Profiling Cancer Risk in Oral Potentially Malignant Disorders – a Patient Cohort Study

Abstract

Background

Oral potentially malignant disorders harbour variable and unpredictable risk for squamous carcinoma development. Whilst current management strategies utilise histopathological diagnoses, dysplasia grading and targeted intervention for 'high risk' lesions, clinicians are unable to predict malignant potential.

Methods

Detailed, retrospective clinico-pathological analysis of potentially malignant lesions undergoing malignant transformation, from a 590 patient cohort treated by interventional laser surgery and followed for a mean of 7.3 years, was undertaken. Clinical outcome was documented at study census date (31 December 2014).

Results

99 patients (16.8%) developed cancer: 71 (12%) seen 'unexpectedly' upon excision and 28 (4.8%) progressing to malignancy at a median of 87.3 months post-surgery. 30 'unexpected' excisions were micro-invasive (42.3%) arising primarily in severely dysplastic precursors (75%) at ventro-lateral tongue and floor of mouth sites (54.5%); 1 patient (1.4%) had a cancer-related death, whilst 58 (81.7%) were disease free. 19 of 28 'progressive' cancers (67.9%) arose at new sites, with erythroleukoplakia a significant predictor of malignancy (p=0.0019). 9 (32.1%) developed at the same precursor site, with 6 (77.7%) on the ventro-lateral tongue and floor of mouth. 3 (10.7%) were micro-invasive, 9 patients (32.1%) died from metastatic disease and 12 (42.9%) were disease free (p<0.001).

Conclusion

Squamous carcinoma may arise at the site of a precursor lesion as transformation or new-site development via field cancerisation. Whilst interventional surgery facilitates early diagnosis and treatment of occult disease, thus reducing risk from same-site transformation, new-site cancer is a significant long-term risk for potentially malignant disorder patients.

This article is protected by copyright. All rights reserved.

http://ift.tt/2xfDok5