190P - Quantitative serum tumor markers (CEA, CA19-9, and CA-125) are independently predictive of survival in patients with appendiceal adenocarcinoma

Background

Although grade is strongly predictive of survival, no other prognostic or predictive biomarkers have been validated to help guide therapeutic decision making in Appendiceal adenocarcinomas (AA). Here we investigated the clinical utility of the serum tumor markers CEA, CA19-9, and CA-125 by association with survival and tumor molecular features.

Methods

The MD Anderson patient database was queried to identify a total of 1,322 patients diagnosed with of AA between 1997 to 2022 with at least one TM measured. Elevation of TM defined as above laboratory ULN (CEA > 3 ng/mL, CA 19-9 > 37 U/mL, and CA-125 > 37 U/mL, highly elevated defined as top 10^th percentile (CEA > 100.4 ng/mL, CA 19-9 > 337.5 U/mL, and CA-125 > 41.8 U/mL).

Results

CEA, CA19-9 and CA125 were elevated in 56%, 34%, and 37% of patients, respectively, 63.8% had at least one elevated. The proportion of patients with elevation of each TM did not differ in high- vs low-grade tumors or by histologic subtype (mucinous, colonic, goblet, signet ring). CEA stratified patients by survival with median not-yet-reached for patients with normal CEA vs 182 mo for those with elevated CEA vs 96 mo for those with highly elevated CEA (log-rank p < 0.0001), 5-year OS was 95% vs 82% vs 61% for normal, elevated, and highly elevated, respectively. The prognostic effect of CEA was independent of grade, with 5-year OS (99%, 93%, 69%, log-rank p < 0.0001) for low-grade and (91%, 73%, 55%, log-rank p < 0.0001). Similar survival stratification was seen for CA19-9 (92%, 84%, 66%, log-rank p < 0.0001) and CA-125 (93%, 70%, 60%, log-rank p < 0.0001). CEA was more correlated with CA-19-9 (pearson r = 0.62) than CA-125 (r = 0.29). Elevation of multiple TM was associated with worse prognosis; HR relative to patients with no TM elevated was 4.9 (p = 6.0e-6), 8.9 (p = 6.5e-12), and 16.2 (p = 8.0e-16), for 1, 2, or all 3 TM in multivariate cox model of survival including gender, race, age, grade, and histologic subtype.

Conclusions

Elevation of CEA, CA19-9 and CA125 are independently associated with poor prognosis in patients with appendiceal cancer, all three should be measured. Future efforts to evaluate incorporation of TM into clinical staging are warranted.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

University of Texas MD Anderson Cancer Center, Cancer Prevention Research Institute of Texas.

Disclosure

J. P. Y-C. Shen: Financial Interests, Personal, Other, general consultation and expert testimony: ShenJPMD Inc; Financial Interests, Personal, Other, advisory board: Engine Biosciences, NaDeNo Nanosciences; Financial Interests, Institutional, Coordinating PI, research project: Celsius Therapeutics; Financial Interests, Institutional, Other, research funding for pilot project: BostonGene. M.J. Overman: Financial Interests, Personal, Advisory Board: Roche, BMS, MedImmune, Merck, Amgen, Takeda, Janssen, Pfizer, Array, Gritstone, Nouscom, Atreca, Bayer; Financial Interests, Institutional, Coordinating PI: Roche, Lilly, Merck, BMS, Phanes, Nouscom. All other authors have declared no conflicts of interest.