Cercival lymph node metastasis of squamous cell carcinoma of an unknown primary (SCCUP): a single institutional review

Background

Squamous cell carcinoma of unknown primary (SCCUP) represents 1% to 4% of all head and neck malignancies. Five-year survival rates of 30% to 50% are reported with radical neck surgery, high-dose radiotherapy (RT) and combination modalities.

Methods

A retrospective analysis from chart review of all consecutive non metastatic SCCUP patients (pts) diagnosed and treated at our Institution between January 2009 and December 2014 was performed. Primary aim: to characterize the clinical, demographic and treatment data. Secondary aim: to evaluate overall survival (OS) and event-free survival (EFS) at 3 and 5-years using the Kaplan-Meier method and the related prognostic factors by Cox's multivariate proportional risk.

Results

From a total of 80 pts, 66 (82%) were males and 14 (18%) were females with a median age of 62 years (range 41-84). Alcohol and tobacco abuse was found in 69 and 76% of pts, respectively. Diagnostic evaluation consisting of PET-CT, cervical and thorax CT-scan, ENT examination and laryngoscopy, endoscopy and bronchoscopy were completed in 33 (41%) of pts. Distribution of pts by N status was N1 –5 pts, N2a – 7 pts, N2b – 31 pts, N2c - 3pts and N3 -34 pts. Level neck node IV/V involvement was seen in 56% pts. Extracapsular spread was found in 54 (67%) pts and G3 in 32 (40%) pts. Upfront neck dissection (ND) with biopsy of base of tongue and hypopharynx and bilateral amigdalectomy were performed in 51 pts (64%), and in 42 of those pts was followed by adjuvant treatment (RT in 17, chemoradiation (CRT) in 25). Two pts received definitive CRT, 10 isolated RT and 9 induction chemotherapy followed by CRT. Eight pts were treated with best supportive care. Seven cervical and 16 systemic (lung in 11 pts) recurrences were documented. In the multivariate analysis, ND significantly affected survival (non-surgery group hazard ratio 5.7 IC95% 2.93-11.2), p 

Conclusions

Despite the N-stage being higher than expected, our survival data were similar to the published literature. The only prognostic factor for survival in our pts was upfront neck dissection. Other prognostic factors were not statistically significant probably due to the small sample.

Clinical trial identification

Legal entity responsible for the study

Instituto Português de Oncologia de Lisboa Francisco Gentil EPE

Funding

Instituto Português de Oncologia de Lisboa Francisco Gentil EPE

Disclosure

All authors have declared no conflicts of interest.