Sporotrichoid granuloma annulare-like dermatitis associated with systemic B-cell lymphoma.

IMPORTANCE Granuloma annulare is typically a benign, self-limited disease. Atypical presentations have been reported in association with systemic disease, including malignancy. Such patients may require additional diagnostic studies to assess for underlying malignancy. We report a patient with extensive sporotrichoid granuloma annulare-like dermatitis in association with systemic B-cell lymphoma. OBSERVATIONS An 83-year-old man with a three-year history of progressive sporotrichoid annular plaques and nodules on the arm developed ipsilateral retroauricular palpable lymphadenopathy, the latter consistent with B-cell lymphoma. Multiple skin biopsies of the plaques and nodules revealed granuloma annulare-like dermatitis. Lesions were unresponsive to intralesional and intramuscular corticosteroids, antibiotics, and antifungal agents, but rapidly improved following initiation of rituximab to treat his underlying lymphoma. CONCLUSIONS AND RELEVANCE Atypical presentations of granuloma annulare including granuloma annulare-like dermatitis warrant evaluation for systemic malignancy in a subset of patients.