Large B‐cell lymphoma of the leg

Abstract

A 74‐year‐old Mexican man presented with an 18‐month history of multiple, violaceous, coalescing, firm, tender nodules with an ulcer in the anterior aspect of the right leg (Fig. 1) and slightly infiltrated, ill‐defined erythematous plaques affecting the left leg and both forearms. He had not received any treatment for his condition. Past medical history was relevant for noninsulin‐dependent diabetes mellitus and hypertension without formal treatment and a history of heavy alcohol intake in his youth. A biopsy specimen of both plaque‐type lesions of the forearm and tumorous lesions of the leg showed a diffuse, nonepidermotropic mononuclear infiltrate throughout the dermis and extending to the subcutis. The infiltrate was composed of pleomorphic, atypical, large mononuclear cells (Fig. 2). Immunostaining with CD20 was positive for the atypical cells while CD3 was positive for normal appearing lymphocytes, characterized as reactive T cells. Additional laboratory and image studies ruled out extracutaneous involvement. The diagnosis of primary cutaneous large B cell lymphoma of the leg (LBCLL) was made. The patient was initiated on radiotherapy localized to the right leg with a very good initial response, nevertheless resolution was not achieved and the plaques in the rest of the limbs remained unchanged. Thus, the patient started chemotherapy with CHOP (Cyclophosphamide, Vincristine, Doxorubicin, Prednisone). He has currently finished his fourth cycle with this chemotherapy regimen. The tumorous lesions involuted leaving only residual hyperpigmentation (Fig. 3) and the plaques in the rest of the limbs disappeared, the area of the ulcer diminished considerably. There is still no evidence of extracutaneous involvement.Nodules and ulcer in the anterior aspect of the right legimageAtypical lymphocytes, with large, pleomorphic nuclei and multiple nucleoles. Positivity for CD20 antigen was demonstrated by immunohistochemical analysis (hematoxylin and eosin; X 600)imageResidual hyperpigmentation and granulation tissue after chemotherapyimage