Extra Abdominal Desmoid (Fibromatosis) of the Breast- Report of a Case Highlighting Diagnostic Difficulties and Review of Literature

Case Report

J Pathol & Microbiol. 2016; 1(2): 1010.

Extra Abdominal Desmoid (Fibromatosis) of the Breast- Report of a Case Highlighting Diagnostic Difficulties and Review of Literature

Priya S* and Lakshmikanth RM

Department of Pathology, Metropolis Healthcare limited, India

*Corresponding author: Priya S, Consultant Pathologist, Metropolis Healthcare limited, India

Received: December 01, 2016; Accepted: December 18, 2016;Published: December 21, 2016

Abstract

Fibromatosis of breast, also known as Extra Abdominal Desmoid tumour is extremely rare and poses a diagnostic challenge as it may mimic carcinoma both clinically and radio graphically. We report a case of thirty year old female, who presented with a firm mass in the right breast. The clinical and ultrasound diagnosis was suspicious of carcinoma and since the fine needle aspiration cytology was non diagnostic, an excision biopsy was performed. Routine histopathological examination showed proliferating spindle cells in long fascicles with infiltrative margins. Mitotic figures were less than two per ten high power fields. The differential diagnosis considered were collagenized or fibrous variant of myofibroblastoma, nodular fasciitis, low-grade fibrosarcoma, spindle cell metaplastic carcinoma, fibrous histiocytoma and scar from healed fat necrosis. Immunohistochemical examination revealed the spindle cells to be positive for vimentin, smooth muscle actin, beta catenin and negative for cytokeratin, S100 and desmin. Hence the diagnosis of fibromatosis was rendered, following which a completion wide excision was performed. The patient is asymptomatic without recurrence on eight months follow up. To conclude, we present this rare case and discuss its diagnostic difficulties, differential diagnosis and the role of Immunohistochemistry in evaluation.

Keywords: Extra abdominal desmoids; Fibromatosis; Breast; Immunohistochemistry

Abbreviations

CD: Cluster of Differentiation

Case Presentation

A thirty year old female presented to the surgical outpatient department with complaints of swelling in the right breast of 6 months duration. On clinical examination a 3.5X3 cm firm mass was palpable in the upper outer quadrant. Ultrasound examination showed a hypo echoic infiltrative mass and mammographic examination revealed a stellate tumour suspicious of malignancy. A Fine needle aspiration cytology performed elsewhere, was non diagnostic and hence an excision biopsy was done.

The mass was received in the histopathology laboratory in ten percent neutral buffered formalin. Grossly the mass measured 3X2.5 cm. The cut surface of the mass was gray white, homogenous and firm (Figure 1). Routine processing of the tissue was done, paraffin embedded blocks obtained and 4 micrometer thick sections were cut and hematoxylin and eosin staining was done. Microscopy showed a tumour with infiltrative borders. The spindle cells were arranged in interlacing fascicles, bundles and in focal storiform pattern admixed with abundant blood vessels and collagen bundles (Figure 2A). The cells had uniform oval to spindle nuclei with no pleomorphism. The tumour was more cellular at the periphery with few compressed ducts and had tendency to collagenization in the centre. Focal areas of hyalinization, odema, stromal lymphocytic and eosinophilic infiltrates were noted (Figure 2B). The mitotic figures were less than 1 per 10 high power fields. There were no areas of necrosis or pleomorphism. Immunohistochemistry revealed positivity for vimentin (Figure 3A) smooth muscle actin (Figure 3B) and beta catenin (Figure 5). The tumour cells were negative for S100, desmin and CD34.