Cloquet's node trumps imaging modalities in the prediction of pelvic nodal involvement in patients with lower limb melanomas in Asian patients with palpable groin nodes

Abstract Patients with clinically palpable lymph node metastases to the groin are treated with groin dissection to control local disease and stage the malignancy. However, the extent of nodal dissection required to optimize survival rate is controversial. Aim To evaluate the approach to the extent of nodal dissection in advanced lower limb melanomas with clinically palpable inguinal nodes; to review survival outcomes based on the extent of nodal dissection and nodal disease. Materials and methods A prospectively maintained database of 12 patients with lower limb melanoma was analyzed. Cloquet's node was assessed based on the frozen section result which guided the decision to proceed to iliac–obturator dissection. The correlation of the results of the Cloquet's nodes and radiological imaging to the final histological outcome of groin nodal dissection were compared. Results The positive predictive value (PPV) of radiological imaging in identifying pelvic nodal disease was 60%. PPV of a positive or indeterminate frozen section result of Cloquet's node was 71.4%. Notably, all patients with a positive frozen section result for the Cloquet's node had positive pelvic nodal disease. Median DFS for all patients is 26 months (range 3–68 months) and the median OS for all patients is 28.5 months (range 5–68 months). Median DFS for node negative patients was 28 months (range 24–68 months). Median DFS for node positive patients was 20 months (range 3–36 months). Conclusion Cloquet's node was shown to be superior to radiological imaging and should be preferentially used to decide on the extent of nodal dissection.