Margin to depth of invasion ratio as an indicator for stratifying close margins in early-stage oral squamous cell carcinoma.

OBJECTIVES: In early-stage oral squamous cell carcinoma (OSCC) patients, whether the margin-to-depth-of-invasion ratio (MDR) can assist in stratifying the prognosis remains unclear. METHODS: Patients diagnosed with early stage OSCC at National Taiwan University Hospital between January 2007 and December 2021 were reviewed. Patients with margin > 1 mm were classified into two groups: MDR < 0.5 and MDR ≥ 0.5. RESULTS: We analyzed 911 pT1-2N0M0 OSCC patients, 723 (79.36 %) with MDR ≥ 0.5 and 188 (20.64 %) with MDR < 0.5. Patients in the MDR < 0.5 group displayed a significantly higher local recurrence rate (odds ratio 2.81, p = 0.002) compared with MDR ≥ 0.5 group. The 5-year disease-free survival were 80.8 % for clear margin, 76.3 % for close margin (MDR ≥ 0.5), and 65.2 % for close margin (MDR < 0.5). The overall survival displayed a similar pattern, with 5-year rates of 88.3 % for clear margin, 86.8 % for close margin (MDR ≥ 0.5), and 75.0 % for close margin (MDR < 0.5). There were no significant overall survival differences between the two MDR ≥ 0.5 groups, but both were significantly superior to patients with MDR < 0.5 (p = 0.001; p = 0.01). After multivariant cox analysis, MDR < 0.5 was a significant risk factor for disease-free survival (p < 0.001). CONCLUSION: For early stage OSCC patients without positive margin (≦1mm), the survival outcome between MDR ≥ 0.5 group and MDR < 0.5 group was significantly different. The MDR < 0.5 group had significantly higher risk of local recurrence that may warrant adjuvant treatment.

Is the N2A Category Still Necessary for Oral Cancer Patients After Extranodal Extension Upgrade?

BACKGROUND: The presence of single-node metastasis (Ns) sometimes could be encountered in patients with oral squamous cell carcinoma (OSCC). The survival outcome for different Ns should be worthy of discussion. METHODS: Patients diagnosed with OSCC at the National Taiwan University Hospital between January 2007 and December 2018 were reviewed. All patients with Ns were classified into two groups: with and without extranodal extension (ENE). RESULTS: We analyzed 311 OSCC patients with Ns: 77 (24.76%) with and 234 (75.24%) without ENE. Lymph node (LN) >3 cm was the only significant factor associated with ENE (odds ratio 17.21, p < 0.001). The 5-year, disease-free survival of N1/N2A and N3B patients was 60.5% and 49.4%, respectively (p = 0.04), and the 5-year overall survival was 63.1% and 33.6%, respectively (p = 0.0001). Four fifths of Ns patients with LN >3 cm were upgraded to N3B category as ENE+. Postoperative radiotherapy (PORT) could provide significant benefit in regional control for Ns patients with (p = 0.03) and without (p = 0.0004) other adverse features. After multivariant Cox analysis, ENE+ was a modest and significant risk factor for disease-free (p = 0.08) and overall survival (p = 0.001). By contrast, the LN>3cm and N2A category were not significant risk factors for disease-free and overall survival. CONCLUSIONS: For OSCC patients with Ns, the survival outcome between N3B category and N1/N2A category was significantly different. After ENE+ upgrades (>80%), there were fewer N2A patients, and these patients became more comparable to N1 patients. PORT could significantly improve regional control for Ns patients.