F-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in a Case of Subcutaneous T-cell Lymphoma Presenting as Breast Mass and Panniculitis-Like Features: A Rare Entity

A 53-year-old female patient with on and off fever and swelling in the right breast for 2 months was referred to our department for fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT). Ultrasonography of the right breast depicted a lesion in lower medial quadrant. Excisional biopsy on the right breast was showing infiltration and rimming of the adipocyte cells by many atypical lymphoid admixed with few histiocytes and plasma cells. The atypical cells are medium-sized, have high n/c ratio, prominent nucleoli at places, and scant amount of cytoplasm. On immunohistochemistry, these cells are positive for CD 3 and negative for CD 4, CD 8, CD 30, and CD 20. FDG PET/CT of the patient was planned which revealed an ill-defined FDG avid (SUV max-4.6) soft-tissue density lesion in inner quadrant of the right breast with relative sparing of the nipple-areola complex and multiple areas of cutaneous and subcutaneous soft-tissue thickening and also soft-tissue thickening in the right breast parenchyma [Figures 1 and 2]. The patient underwent three cycles of Cyclophosphamide, Hydroxydaunorubicin, Etoposide: Oncovin, Prednisolone (CHEOP) and underwent PET/CT. PET/CT revealed decrease in the number, size, and avidity of previously seen soft-tissue lesion suggestive of partial metabolic response (Deauville score II). After, this patient underwent three more cycles of chemotherapy (CHEOP). Postchemotherapy PET/CT was suggestive of complete metabolic response (Deauville score). T-cell lymphoma (TCL) is invariably FDG avid, allowing FDG PET/CT to be used for pretreatment staging and restaging.

Close

Figure 1

(a) Maximum intensity projection image of the whole body of baseline positron emission tomography/computed tomography, revealing multiple fluorodeoxyglucose avid subcutaneous and cutaneous soft-tissue thickening, soft-tissue thickening in the right breast parenchyma with axillary and pelvic lymphadenopathy. (b) Fused coronal positron emission tomography/computed tomography show similar changes. (c and d) Interim and end of treatment positron emission tomography/computed tomography shows partial and complete metabolic response, respectively

Export to PPT

Close

Figure 2

(a-f) Fused axial images of breast lesion, axillary, and pelvic lymph node in the baseline and end of treatment positron emission tomography/computed tomography, respectively

Export to PPT

Subcutaneous panniculitis-like TCL (SPTCL) is a rare subtype of cutaneous TCL. It was first described by Gonzalez et al. in 1991.[1] The disease was recognized by the World Health Organization and the International Lymphoma Study Group in 1994 as a distinct entity in the recent classification of lymphomas.[2] SPTCL is divided into two major subgroups (αβ-STCL and γδ-STCL), depending on the T-cell receptor expression on the malignant T-cells. γδ-STCL is often associated with a more aggressive course and poor prognosis.[3] It presents as multiple indurated, poorly circumscribed, firm, violaceous cutaneous plaques, and nodules mimicking lobular panniculitis. Sometimes it may lead to aggressive hemophagocytic syndrome infrequently.[4] Involvement of lymph nodes or other visceral organs is rarely reported. omentum may be involved.[4567]

The role of PET/CT in SPTCL is still evolving, attributable to the rarity and heterogenicity of disease presentation. Imaging findings may simulate various inflammatory and malignant pathologies.[67] The involvement of breast parenchyma in SPTCL is a rare finding, and only a few case reports are found in the literature.[46] Imaging features addressed in the previous studies of breast lymphoma are generally nonspecific and inadequate to guide clinical practice.[8] It is of the utmost importance SPTCL breast mass does not require surgery like carcinoma. We illustrate a rare case of SPTCL presenting as a breast mass. FDG PET/CT helped in pretherapy staging and response evaluation in this case.