Abstract
The prognostic stratification of the current AJCC/UICC TNM classification
for adrenocortical carcinoma (ACC) has been validated in only a few studies. In
this study, it was hypothesized that redefining the T category cut-off would
result in a significant improvement in estimated stage-related survival. In 935
patients with ACC from the SEER database, optimal cut-off values based on tumor
size were first determined to redefine T1 and T2 categories. Cox proportional
hazards regression analysis and receiver operating characteristics (ROC) were
then used to determine the prognostic value of the revised version. A new
cut-off value of 9.5 cm tumor size was established to differentiate
between T1 and T2 tumors, leading to a revised TNM classification. As a result,
a more homogeneous distribution of patients with ACC across all stages was
observed. Notably, the predictive value of the newly proposed TNM classification
in the ROC analysis exceeded that of the 7th and 8th editions of the
AJCC/UICC classification system. Finally, the prognostic superiority of
the revised TNM classification was confirmed in a multivariate Cox proportional
hazards regression model. In conclusion, the present study demonstrates that
updating the current staging system with revised T1 and T2 categories
significantly improves the prediction of cancer-specific survival (CSS) in
patients with ACC.
Key words
adrenocortical carcinoma - tumor staging - TNM classification - UICC - AJCC
