Comparing the eighth and the seventh editions of the American Joint Committee on Cancer staging system and the Brigham and Women's Hospital alternative staging system for cutaneous squamous cell carcinoma: Implications for clinical practice.

BACKGROUND

The new eighth edition of the American Joint Committee on Cancer staging system (AJCC-8) incorporates changes regarding cutaneous squamous cell carcinoma (CSCC).

OBJECTIVES

We aimed to compare the AJCC-8 staging system with the previous seventh edition of the AJCC staging system (AJCC-7) and the Brigham and Women's Hospital (BWH) alternative staging system to identify their usefulness and the utility of their risk factors in defining prognostic groups in CSCC.

METHODS

A series of 186 CSCCs of the head and neck were retrospectively collected. All 3 staging systems were compared from the standpoint of their ability to predict poor prognosis. Binary logistic regression models were built to determine which risk factors were most relevant.

RESULTS

Poor prognosis was mainly associated with stage T2 of the AJCC-7, with stages T2b/T3 of the BWH system, and with stage T3 of the AJCC-8. The AJCC-8 and the BWH staging systems displayed overlap with each another in predicting poor prognosis, and both were superior to the AJCC-7. The new risk factors incorporated into the AJCC-8 and the poor degree of differentiation were independently associated with poor outcome.

LIMITATIONS

Retrospective study and few cases with bone invasion.

CONCLUSIONS

The AJCC-8 is more distinctive, monotonous, and homogeneous than the AJCC-7 and shows some overlap with the BWH system in stratification of tumors.