“Sign of groove” in Hodgkin’s lymphoma
A 56-year-old man presented with a 2-year history of an asymptomatic left inguinal swelling, along with generalized pruritus and weight loss of 10 kg over the last 6 months. Local examination showed inguinal swellings both above and below the left inguinal ligament, forming the ‘sign of groove’ [Figure 1]. Hematological investigations were unremarkable, except for anemia (Hb 10.6g/dL). A contrast-enhanced computed tomography scan revealed enlarged left inguinal, left iliac, and retroperitoneal lymph nodes. Inguinal lymph node biopsy showed large atypical Reed-Sternberg-like cells with immunopositivity for CD30 and focal positivity for CD15, with a background polymorphous infiltrate. A final diagnosis of classical Hodgkin’s lymphoma was made, and the patient was referred to medical oncology for further management.
Though often regarded as pathognomonic of lymphogranuloma venereum, the ‘sign of groove’ or ‘groove sign of Greenblatt’ can be seen in other conditions as well, including Hodgkin’s and Non-Hodgkin’s lymphomas. The ‘groove’ is formed by the inguinal ligament separating the inguinal lymph nodes above and the femoral lymph nodes below.