Necrobiotic palisading granulomas associated with breast carcinoma

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.

Adult Hepatocellular Carcinoma Coexisting with Extramedullary Hematopoiesis

Extramedullary hematopoiesis (EMH) in adults usually occurs in the liver, spleen, and lymph nodes when bone marrow hematopoiesis fails. EMH has also been recognized in benign or malignant hepatic tumors, such as hepatoblastoma, hepatocellular adenoma, and vascular tumors. However, it is rarely encountered in hepatocellular carcinoma (HCC) in elderly adults, and the molecular mechanism of EMH in hepatic tumors remains unclear. We present a case of a 74-year-old man without any hematopoietic disorders and hepatitis viral infection who underwent hepatic resection for HCC. Histological examination revealed a well-differentiated HCC with trilineage hematopoiesis in the tumor and non-neoplastic liver. The coexistence of HCC and EMH in adult patients with no hematopoietic disorders is very rare and must be distinguished from poorly differentiated or dedifferentiated HCC and hepatoblastoma.

Is Mycobacterium tuberculosis carcinogenic to humans?

We highlight the ability of the tuberculosis (TB) causing bacterial pathogen, Mycobacterium tuberculosis (Mtb), to induce key characteristics that are associated with established IARC classified Group 1 and Group 2A carcinogenic agents. There is sufficient evidence from epidemiological case-control, cohort and meta-analysis studies of increased lung cancer (LC) risk in pre-existing/active/old TB cases. Similar to carcinogens and other pathogenic infectious agents, exposure to aerosol-containing Mtb sprays in mice produce malignant transformation of cells that result in squamous cell carcinoma. Convincing, mechanistic data show several characteristics shared between TB and LC which include chronic inflammation, genomic instability and replicative immortality, just to name a few cancer hallmarks. These hallmarks of cancer may serve as precursors to malignant transformation. Together, these findings form the basis of our postulate that Mtb is a complete human pulmonary carcinogen. We also discuss how Mtb may act as both an initiating agent and promoter of tumor growth. Forthcoming experimental studies will not only serve as proof-of-concept but will also pivot our understanding of how to manage/treat TB cases as well as offer solutions to clinical conundrums of TB lesions masquerading as tumors. Clinical validation of our concept may also help pave the way for next generation personalized medicine for the management of pulmonary TB/cancer particularly for cases that are not responding well to conventional chemotherapy or TB drugs.

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.

Granulomatous reaction in a patient with lung cancer: should we treat it?

In TB endemic regions, granulomatous inflammation in the samples from a tumour in the lung or in the draining lymph nodes will not be sufficient to diagnose TB as granulomas can also arise as a reaction to tumour cells http://ow.ly/tOTm30kSFAY.

Granulomatous Lymphangitis Masquerading as Relapsed Hodgkin Disease on FDG PET/CT

A 38-year-old woman with Hodgkin lymphoma was referred for staging fludeoxyglucose (18F) positron emission tomography/computed tomography (FDG PET/CT) that showed widespread intensely FDG-avid disease in multiple nodal stations above the diaphragm and spleen and extranodal involvement in the lungs and vertebral bodies. She underwent chemotherapy and radiotherapy. Progress FDG PET/CT 5 months later showed significant metabolic and anatomic response. Repeat FDG PET/CT 1 month later was highly suspicious of recurrent disseminated FDG-avid lymphoma in multiple nodal stations above and below the diaphragm, spleen, multiple bones, and lungs. Subsequent bone marrow biopsy showed sarcoid-like granulomatous inflammation with no evidence of lymphoma. The patient was clinically well and no active treatment was instituted. Subsequent FDG PET/CT 2 months later showed complete resolution of metabolic activity.

Cystic Neutrophilic Granulomatous Mastitis: Association With Gram-Positive Bacilli and Corynebacterium

OBJECTIVES

To determine whether cystic neutrophilic granulomatous mastitis (CNGM) can be associated with Gram-positive bacilli and Corynebacterium

METHODS

We reviewed our experience with 35 granulomatous mastitis patients over a 10-year period, including histologic pattern, Gram stain and other microbiologic data, clinical presentation, treatment and outcome.

RESULTS

Biopsies from 19 patients demonstrated CNGM, while 16 patients had other patterns of granulomatous mastitis. Gram-positive organisms were seen within microcystic spaces in 16/19 CNGM, but 0/16 non-CNGM patients (P = .000). Culture or molecular studies demonstrated Corynebacterium species in three, all CNGM. Patients with CNGM were more likely to be younger, of Hispanic ethnicity, and born outside of the United States. Granulomatous mastitis resolved after a protracted course with widely variable treatment (antibiotics, surgery, steroids).

CONCLUSIONS

Our data further support CNGM as an infectious disease; further study of Corynebacterium-directed therapy in CNGM is needed.

Idiopathic granulomatous lobular mastitis

Idiopathic granulomatous lobular mastitis (IGLM) is a rare breast condition with prominent skin findings. It is typically seen in young parous women. Painful breast masses, draining sinuses, scarring, and breast atrophy are the main clinical manifestations. IGLM can resemble a variety of other inflammatory and neoplastic processes of the breast. It is thought to result from obstruction and rupture of breast lobules. Extravasated breast secretions then induce an inflammatory reaction. Corynebacteria have also been implicated in the pathogenesis. Treatment is surgical, but systemic corticosteroids, methotrexate, and antibiotics also play a role.

Pure erythropoiesis in clear cell renal cell carcinoma

Extramedullary hematopoiesis (EMH) is a phenomenon in which benign immature hematopoietic cells are found in sites other than the bone marrow. Although usually associated with an underlying hematologic abnormality such as myelofibrosis, it can be found in some physiologic states or occasionally within solid tumors. In most instances, foci of EMH contain elements of all cell lineages. Presented here is the second reported case of EMH occurring in a low-grade clear cell renal cell carcinoma in a patient without evidence of hematologic disease. As previously, it manifested as pure erythropoiesis as confirmed by morphology and immunohistochemistry. It is possible that this finding is related to erythropoietin secretion by the tumor and not hematologic malignancy.