Y chromosome loss is a frequent event in Barrett’s adenocarcinoma and associated with poor outcome

Introduction The loss of the Y chromosome in various malignant diseases has been described previously. There are no reliable information on the actual frequency, significance and homogeneity of Y chromosome loss (LoY) in esophageal adenocarcinoma (EAC).

Aim The study analyzed the relevance of the Y chromosome in EAC.

Material and methods 400 male EAC including lymph-node metastases were analyzed with commercially available Y chromosome specific fluorescence in-situ probes. The results were correlated with molecular and immunohistochemical markers and clinicopathological aspects.

Results The entire cohort (n=400) showed a singular LoY of one chromosome arm in 1.0% (q-arm) and 2.8% (p-arm), complete LoY in 52.5%. LoY was strongly associated with shortened overall-survival (OS). Patients with preserved Y chromosome had a median OS of 58.8 months, patients with LoY an OS of 19.4 months (p < 0.001). Multivariate analysis showed LoY as an independent prognostic marker with a hazard ratio of 1.835 (95% CI 1.233 - 2.725). LoY correlated with TP53 mutations (p = 0.003), KRAS amplification (p = 0.004), loss of ARID1a (p = 0.045) and presence of LAG3 (p = 0.018).

Conclusions Loss of the Y chromosome is a very common phenomenon in EAC. The LoY is heterogeneously distributed within the tumor, but corresponding lymph node metastases frequently show homogeneous LoY, indicating a selection and metastasizing advantage with poor prognosis. Also, an influence on the tumor microenvironment is likely. To date, the male predominance of EAC (7 - 9:1) is unclear, so genetic explanatory models are favored. Our data suggest that LoY has to be seen in a larger functional context. Understanding this context may shed light on the gender bias of EAC incidence.

Publikationsverlauf

Artikel online veröffentlicht:
08. September 2020