions with immunostaining and real-time PCR for Ck genome. Widely cross-reactive rabbit antisera against Bacillus Calmette-Guerin (BCG), Bacillus cereus, Treponema pallidum and Escherichia coli were chosen. With real-time PCR, Ck genome was demonstrated in 7 of 18 GM lesions. Immunohistochemically, the low-specificity antisera reacted with the cytoplasm of phagocytes and/or granuloma-engulfed lipid droplets in 12 of 18 GM lesions. Antigenic positivity was observed in the following order: BCG > B. cereus > T. pallidum > E. coli. Real-time PCR using DNA extracted from FFPE sections was useful but not consistent for identifying the Ck genome in GM, while immunostaining using cross-reactive antisera against four kinds of bacteria was not Ck-specific but was applicable to visualizing bacterial infection within the GM lesions.

Idiopathic Granulomatous Mastitis: Manifestations at Multimodality Imaging and Pitfalls

Idiopathic granulomatous mastitis (IGM) is a rare benign inflammatory breast entity characterized by lobulocentric granulomas. IGM has a persistent or recurrent disease course and affects parous premenopausal women with a history of lactation. It has also been associated with hyperprolactinemia. The most common clinical sign is a palpable tender mass. However, the nonspecific manifestations and varied demographic features of this condition, as well as the other similar-appearing and superimposed breast entities, pose substantial diagnostic challenges. Entities with similar manifestations include inflammatory breast cancer (IBC), infective mastitis, foreign body injection granulomas, mammary duct ectasia, diabetic fibrous mastopathy, and systemic granulomatous processes. The strategy for imaging IGM depends on patient age, clinical manifestations, and risk factors. Targeted ultrasonography, mammography, and less commonly, magnetic resonance imaging have proven to be useful for imaging evaluation. Core-needle biopsy, with or without fine-needle aspiration for cytopathologic examination, and culture analysis are usually required to exclude IBC and other benign inflammatory breast processes. Patients with IGM have an excellent prognosis when they are appropriately treated with oral steroids or second-line immunosuppressive and prolactin-lowering medications. However, surgical excision may be an option for patients in whom medication therapy is unsuccessful. Imaging surveillance can be offered to patients with incidentally encountered IGM or mild symptoms. Clinical suspicion for this rare disease and the breast imager's prompt diagnosis can lead to an improved patient outcome. The purpose of this article is to review the imaging manifestations of IGM in a multimodality case-based format and to describe relevant clinical and imaging-based differential diagnoses. The associated pitfalls, epidemiologic and histopathologic factors, clinical manifestations, natural course, and management of IGM also are discussed. ©RSNA, 2018.

Idiopathic Granulomatous Mastitis: Cytologic and Histologic Study of 65 Egyptian Patients

BACKGROUND

The etiology of idiopathic granulomatous mastitis (IGM) is unknown, and it is commonly misdiagnosed clinically and/or radiologically as breast cancer. The role of fine-needle aspiration cytology (FNAC) in its diagnosis is still a matter of debate. The aim of the current study is to assess the value of FNAC in the diagnosis of IGM, and to search for the presence of bacteria in IGM with cystic vacuoles, which was described recently by a few authors.

MATERIALS AND METHODS

Retrospective study of cytologic smears and histologic tissue sections of 65 Egyptian IGM cases was done along with microbiologic testing. A comparison of the frequency of IGM in Egypt to that of other populations was also made.

RESULTS

IGM has typical FNA features which can easily exclude malignancy. Histologically, cystic vacuoles were encountered in 35 out of 65 cases (53.9%), with only 6 (17.14%) of these cases showing Gram-positive bacilli (GPB). The frequency of IGM in Egypt is comparable to those in other Middle Eastern countries but much higher than in Western countries.

CONCLUSION

IGM is a common breast disease in Egypt. FNAC in IGM has a high diagnostic accuracy. This study supports the few recent studies that have detected GPB in IGM with cystic vacuoles. Thus, bacteriologic examination in such cases may affect the treatment strategy.

Inflammatory breast disease: A pictorial essay with radiological-pathological correlation

Inflammatory conditions of the breast are an important group of diseases that can mimic breast carcinoma on clinical and radiological grounds. This pictorial essay presents the radiological and pathological features of some of these entities.

Granulomatous lobular mastitis

Granulomatous lobular mastitis is an unusual breast benign inflammatory disorder with unknown aetiology. It is generally emerged with the clinical symptoms of breast mass, abscess, inflammation and mammary duct fistula. The diagnosis is made by histopathology with a chronic non-necrotizing granulomatous inflammation in lobules of the breast tissue as the microscopic feature. Therapy of granulomatous lobular mastitis consists of surgical, medication treatment or combination of both, but now researches suggest that observational management is an acceptable treatment.