Oral Squamous Cell Carcinoma in those 40 Years of Age and Younger: A Single Institute Retrospective Study
An increasing incidence of oral squamous cell carcinoma (SCC) has been noted in younger age groups. These patients often lack the stereotypical risk factors associated with oral SCC in an older age group.1 Human papilloma virus has been hypothesized to be involved in oral SCC in this younger age group but more evidence is needed to definitively prove this. 2
Materials and methods:
A retrospective study evaluating subjects 40 years or less who presented to a single institute between 1992 and 2013. Subjects’ medical records were reviewed and well as operation reports, radiological reports, and pathological reports. Variables included demographics, risk factors, pathological findings, surgical intervention, adjuvant therapy and follow up related factors. Chi-square test and generalized linear mixed models were used for statistical analysis of data.
Results:
Forty four subjects out of a potential of 67 subjects who met the inclusion criteria were included (23 excluded due to incomplete data). Mean age was 33.7 years (SD 5.5 years). The majority of subjects were male (N=25) [56%] and white (N=39) [87%]. Sixty percent were non smokers (N=26) [P<0.001]. The most common sites were tongue [80%], floor of mouth (14%), and other sites (7%) [P<0.001]. Breakdown of pTNM was as follows: Tis-3%, T1–41%, T2-46%, ≥T3-10%, N0-73%, N1-11%, ≥N2-16%. Peripheral nerve invasion and/or lymphovascular invasion was present in 33% of subjects. Extracapsular spread was present in 10% of those with lymphadenopathy. P16 status was reported in 9 subjects with 3 positives. Wide local excision was the primary surgical modality (80%), followed by mandibulotomy/mandibulectomy(9%), subtotal glossectomy(7%) and/or hemiglossectomy(5%). Neck dissection was carried out in 71% of subjects based on T stage, depth of invasion on biopsy and/or the presence of lymphadenopathy. Forty six percent of subjects received a free flap for reconstruction. Adjuvant radiation was administered to 63% of subjects and adjuvant chemotherapy was administered in 33% of subjects. A significant association was found between the need for adjuvant radiation and/or adjuvant chemotherapy and perineural invasion and lymphovascular invasion (P<0.05). Nine subjects had a reported recurrence. Generalized linear modelling demonstrated a significant association between recurrence and the presence of perineural invasion (P=0.0024). No significant association was found between recurrence and T stage(P=0.35), N stage (P=0.76), lympovascular invasion (P=0.92), depth of invasion(P=0.3), or grade(P=0.33).
Conclusion:
The majority of subjects in this study did not have the traditional profile or risk factors associated with oral SCC. No variance in the determination of the aggressiveness of surgical intervention was found compared to the well established determinants used for older subjects with oral SCC. Analysis of the impact of P16 status to oral SCC was not possible in this study due to inadequate reporting. Considering the subjects’ age, factors such as tumor biology may be a possible explanation for the significant association between perineural invasion and recurrence in this study.
References:
[1] Panwar A, Batra R, Lydiatt WM, Ganti AK. Human papilloma virus positive oropharengeal squamous cell carcinoma: A growing epidemic. Cancer Treat Rev 2014;40:215- 219
[1] Miller CS, Johnstone BM. Human papillomavirus as a risk factor for oral squamous cell carcinoma: A meta analysis 1982 – 1997. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2001; 91:622-635