Shortened telomeres in peripheral lymphocytes are associated to complex chromosome anomalies and to second cancers in Hodgkin's lymphoma patients

6512 Background: Longer telomeres protect against chromosome instability. Telomeres and chromosomes of peripheral lymphocytes were assessed in Hodgkin Lymphoma (HL) patients, in relation to second cancer (SC). Methods: 3 cohorts of HL patients: untreated HL (n = 70, mean age 33); SC after HL (n = 28 [myelodysplasia 2, non Hodgkin L 6, solid tumor 20], mean age 52); no disease or complication at long term (NED HL, n = 18, mean age 58). 2 types of controls: healthy donors (n = 30, mean age 32.5); untreated solid tumors (n = 70, mean age 41). Peripheral blood was irradiated in vitro (200 & 400 cGy). Chromosomal abnormalities were scored by FISH painting of chromosomes 1, 3 and 4. Telomere length was measured by TRF assay & Q-FISH. Results: In circulating lymphocytes of untreated HL, it was observed shorter telomeres (mean 8.3kb [5.8–12kb]), more frequent spontaneous chromosomal anomalies & increased in vitro radiosensitivity, than in both control populations (f.i. donors: mean 11.7kb [10.5–12.7kb], p<10–3). ...