Disparities in post-survivorship psychiatric diagnoses among adult cancer patients in a multi-center academic health system

Background: Cancer patients experience substantial psychological burden, yet mental health conditions often remain unrecognized and untreated. Disparities in psychiatric care may exist across demographic groups, though comprehensive multi-cancer analyses examining these patterns are limited. Methods: We conducted a retrospective cohort study of 1,161,370 adult patients diagnosed with ten common cancers between January 2015 and September 2025 within the University of California Health system. Patients with pre-existing psychiatric diagnoses (12 months prior) or palliative-intent treatment were excluded. Primary outcomes were new-onset depression and anxiety diagnoses following cancer diagnosis. Multivariable logistic regression identified predictors of psychiatric diagnosis, adjusting for age, sex, race, ethnicity, insurance type, cancer type, and diagnosis year. Results: Of 1,161,370 patients (mean age 66.1 years, 52.9% female), 258,076 (22.2%) received new psychiatric diagnoses: 8.4% anxiety only, 5.7% depression only, and 8.2% both conditions. While 22.5% of patients with both conditions were diagnosed within one month of cancer diagnosis, 32-43% received diagnoses beyond 12 months, indicating delayed recognition. Significant demographic disparities emerged. Female patients had higher odds of depression (aOR=1.35, 95%CI:1.32-1.38) and anxiety (aOR=1.57, 95%CI:1.54-1.61) diagnoses than males. Asian patients had substantially lower odds of depression (aOR=0.58, 95%CI:0.56-0.59) and anxiety (aOR=0.56, 95%CI:0.55-0.58) compared to White patients. Hispanic/Latino patients had 51% lower odds of depression diagnosis (aOR=0.49, 95%CI:0.37-0.56). Patients with Medicaid had elevated odds of both depression (aOR=1.40, 95%CI:1.37-1.44) and anxiety (aOR=1.12, 95%CI:1.09-1.14) compared to privately insured patients. Breast cancer patients had the highest psychiatric diagnosis rates across cancer types, while prostate cancer patients had substantially lower odds (depression aOR=0.79, anxiety aOR=0.63). Conclusions: Nearly one-quarter of cancer patients receive new psychiatric diagnoses, yet substantial disparities exist by sex, race, ethnicity, insurance status, and cancer type. Delayed recognition with most diagnoses occurring beyond 12 months post-cancer highlights missed opportunities for early intervention. These findings suggest inequitable mental health recognition and care delivery in oncology. Systematic implementation of culturally appropriate screening, enhanced provider training, improved behavioral health integration throughout the cancer continuum, and policy reforms ensuring equitable mental health access are essential to address these disparities.