Prognostics of Systemic Malignancy ICD-O Topography and Morphology Types on Brain Metastases: An NCDB Time-to-event Cohort

Am J Clin Oncol. 2023 Nov 1;46(11):475-485. doi: 10.1097/COC.0000000000001034. Epub 2023 Aug 7.

Abstract

Background: The primary site and histology of systemic malignancy are known predictors of progression to brain metastases (BM). We investigated the combinational interactions of International Classification of Diseases for Oncology (ICD-O) primary topography and morphology types on the survival of BM after adjusting for relevant clinical and demographic prognostic factors.

Methods: The cohort included all adult patients with BM at diagnosis of an invasive malignancy in the National Cancer Database (2010 to 2018). The sample consisted of 180,150 entries out of 14,279,749 cancer patients screened. A survival analysis of the topography-specific and histology-specific time to death was performed. Multivariate Cox regression revealed violations of the proportional hazard assumption for multiple covariates. Parametric models using a log-logistic distribution best described the population survival pattern.

Results: The primary topography "prostate" and morphology "choriocarcinoma" provided the strongest survival benefit among ICD-O types, whereas BM from prostate demonstrated a 14-month median overall increase in survival probability. Favorable prognostics were BM from breast, bone/joints, and testis; also, the morphologies of carcinoid tumor, mature B-cell lymphoma, and papillary adenocarcinoma. Poor prognostics were BM from gastrointestinal (liver, biliary tree, pancreas, and gallbladder) and gynecologic malignancies. All morphologies of spindle cell carcinoma, hemangiosarcoma, undifferentiated carcinoma, Ewing sarcoma, pseudosarcomatous carcinoma, renal cell carcinoma/sarcomatoid, signet ring cell carcinoma, spindle cell sarcoma, and squamous cell carcinoma/spindle cell were associated with poor survival.

Conclusions: This is the largest cohort providing an unbiased estimate of the adjusted ICD-O topography and morphology effect sizes. The results can be summarized as a booklet for prognostic classification of disease in patients with BM secondary to systemic malignancy.