Clinicopathological features and clinical outcomes in individuals with Krukenberg tumors of colorectal origin.

Abstract

191 Background: Krukenberg tumors (KT) are metastases to the ovary generally originating from a gastrointestinal primary such as colorectal carcinoma. The prognosis is poor with KT, and clinicopathological features associated with clinical outcomes have not been extensively studied. The study aimed to investigate the associations of clinicopathological features with outcomes in patients with KT of colorectal carcinoma (CRC) origin. Methods: This retrospective study utilized medical records and patient registries to identify 160 patients with a confirmed histopathological diagnosis of KT at Stanford University Medical Center between 2000 and 2020. Data collection included demographics, historical, clinicopathological, treatment and outcome variables. The primary tumor type was (N, %): CRC (101, 63.1%); gastric (24, 15%), breast (13, 8.1%); small bowel (10, 6.2%), other (12, 7.5%). Statistical analysis was performed using Chi-squared, Mann-Whitney U, and log-rank Kaplan-Meier analysis. Results: Analysis of the CRC cohort subdivided by location of the primary, N: 45 vs. 56, right colon (R) vs. left colon (L) revealed no significant difference in median age at diagnosis of KT, race/ethnicity, oligometastatic disease, histopathological differentiation or ovarian tumor volume. Patients with R vs L sided CRC primaries had a higher proportion of synchronous presentation at the time of KT diagnosis (75.6% vs 41.1%, R vs L, p<0.001). Time to progression was not different, but overall survival (OS) was shorter in R CRC (767 vs. 1246 days, R vs. L, p <0.01). By Kaplan-Meier analysis, patients with R CRC had a shorter OS (log-rank p=0.016). In the subgroup with unilateral KT, R sided CRC primaries involved the R ovary (85%) whereas L-sided CRC primaries involved the L ovary (70%) ( χ2, p<0.002). Patient with bilateral (B) versus unilateral (U) had a larger ovarian tumor volume (2,073cm3 vs. 307 cm3, p<0.01) but no difference in oligometastatic disease, chronicity, time to progression or overall survival. There was no statistical difference (p=0.93) between the association of bilateral KT inter-ovarian tumor size and CRC Laterality within individual patients. Conclusions: In this study, KT tumors predominantly originate from CRC. The clinical features of R versus L CRC, such as chronicity and OS are conveyed prognostically in patients with KT. Individuals with L CRC exhibited a better overall prognosis compared to those with R CRC. In patients with unilateral KT metastasis to ipsilateral ovary is significantly associated with location of CRC and is suggestive of a retrograde lymphatic or transcoelomic route of metastatic spread. Further studies are needed to confirm these findings and to elucidate ovarian organ tropism mediators that facilitate development and growth in metastatic ovarian cancer.