Identification of a high-risk group among patients with oral cavity squamous cell carcinoma and pT1-2N0 disease

Int J Radiat Oncol Biol Phys. 2012 Jan 1;82(1):284-90. doi: 10.1016/j.ijrobp.2010.09.036. Epub 2010 Nov 13.

Abstract

Purpose: In the American Joint Committee on Cancer 2010 classification system, pT1-2N0 oral cavity squamous cell carcinoma (OSCC) is considered an early-stage cancer treatable with surgery alone (National Comprehensive Cancer Network 2010 guidelines). Our aim was to evaluate the feasibility of surgery alone for pT1-2N0 OSCC patients.

Methods and materials: Among 1279 previously untreated OSCC patients referred to our hospital between January 1996 and May 2008, we identified 457 consecutive patients with pT1-2N0 disease. All had radical tumor excision with neck dissection. A total of 387 patients showing pathologic margins greater than 4 mm and treated by surgery alone were included in the final analysis. All were followed up for at least 24 months after surgery or until death. The 5-year rates of control, distant metastasis, and survival were the main outcome measures.

Results: The 5-year rates in the entire group of pT1-2N0 patients were as follows: local control, 91%; neck control, 92%; distant metastases, 1%; disease-free survival, 85%; disease-specific survival, 93%; and overall survival, 84%. Multivariate analysis identified poor differentiation and pathologic tumor depth of 4 mm or greater as independent risk factors for neck control, disease-free survival, and disease-specific survival. A scoring system using poor differentiation and tumor depth was formulated to define distinct prognostic groups. The presence of both poorly differentiated tumors and a tumor depth of 4 mm or greater resulted in significantly poorer 5-year neck control (p < 0.0001), disease-free (p < 0.0001), disease-specific (p < 0.0001), and overall survival (p = 0.0046) rates.

Conclusion: The combination of poor differentiation and pathologic tumor depth of 4 mm or greater identified a subset of pT1-2N0 OSCC patients with poor outcome, who may have clinical benefit from postoperative adjuvant radiotherapy.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Analysis of Variance
  • Carcinoma, Squamous Cell / mortality
  • Carcinoma, Squamous Cell / pathology
  • Carcinoma, Squamous Cell / radiotherapy
  • Carcinoma, Squamous Cell / secondary
  • Carcinoma, Squamous Cell / surgery*
  • Disease-Free Survival
  • Feasibility Studies
  • Female
  • Humans
  • Male
  • Middle Aged
  • Mouth Neoplasms / mortality
  • Mouth Neoplasms / pathology
  • Mouth Neoplasms / radiotherapy
  • Mouth Neoplasms / surgery*
  • Neck Dissection*
  • Neoplasm Staging
  • Radiotherapy, Adjuvant
  • Survival Rate
  • Treatment Outcome
  • Tumor Burden