Neutron vs photon irradiation of inoperable salivary gland tumors: results of an RTOG-MRC Cooperative Randomized Study.
A total of 32 patients with inoperable, recurrent or unresectable malignant salivary gland tumors were entered on a randomized RTOG/MRC study comparing fast neutron radiotherapy with conventional photon radiotherapy. Twenty-five patients were entered from the United States and 7 patients were entered from Scotland. Seventeen patients were randomized to receive neutrons and 15 patients were randomized to receive photons. Sixty-one percent of the neutron-treated patients and 75% of the photon-treated patients presented with inoperable or unresectable tumors, while 39% of the neutron-treated and 25% of the photon-treated patients had recurrent disease. Twenty-five patients were study-eligible and analyzable. The minimum follow-up time is 2 years. The complete tumor clearance rates at the primary site were 85% (11/13) for neutrons and 33% (4/12) for photons following protocol treatment (p = 0.01). The complete tumor clearance rates in the cervical lymph nodes were 86% (6/7) for neutrons and 25% (1/4) for photons. The overall loco/regional complete tumor response rates were 85% and 33% for neutrons and photons respectively. The loco/regional control rates at 2 years for the 2 groups are 67% for neutrons and 17% for photons (p less than 0.005). The 2-year survival rates are 62% and 25% for neutrons and photons respectively (p = 0.10). These findings are consistent with previously published uncontrolled series.
Griffin
T W
TW
Department of Radiation Oncology, University of Washington Hospital/School of Medicine, Seattle 98195.
Pajak
T F
TF
Laramore
G E
GE
Duncan
W
W
Richter
M P
MP
Hendrickson
F R
FR
Maor
M H
MH
D000230:Adenocarcinoma / Q000532:radiotherapy; D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000532:radiotherapy; D003528:Carcinoma, Adenoid Cystic / Q000532:radiotherapy; D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy; D002986:Clinical Trials as Topic; D005214:Fast Neutrons; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009502:Neutrons; D011379:Prognosis; D011446:Prospective Studies; D011897:Random Allocation; D012468:Salivary Gland Neoplasms / Q000532:radiotherapy*