Clinical Study Of Elective Mucosal Iradiation For Head And Neck Cancer Of Unknown Primary

ObjectiveHead and neck cancer of unknown primary(HNCUP)represent a small and heterogeneous group of patients.The optimal management is still controversial.Radiotherapy plays an important role,however,no consensus reached in term of radiation target volumes..Particular areas of controversy persist regarding whether elective mucosal irradiation should be done.Methods Clinical data of consecutive HNCUP patients treated with Intensity Modulated Radiation Therapy from 2009.01 to 2016.04 in Shanghai Ninth People’s Hospital and Fudan university Shanghai Cancer Center were retrospectively collected.The main eligibility criteria including: the diagnosis was histologically confirmed including metastases squamous cell carcinoma,poorly differentiated carcinoma,or undifferentiated carcinoma;underwent comprehensive workup;patients with metastases limited to supraclavicular lymph nodes were excluded.All patients were divided into elective mucosal irradiation(EMI)group and neck treatment(NT)group based on the irradiation volume.Survival curves were estimated with the Kaplan–Meier method using the log-rank test.SPSS 20.0 software was used for statistical analysis.Results After a median follow-up of 63 months(range 5-126 months),the 5-year overall survival(OS)of the 62-patient study population was 86.1%.The 5-year mucosal control rate(MC),neck control rate(NC),distant metastasis-free survival(DMFS)and disease-free survival(DFS)were 86.8%,89.5%,93.5%,and 72.4%,respectively.The 5-year MC was 100% and 72.0%(p=0.003)in patients treated with elective mucosal irradiation and neck treatment,The 5-year NC was 92.9% and 57.7%(p=0.002),respectively.Primary tumor emerged in 7(26.9%)in neck treatment group.Conclusion In conclusion,the present experience showed that elective mucosal irradiation helps provide the best balance between efficiency and toxicity in patients with head and neck cancer of unknown primary.Prospective study with more patients and long follow-up are needed to better answer the question of management of HNCUP.