Risk of Head and Neck Cancer in Patients With Prior Hematologic Malignant Tumors.

Importance: More than 1.3 million people in the United States have a hematologic malignant tumor currently or in remission. Previous studies have demonstrated an increased risk of secondary neoplasms in patients with hematologic malignant tumors, but research specifically on the risk of head and neck solid tumors in patients with prior hematologic malignant tumors is limited. Objectives: To examine a possible association between prior hematologic malignant tumors and risk of head and neck cancer and to assess the overall survival (OS) among these patients. Design, Setting, and Participants: This retrospective analysis used the Veterans Affairs (VA) Corporate Data Warehouse (CDW) to identify patients with diagnoses of hematologic malignant tumors and head and neck cancers. All patients in the VA CDW with a birthdate between January 1, 1910, and December 31, 1969, were included, for a cohort of 30 939 656 veterans. Data analysis was performed from August 15, 2018, to January 31, 2019. Exposures: Outpatient problem lists were queried for diagnoses of hematologic malignant tumor and associated malignant tumors using International Classification of Diseases, Ninth Revision (ICD-9) and International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) codes to categorize patients by history of hematologic malignant tumors. Main Outcomes and Measures: Presence of head and neck cancer was determined from ICD-9 and ICD-10 codes of outpatient problem lists, and cancers were grouped by subsite. The OS was determined from date of death or last outpatient visit date. Results: Of 30 939 656 patients (27 636 683 [89.3%] male; 13 971 259 [45.2%] white), 207 322 patients had a hematologic malignant tumor, of whom 1353 were later diagnosed with head and neck cancer. A history of hematologic malignant tumors was significantly associated with overall aerodigestive tract cancer, with a relative risk (RR) of 1.6 (95% CI, 1.5-1.7), as well as oral cavity (RR, 1.7; 95% CI, 1.5-1.9), oropharynx (RR, 1.7; 95% CI, 1.5-1.9), larynx (RR, 1.3; 95% CI, 1.2-1.5), nasopharynx (RR, 2.8; 95% CI, 2.1-3.9), sinonasal (RR, 3.0; 95% CI, 2.2-4.1), salivary gland (RR, 2.8; 95% CI, 2.4-3.3), and thyroid (RR, 2.1; 95% CI, 1.9-2.4) tumors on subsite analysis. A prior hematologic malignant tumor was also negatively associated with 2-year and 5-year OS for multiple subsites. Conclusions and Relevance: A prior diagnosis of hematologic or associated malignant tumors was associated with an increased risk of solid head and neck cancers in a range of subsites. In addition, for several head and neck cancer subsites, patients with prior hematologic malignant tumors had worse 2-year and 5-year OS. These results indicate that a prior hematologic malignant tumor may be an adverse risk factor in the development and progression of head and neck cancer.