Oral carcinoma cuniculatum, an unacquainted variant of oral squamous cell carcinoma: A systematic review

Abstract

PurposeOral carcinoma cuniculatum is a rare well-differentiated variant of oral squamous cell carcinoma. The purpose was to systematically review its unique features to differentiate it from other variants as verrucous carcinoma, papillary squamous cell carcinoma and well-differentiated squamous cell carcinoma.Materials and MethodsA systematic review was performed using MEDLINE, Dentistry and Oral Sciences Source and PubMed databases and any existing articles related to the research subject missed in the search strategy to screen ones reporting cases occurring exclusively in the oral cavity in English literature. Variables analyzed included clinical, etiologic, imaging, histopatholgical features, treatment, follow-up and survival rates.ResultsFrom 229 hits, 17 articles with 43 cases were included in the systematic review. Clinically it showed a female predilection with pain and/or ulceration of a relatively long duration and exudation being the most common symptoms. Histologically, it showed more endophytic features comprising well-differentiated squamous epithelium with absent or minimal cytological atypia and multiple keratin filled crypts or cuniculus. Inflammatory stromal reaction and discharging abscesses were reported in most of the cases. Bone destruction was predominant in most imaging features. Complete surgical resection with a safety margin was the treatment of choice in most of the cases with few recorded recurrence cases.ConclusionApprehensive knowledge of oral carcinoma cuniculatum unique features is essential to avoid its misdiagnosis and provide proper treatment especially for recurrent cases.

Cystic Squamous Cell Carcinomas of the Jaws: Twelve Cases Highlighting Histopathological Pitfalls

“…By contrast, CCu are well documented and are probably one of the “family” of papilloverrucous dysplasias and carcinomas that affect the oral cavity, albeit one with specific histopathological features. Patients with CCu are usually aged >60 years, but the mean age in the present series is higher than that reported in a recent review, 2 which also found a slight female preponderance (55.8%). There are 2 reported instances of CCu in children younger than 10 years.…”

“…The vast majority of the other reported cases suggest that the jaws, and particularly the mandibular alveolus, is the most common site of oral CCu. While local destruction is a common feature, metastasis is unusual, and as 3 of the 4 metastases stated to have occurred by Farag et al 2 were reported by Sun et al, 5 this figure is also unreliable. The etiology is uncertain; >30% of patients are tobacco smokers or heavy consumers of alcohol, or both.…”

“…Other than the 4 cases in this report, which we were satisfied met the histological requirements for CCu, we considered the diagnosis in 5 others but decided, on review, the features were not “pure” enough. Farag et al 2 cite at least one case report 10 in which the histological evidence for CCu is dubious. Although bona fide cases of CCu affecting the tongue have been reported, 11,12 in the series of 15 oral CCu described by Sun and coworkers 5 (and included in the review by Farag and coworkers 2 ), there are, suspiciously, 8 lingual examples and the one illustrated is entirely exophytic with no apparent burrowing, endophytic component.…”

“…The etiology is uncertain; >30% of patients are tobacco smokers or heavy consumers of alcohol, or both. 2 Human papilloma virus would appear to have no role. 11,12…”

“…The crypts contain a mixture of keratin and microabscesses. A recent review 2 identified only 43 previously reported cases of oral CCu, even though CCu was first described (in the foot) by Aird and coworkers 3 >65 years ago. The epithet “cuniculate” was coined because of the resemblance of the crypts to a rabbit warren.…”