Understanding Survival Factors in Lung Neuroendocrine Tumors: Insights from the California Cancer Registry

In 2019, Claire Mulvey, MD, received a NETRF Mentored Research Award to study the trends in incidence and survival outcomes for lung NETs. The goal was to learn more about who gets lung neuroendocrine tumors (NETs) and why so that researchers and clinicians can better understand how to improve care and reduce disparities for lung NET patients.

Lung NETs are the second most common primary site for NETs after gastrointestinal NETs. Traditionally, disease stage and grade have been used to predict clinical outcomes in lung NETs. However, Dr. Mulvey’s investigation went beyond these disease-specific elements to explore the role of social, demographic, and treatment factors in survival outcomes.

Dr. Mulvey recently published her results in the journal Endocrine-Related Cancer using the California Cancer Registry (CCR) to provide new insights into the factors influencing survival rates in well-differentiated lung NETs. The study examined data from 1992 to 2019, focusing on 6038 diagnosed cases of lung NETs in California (5569 typical, 469 atypical carcinoid).

The study found that the majority of these patients were women (70%) and non-Hispanic White (73%). The reason for the higher incidence in women is unclear, and more research is needed to understand the reasons behind this disparity. Further, non-Hispanic White individuals and individuals in the highest statewide socioeconomic status were more likely to be diagnosed early, before the disease metastasized, compared with other racial and ethnic groups.

The study revealed a strong association between sociodemographic factors and survival. Women, married individuals, and residents of high socioeconomic status (SES) neighborhoods exhibited better overall survival. Conversely, patients with Medicare or Medicaid/other public insurance had worse overall survival compared to those with private insurance.

Clinical features like tumor size and stage at diagnosis played a crucial role in survival outcomes. Interestingly, women and men showed differences in primary tumor size, indicating potential biological variations in tumor development.

Surgical interventions improved overall survival, affirming the critical role of surgery in managing lung NETs. Conversely, chemotherapy and radiation were associated with poorer outcomes, likely reflecting the severity of the disease in patients receiving these treatments.

This comprehensive study highlights that survival in lung NETs extends beyond the clinical characteristics of the tumor. Sociodemographic factors, including sex, marital status, socioeconomic status, and insurance type, significantly impact survival outcomes, pointing toward broader social determinants of health.

Dr. Mulvey and her team reported improved overall survival in the last two decades of their study compared to the first decade, suggesting that treatment advancements are improving outcomes for patients with lung NETs.

The findings underscore the need for tailored approaches in managing lung NETs, considering not just the clinical aspects but also the socioeconomic context of patients. Future research should focus on understanding the biological and social mechanisms behind these disparities and developing strategies to address them.