Validation of the eighth edition AJCC staging system in early T1 to T2 oral squamous cell carcinoma

Abstract

Background To validate the newly proposed American Joint Committee on Cancer (AJCC) eighth edition staging in early T1 and T2 oral cavity cancers and its effect in predicting tumour control. Methods Retrospective analysis of treatment outcomes of 441 T1 to T2 oral squamous cell carcinoma (OSCC). Overall survival (OS), disease‐specific survival (DSS), and tumour control were calculated and compared between the AJCC 7 and 8 staging systems. Results The 5‐year OS was 78% and 61% for T1 and T2 tumours, respetively (P < 0.001) (AJCC 7) vs 87% and 67% (P < 0.001) (AJCC 8). The 5‐year DSS was 78% and 61% for T1 and T2, respectively (P < 0.001) (AJCC 7) vs 89% and 71% (P < 0.001) (AJCC 8). For stages I and II tumours the 5‐year OS was 81% and 76%, respectively (P < 0.302) (AJCC 7) vs 87% and 73% (P < 0.017) (AJCC 8). The 5‐year DSS was 83% and 82% (P < 0.222) vs 89% and 77% (P < 0.016). With the AJCC eighth edition the 5‐year local, regional, and distant control rates for T1 vs T2 tumours were 85% vs 74% (P = 0.003), 95% vs 77% (P = 0.001), and 95% vs 80% (P = 0.014), respectively. Conclusion The AJCC 8th staging system provided for more accurate prediction of OS, DSS, and disease control in early oral cavity cancers.

Comparison of the seventh and eighth editions American Joint Committee Cancer classification system in oral cavity squamous cell cancers

“…(112 patients, Japan) and Murthy et al . (441 only T1‐2 cancers, India) also showed that new staging system correctly reflects prognosis as compared to older one. One more study from the United States by Cramer et al .…”

“…With regard to their survival outcomes, we found that patients with upstaged disease had poor survival outcomes as compared to those with retained stage classification. In addition, CI, AIC and hazard modeling all favor new staging system for predicting outcomes, especially for TCs Japan) 12 and Murthy et al (441 only T1-2 cancers, India) 13 also showed that new staging system correctly reflects prognosis as compared to older one. One more study from the United States by Cramer et al concluded marginally improved prognostic ability for AJCC8 (0.699-0.704).…”

Risk stratification in oral squamous cell carcinoma using staging of the eighth American Joint Committee on Cancer: Systematic review and meta‐analysis

“…Therefore, 20 studies were eligible as they evaluated the prognostic performance of AJCC 8 in OSCC (Figure 1). Of these, seven studies were from Asia, [18][19][20][21][22][23][24] four were from Australia, 12,[25][26][27] four from Europe, [28][29][30][31] four from North America, 14,[32][33][34] and one from South America. 35 In addition, a Brazilian cohort was analyzed in one of the published studies combined with a Finnish cohort.…”

“…28 Most studies included different subsites of OSCC, and only four studies included oral tongue SCC without any other subsite. 18,28,29,33 Overlapping studies were from Australia 12,25,26 and India 20,21 ; and they were not included together in the present meta-analysis.…”

“…26,33 Moreover, many other studies that did not report the C-index or AIC have reported that AJCC 8 allows for better risk stratification (than AJCC 7) for OSCC cases as indicated by the prognostic values and survival curves. 20,21,[27][28][29][30] Interestingly, AJCC 8 has demonstrated a good prognostic performance in recent studies on gastric cancer, 54,55 breast cancer 56,57 and lung cancer. 58 In cutaneous squamous cell carcinoma of the head and neck, a weaker prognostic performance (C-index 0.58 for overall survival and 0.61 for disease-specific survival) has been reported.…”