Overall and disease‐specific survival of Hodgkin lymphoma survivors who subsequently developed gastrointestinal cancer

BACKGROUND: Hodgkin lymphoma (HL) survivors have an increased risk of gastrointestinal (GI) cancer. This study aims to evaluate whether survival of patients who survived HL and developed GI cancer differs from survival of first primary GI cancer patients. METHODS: Overall and cause‐specific survival of GI cancer patients in a HL survivor cohort (GI‐HL, N = 104, including esophageal, gastric, small intestinal, and colorectal cancer) was compared with survival of a first primary GI cancer patient cohort (GI‐1, N = 1025, generated by case matching based on tumor site, gender, age, and year of diagnosis). Cox proportional hazards regression was used for survival analyses. Multivariable analyses were adjusted for GI cancer stage, grade of differentiation, surgery, radiotherapy, and chemotherapy. RESULTS: GI‐HL cancers were diagnosed at a median age of 54 years (interquartile range 45‐60). No differences in tumor stage or frequency of surgery were found. GI‐HL patients less often received radiotherapy (8% vs 23% in GI‐1 patients, P < 0.001) and chemotherapy (28% vs 41%, P = 0.01) for their GI tumor. Compared with GI‐1 patients, overall and disease‐specific survival of GI‐HL patients was worse (univariable hazard ratio (HR) 1.30, 95% confidence interval (CI) 1.03‐1.65, P = 0.03; and HR 1.29, 95% CI 1.00‐1.67, P = 0.049, respectively; multivariable HR 1.33, 95% CI 1.05‐1.68, P = 0.02; and HR 1.33, 95% CI 1.03‐1.72, P = 0.03, respectively). CONCLUSIONS: Long‐term overall and disease‐specific survival of GI cancer in HL survivors is worse compared with first primary GI cancer patients. Differences in tumor stage, grade of differentiation, or treatment could not explain this worse survival.