Alterations in hormone levels after adjuvant chemoradiation in male rectal cancer patients.
OBJECTIVE
To evaluate follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone levels after postoperative chemoradiation in men with rectal cancer.


METHODS
Forty-three men with rectal cancer had baseline and postchemoradiation FSH, LH, and testosterone measured. Adjuvant chemoradiation consisted of two 5-day cycles of bolus 5-fluorouracil (5-FU) every 4 weeks at a dose of 500 mg/m(2)/d followed by concurrent chemoradiation followed by two additional 5-day cycles of 5-FU at a dose of 450 mg/m(2)/d. Continuous-infusion 5-FU at 225 mg/m(2)/d was given during radiation. Pelvic radiation consisted of a three- or four-field technique with a median dose of 54.0 Gy in 30 fractions.


RESULTS
Median follow-up was 6.1 years. Mean baseline FSH levels increased from 5.3 to a peak of 23.9 IU/L (p < 0.001) 13-24 months after chemoradiation. Mean baseline LH levels increased from 4.3 to a peak of 8.5 IU/L (p < 0.001) within 6 months after chemoradiation. Mean testosterone levels decreased from 15.4 nmol/L at baseline to 8.0 nmol/L more than 4 years after chemoradiation. Mean testosterone to mean LH ratio decreased from 4.4 at baseline to 1.1 after 48 months posttreatment, suggesting a continued decrease in Leydig cell function with time. Testicular dose was measured in 5 patients. Median dose was 4 Gy (range, 1.5-8.9 Gy).


CONCLUSIONS
Chemoradiation in men with rectal cancer causes persistent increases in FSH and LH levels and decreases in testosterone levels.
Yoon
Frederick H
FH
Department of Radiation Oncology, Princess Margaret Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada.
Perera
Francisco
F
Fisher
Barbara
B
Stitt
Larry
L
D000328:Adult; D000368:Aged; D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use; D017024:Chemotherapy, Adjuvant; D005472:Fluorouracil / Q000627:therapeutic use; D005640:Follicle Stimulating Hormone / Q000097:blood*; D006801:Humans; D007986:Luteinizing Hormone / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011879:Radiotherapy Dosage; D018714:Radiotherapy, Adjuvant; D012004:Rectal Neoplasms / Q000097:blood / Q000188:drug therapy* / Q000532:radiotherapy* / Q000601:surgery; D013739:Testosterone / Q000097:blood*
D000964:Antimetabolites, Antineoplastic; D013739:Testosterone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D005472:Fluorouracil