Introduction
Squamous cell carcinomas (SCC) represent more than 90% of the upper
aerodigestive tract cancers and can affect the mucosa of the oral
cavity, pharynx and larynx. Worldwide, they represent the
8th most common cancer and even rank
2nd when the risk factors tobacco and alcohol are
simultaneously present [1]. It has been reported that these cancers
are 15 times more frequent when tobacco and alcohol are consumed
synergistically [2]. Indeed, the alcohol-smoking patient, in his
6th decade of age with a low socio-economic lifestyle,
is considered to be the most frequent patient profile of SCC in the
upper aerodigestive tract, and more specifically the oral SCC [1].
However, recently, two other population profiles are emerging for the
oral SCC, with an increasing trend in elderly women, possibly linked
with denture trauma and toxic exposure [3] and a tendency of
increasing tongue cancers in young white women [4] [5]. While
HPV infection was associated with the increasing incidence of
oropharyngeal cancers in nonsmoker young patients, no evident
association with oral and tongue cancer in young women has been found.
Tobacco and alcohol consumption seem to have a limited link with these
two patient profiles [6] [3]. Other risk factors, such as
cannabis consumption, environmental factors, dietary factors, body mass
index, dental hygiene, immunosuppression, genetic and familial factors,
viral infection, and co-morbidities have been suggested [7]. Some
inflammatory diseases and potentially malignant disorders are also
likely to degenerate and may be linked to the increased incidence of
SCC. Among these, lichen planus is reported.
Lichen planus (LP) is a chronic muco-cutaneous inflammatory disease
which can affect the skin and appendages, but more frequently the
mucosal membranes and more specifically the oral mucosa. Oral lichen
planus (OLP) affects 1 to 2% of the population with a slightly higher
prevalence in women (60 to 65%) [8] [9]. The average age of
onset is between 30 and 60 years of age. Clinical and histological
diagnosis criteria of OLP has been well defined and updated in a recent
report published by a group of experts in a workshop organized by the
collaborating center of the World Health Organization (WHO) for oral
cancer in the UK. These criteria, mainly based on clinical
characteristics, are summarized in table 1 [10].
OLP is often discovered during a routine consultation and progresses in
flare-ups, with phases of remission and exacerbation. The lesion is
preferentially located on the cheek mucosa and at the lower vestibular
side, but is also detected on the dorsal surface and lateral edges of
the tongue, as well as on the attached gingiva [11]. After several
years of evolution, OLP is characterized by mucosal atrophy and
fibrosis. The physiopathology of OLP is still not elucidated and relies
on immunological hypotheses, and may be associated with some autoimmune
pathologies like chronic hepatitis, myasthenia gravis, ulcerative
colitis [11].
Since several clinical studies have shown that OLP has an increased risk
of malignant transformation, the WHO has classified this entity among
“Oral Potentially Malignant Disorders” [10]. Potentially malignant
lesions are a morphological alteration of the tissue in which cancer has
a greater chance of occurring than in tissue without apparent
modification [12]. Even though the incidence and the risk of OLP to
evolve into cancer has been widely discussed, controversies exist
between authors [13] [14] [15]. The difficulty is to
understand whether OLP has an intrinsic potential for malignant
transformation and whether this is accentuated by other factors.
Although rare, some cases of tongue cancer in pregnant women have been
previously reported, but not arising from a potentially malignant
disorder : [16] [17] [18]. Among signaling pathways involved
in tumor development, pregnancy induces physiological changes that may
promote neoplastic growth, such as changes in vascular networks,
elevated metabolism, increased circulating growth factors, and hormonal
responses, which may be amplified mediated by estrogen and progesterone
receptors [19].
Hereafter, we report a rare case of a young pregnant patient presenting
a tongue SCC diagnosed concomitantly with an OLP.