Causes of death in patients with malignant adrenal tumours: a population-based analysis

This study aimed to characterize the causes of death and compute the risk of mortality due to each cause among patients with malignant adrenal tumours.

Data from malignant adrenal tumour patients were collected from the Surveillance, Epidemiology, and End Results (SEER) database (2004-2020). With reference data from the general population, the standardized mortality ratio (SMR) was calculated to assess all causes of death for malignant adrenal tumour patients.

A total of 1651 patients who died from primary malignant adrenal neoplasms were included; 854 cases of adrenocortical carcinoma (ACC)-related death, 118 cases of pheochromocytoma (PCC)-related death and 333 cases of neuroblastoma (NB)-related death were identified for further analysis. Approximately 56.78%~87.69% of patients died from primary malignant adrenal tumours, 7.21%~13.56% died from secondary malignant neoplasms (SMNs), and 5.11%~29.66% died from noncancer diseases. The main causes of death associated with SMNs included lung and bronchial cancer and soft tissue cancers, including heart, kidney and renal pelvis cancers; the noncancer causes of death included mainly heart disease, septicemia, and cerebrovascular disease. Compared with chemotherapy-naïve patients, chemotherapy-treated patients had higher SMRs of SMNs, including cancers of the colon (excluding the rectum), lung, bronchus, bones and joints; soft tissues, including the heart, kidney and renal pelvis; the brain and peripheral nervous system; and leukaemia, as well as nontumor diseases, including heart disease, septicemia, and cerebrovascular disease. Patients with NB were more likely to die from SMNs, including soft-tissue malignancies of the heart, bones and joints; brain; peripheral nervous system; the female genital system, including the ovary; leukaemia, including lymphocytic leukaemia; myeloid and monocytic leukaemia; and lymphoma, including non-Hodgkin lymphoma.

In addition to primary cancer, SMNs and nontumor diseases were important causes of death in patients with malignant adrenal tumours. Neuroblastoma patients and chemotherapy- treated patients are more likely to die from SMNs and should monitored closely.