Cervical lymph node metastases of squamous cell carcinoma from an unknown primary: Outcomes and patterns of failure

Context: Management of cervical lymph nodes metastases of squamous cell carcinoma (SCC) from primary of unknown origin (PUO) is contentious and there is insignificant data from India on this subject.
Aims: To present experience of management of these patients treated with curative intent at a single institution.
Settings and Design: Retrospective study of patients treated between 1989-1994 in a tertiary referral cancer centre.
Materials and Methods: Eighty-nine patients were evaluated in the study period and their survival compared with patients with common sites of primary in the head and neck with comparable node stage.
Statistical analysis used: Kaplan-Meier method.
Results: The clinical stage of the neck nodes at presentation was N1 in 11%, N2a in 28.5%, N2b in 22.5%, N3 in 35% and Nx in 3.4% patients. All patients underwent surgery and 70 patients received more than 40Gy postoperative radiotherapy. Twenty-nine (32.6%) patients had relapse of which 19 (21%) were in the neck. Postoperative radiotherapy did not influence the neck relapse (p=0.72). Primary was detected in 13 patients (14.6%) on subsequent follow up. The overall five and eight-years survival was 55% and 51% respectively. The overall five-year survival was better compared to patients with known primary with comparable node stage.
Conclusions: Patients with cervical lymph nodes metastases of SCC from PUO have reasonable survival and low rate of development of subsequent primary when treated with surgery and radiotherapy. The overall survival is comparable to that of patients with known primary and hence an attempt at cure should always be made.

Keywords
Cervical metastases, head and neck, squamous cell carcinoma, unknown primary