title: Intensity-modulated radiotherapy for cervical node squamous cell carcinoma metastases from unknown head-and-neck primary site: M. D. Anderson Cancer Center outcomes and patterns of failure.
abstract: OBJECTIVE
  Conventional therapy for cervical node squamous cell carcinoma metastases from an unknown primary can cause considerable toxicity owing to the volume of tissues to be irradiated. In the present study, hypothesizing that using intensity-modulated radiotherapy (IMRT) would provide effective treatment with minimal toxicity, we reviewed the outcomes and patterns of failure for head-and-neck unknown primary cancer at a single tertiary cancer center.
  
  
  METHODS
  We retrospectively reviewed the records of 52 patients who had undergone IMRT for an unknown primary at M.D. Anderson Cancer Center between 1998 and 2005. The patient and treatment characteristics were extracted and the survival rates calculated using the Kaplan-Meier method.
  
  
  RESULTS
  Of the 52 patients, 5 presented with Stage N1, 11 with Stage N2a, 23 with Stage N2b, 6 with Stage N2c, 4 with Stage N3, and 3 with Stage Nx disease. A total of 26 patients had undergone neck dissection, 13 before and 13 after IMRT; 14 patients had undergone excisional biopsy and presented for IMRT without evidence of disease. Finally, 14 patients had received systemic chemotherapy. All patients underwent IMRT to targets on both sides of the neck and pharyngeal axis. The median follow-up time for the surviving patients was 3.7 years. The 5-year actuarial rate of primary mucosal tumor control and regional control was 98% and 94%, respectively. Only 3 patients developed distant metastasis with locoregional control. The 5-year actuarial disease-free and overall survival rate was 88% and 89%, respectively. The most severe toxicity was Grade 3 dysphagia/esophageal stricture, experienced by 2 patients.
  
  
  CONCLUSIONS
  The results of our study have shown that IMRT can produce excellent outcomes for patients who present with cervical node squamous cell carcinoma metastases from an unknown head-and-neck primary tumor. Severe late complications were uncommon.
authors.affiliation: Department of Radiation Oncology, University of Texas M D Anderson Cancer Center, Houston, TX 77030, USA. sjfrank@mdanderson.org
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Frank
authors.forename: David I
authors.initials: DI
authors.lastname: Rosenthal
authors.forename: Janjira
authors.initials: J
authors.lastname: Petsuksiri
authors.forename: K Kian
authors.initials: KK
authors.lastname: Ang
authors.forename: William H
authors.initials: WH
authors.lastname: Morrison
authors.forename: Randal S
authors.initials: RS
authors.lastname: Weber
authors.forename: Bonnie S
authors.initials: BS
authors.lastname: Glisson
authors.forename: K S Clifford
authors.initials: KS
authors.lastname: Chao
authors.forename: David L
authors.initials: DL
authors.lastname: Schwartz
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Chronowski
authors.forename: Adel K
authors.initials: AK
authors.lastname: El-Naggar
authors.forename: Adam S
authors.initials: AS
authors.lastname: Garden
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use; D002294:Carcinoma, Squamous Cell / Q000401:mortality / Q000532:radiotherapy* / Q000556:secondary; D019583:Dose Fractionation, Radiation; D005260:Female; D005500:Follow-Up Studies; D006258:Head and Neck Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D037981:Neck Dissection / Q000379:methods; D009382:Neoplasms, Unknown Primary / Q000401:mortality / Q000473:pathology; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects; D012074:Remission Induction / Q000379:methods; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents