The risk of secondary malignancies over 30 years after the treatment of non‐Hodgkin lymphoma

Abstract

BACKGROUND Survivors of non‐Hodgkin lymphoma (NHL) are at increased risk for developing secondary malignancies. For the current study, the authors quantitated this risk in a group of NHL survivors over 30 years of follow‐up. METHODS Standardized incidence ratios (observed‐to‐expected [O/E] ratio) and absolute excess risk of secondary malignancies were assessed in 77,876 patients who were diagnosed with NHL between 1973 and 2001 from centers that participated in the National Cancer Institute's Surveillance, Epidemiology, and End Results Program. RESULTS There were 5638 patients who developed secondary malignancies, significantly more than the endemic rate (O/E, 1.14; P<.001). Overall, irradiated patients had a similar risk of secondary malignancies compared with unirradiated patients (relative risk, 1.04; 95% confidence interval, 0.98‐1.10; P = .21). Irradiated patients had excess risk for sarcomas, breast cancers, and mesothelioma compared with unirradiated survivors (P<.05). Patients age <25 years at the time of their NHL diagnosis had the highest relative increased risk (no radiation: O/E, 2.1; P<.05; radiation: O/E, 4.51; P<.05). Overall, no statistical difference was observed for secondary cancer incidence between females and males (O/E, 1.12 vs. 1.15, respectively). Female survivors of NHL were less likely to develop breast cancer than the general population (O/E, 0.85; P<.05), but women age <25 years at the time of their NHL diagnosis were more likely to develop breast cancer (no radiation: O/E, 2.1; P<.05; radiation: O/E, 4.51; P<.05). CONCLUSIONS The overall risk of secondary malignancies was increased for NHL survivors and varied according to age at NHL diagnosis, gender, and treatment. Cancer 2006. © 2006 American Cancer Society.

Therapeutic radiation for lymphoma

“…By using this number, any subsequent diagnosis of mesothelioma among patients with HL or NHL was identified, including any malignancies after a second malignancy. Similar to the study by Tward et al 19 patients with <2 months of follow-up were excluded, including those who had 2 malignancies diagnosed within a 2-month period. The month and year of diagnosis were extracted along with age at diagnosis, vital status, radiation treatment, surgical treatment, and duration of follow-up.…”

“…[45][46][47] It is only very recently, however, that epidemiology studies have shown associations between mesothelioma and radiation treatment for NHL and testicular cancer. 7,19 Travis et al 7 used SEER data through 2001, enhanced by data from other population-based registries in Canada and Europe, to identify 40,576 survivors of testicular cancer who were followed for second cancers. A statistically significant increased risk of pleural mesothelioma was reported among men who received supradiaphragmatic radiation (relative risk [RR], 4.0: 95%CI, 2.0-8.1).…”

“…A statistically significant increased risk of pleural mesothelioma was reported among men who received supradiaphragmatic radiation (relative risk [RR], 4.0: 95%CI, 2.0-8.1). Tward et al 19 used the SEER Program to identify 77,876 patients with NHL who were diagnosed from 1973 to 2001. Second primary malignancies were identified among these patients from the same database stratified by radiation treatment.…”

“…2,[12][13][14][15][16][17][18] Studies of radiation effects for both HL and NHL reported that the greatest increase in breast cancer risk occurred among women who were irradiated at a young age. 18,19 Malignant pleural mesothelioma is a rare, fatal solid tumor that typically has a long latency after asbestos exposure. It is estimated that !85% of mesothelioma diagnoses are attributed to past asbestos exposure, which, until recently, was the only established cause of this disease in the United States.…”

“…However, 2 more recent studies that used updated SEER data through 2001 have reported statistically significant increases in malignant mesothelioma associated with radiotherapy for testicular cancer and NHL. 7,19 Given the existing reports of increased risks of mesothelioma associated with radiotherapy for testicular cancer and NHL and using more recent SEER data, in this report, we provide a 10-year update to the study by Neugut et al 40 for HL survivors who were treated with radiation. We also added 2 more years of SEER data to the database of survivors of NHL recently analyzed by Tward et al 19 …”