Survival in Carcinoma of Unknown Primary to Neck Nodes Treated with Neck Dissection and Radiotherapy

Dear Sir, Carcinoma of unknown primary (CUP) represents a heterogeneous group of metastatic tumors where, even after a complete diagnostic workup the site of origin of the tumor is not detected. The diagnosis of CUP should be made after complete clinical history, physical examination, routine laboratory tests, imaging, and a careful review of the histology, and sometimes radio-metabolic techniques are also used. CUP accounts for 3-5% of all cancers.[1] The unique biology of these group of cancers remains to be fully understood. However, Stella et al. have postulated two groups for the origin of CUP.[2] The first suggests that CUP are a heterogeneous group of site specific tumors, which share the properties of the small primary from which it derives and the second regards CUP as a distinct entity with a specific genetic asset. The survival of patients with the CUP to the liver, lungs, bones, and other sites is poor. The median survival of patients with the CUP to the liver are as low as 2 months and in, CUP to the lungs, bone, and skin the median survival is 3 months.[3] The proportion of cases of CUP to the regional lymph nodes of head and neck is high in this part of the country, which accounts for 59.7% of all CUPs.[4] In this analysis, we have tried to see the survival of patients with secondary neck node (SNN) in CUP who were treated by comprehensive neck dissection (CND) of all the neck node levels followed by bilateral neck field prophylactic irradiation with external beam radiotherapy (EBRT) of 50 Gy/25 fractions without any concurrent or adjuvant chemotherapy.