Paraneoplastic granulomatous dermatitis in a patient with Hodgkin's disease: a diagnostic pitfall

The association of malignant lymphomas with non-necrotic epithelioid granulomas has been reported rarely since 1977. Hodgkin's disease-associated widespread cutaneous granuloma annulare (GA) has been reported in only eight patients. We report the second case of subcutaneous GA associated with Hodgkin's disease. A 73-year-old man with Epstein-Barr virus-associated Hodgkin's lymphoma and paraneoplastic subcutaneous GA, presented 3 months after the diagnosis of malignancy. Examination revealed a large, broad erythematous, indurated, subcutaneous plaque spanning the majority of the left lower back and flank with no associated symptoms. Initial biopsy was suggestive of morphea. Prompted by positron emission tomography (PET) findings of increased fluorodeoxyglucose (FDG) uptake, a second, deeper biopsy was performed, revealing subcutaneous palisaded granulomatous dermatitis. After complete workup, the diagnosis most strongly suggested subcutaneous GA. This case highlights the importance of deep incisional biopsies, the fluorodeoxyglucose - positron emission tomography (FDG-PET) findings in GA and the rare association of GA with Hodgkin's disease which may signal the presence of malignancy.