Carcinoma of the tongue in two siblings

Squamous cell carcinoma of the lower lip: exact location match in siblings

BACKGROUND

In recent years, genetic contribution to the development of skin cancers is under the magnifying glass of several authors and is now regarded as the main initial etiology in carcinogenesis.

OBJECTIVE

Two siblings who had squamous cell carcinoma of the lower lip showing an exact location match are presented.

PATIENTS

They did not share common environmental factors, and there was no history of tobacco and/or alcohol abuse.

CONCLUSIONS

It would be scientifically deceptive to draw generous conclusions for the cases here, other than being a very interesting and unusual coincidence, because further evaluation could not be done to scientifically prove a possible genetic contribution.

A review of inherited cancer syndromes and their relevance to oral squamous cell carcinoma

This paper examines the genetic defects associated with inherited cancer syndromes and their relevance to oral cancer. Tumour suppressor genes are now thought of as either gatekeepers or caretakers according to whether they control cell growth directly by inhibiting cell proliferation and/or promoting cell death (gatekeepers) or whether they maintain the integrity of the genome by DNA repair mechanisms (caretakers). In disorders such as xeroderma pigmentosum, ataxia telangiectasia, Bloom syndrome and Fanconi's anaemia, where there are defective caretaker genes, there is an increased incidence of second primary malignancies, including oral cancer. By contrast, with the exception of Li Fraumeni syndrome, abnormalities of gatekeeper genes do not predispose to oral cancer. Not only do Li Fraumeni patients develop second primary malignancies, but defects of the p53 pathway (p53 mutation, MDM2 over-expression, CDKN2A deletion) appear to be a ubiquitous feature of sporadic oral cancer as it occurs in the West. The findings suggest that genetic instability is of fundamental importance in the pathogenesis of oral cancer.