Intensity-modulated radiotherapy for cervical lymph node metastases from unknown primary cancer.
OBJECTIVE
To compare the effectiveness of intensity-modulated radiotherapy (IMRT) and conventional (two-dimensional) radiotherapy in the treatment of cervical lymph node metastases from unknown primary cancer (UPC).


METHODS
Between February 2003 and September 2006, 23 patients with UPC of squamous cell carcinoma were treated with IMRT. Extended putative mucosal and bilateral nodal sites were irradiated to a median dose of 66 Gy. In 19 patients, IMRT was performed after lymph node dissection, and in 4 patients primary radiotherapy was given. The conventional radiotherapy group (historical control group) comprised 18 patients treated to a median dose of 66 Gy between August 1994 and October 2003.


RESULTS
Twenty patients completed treatment. As compared with conventional radiotherapy, the incidence of Grade 3 acute dysphagia was significantly lower in the IMRT group (4.5% vs. 50%, p = 0.003). By 6 months, Grade 3 xerostomia was detected in 11.8% patients in the IMRT group vs. 53.4% in the historical control group (p = 0.03). No Grade 3 dysphagia or skin fibrosis was observed after IMRT but these were noted after conventional radiotherapy (26.7%, p = 0.01) and 26.7%, p = 0.03) respectively). With median follow-up of living patients of 17 months, there was no emergence of primary cancer. One patient had persistent nodal disease and another had nodal relapse at 5 months. Distant metastases were detected in 4 patients. The 2-year overall survival and distant disease-free probability after IMRT did not differ significantly from those for conventional radiotherapy (74.8% vs. 61.1% and 76.3% vs. 68.4%, respectively).


CONCLUSIONS
Use of IMRT for UPC resulted in lower toxicity than conventional radiotherapy, and was similar in efficacy.
Madani
Indira
I
Department of Radiotherapy, Ghent University Hospital, Ghent, Belgium. indira@krtg1.ugent.be
Vakaet
Luc
L
Bonte
Katrien
K
Boterberg
Tom
T
De Neve
Wilfried
W
D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy*; D002574:Cervical Vertebrae; D005260:Female; D006258:Head and Neck Neoplasms / Q000532:radiotherapy*; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009382:Neoplasms, Unknown Primary / Q000532:radiotherapy*; D020266:Radiotherapy, Conformal / Q000379:methods*; D016896:Treatment Outcome