Increased risk of salivary gland tumors after low-dose irradiation.
OBJECTIVE
To assess the risk of neoplastic development among persons exposed to scalp irradiation.


METHODS
Historical cohort study initially; prospective follow-up subsequently.


METHODS
Two control groups--population and siblings--matched for age, sex, ethnic origin, and year of immigration. Follow-up from time of irradiation (1950s) until the end of 1991. Linkage with nationwide cancer registry.


RESULTS
A 4.5-fold incidence of cancer (P < .01) and a 2.6-fold increase of benign tumors were noted. The mean length of latency period until tumor development was 11 years for malignant tumors and 21.5 years for benign. A clear dose response effect for both cancer and benign tumors was demonstrated.


CONCLUSIONS
The study confirms the role of radiation in salivary gland carcinogenesis. It indicates a need for better awareness, a comprehensive examination, and long-term follow-up of patients who have been subjected to head and neck radiation.
Department of Clinical Epidemiology, Chaim Sheba Medical Center, and The Stanley Steyer Institute for Cancer Epidemiology and Research, Tel Aviv University School of Medicine, Tel Hashomer, Israel.
B
B
Modan
A
A
Chetrit
E
E
Alfandary
A
A
Tamir
A
A
Lusky
M
M
Wolf
O
O
Shpilberg
D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D016371:Cranial Irradiation / Q000009:adverse effects*; D004307:Dose-Response Relationship, Radiation; D004641:Emigration and Immigration; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007223:Infant; D007557:Israel; D008297:Male; D009381:Neoplasms, Radiation-Induced / Q000208:ethnology / Q000209:etiology*; D012042:Registries; D012306:Risk; D012307:Risk Factors; D012468:Salivary Gland Neoplasms / Q000208:ethnology / Q000209:etiology*; D013997:Time Factors; D014006:Tinea Capitis / Q000532:radiotherapy*