Microinvasive oral squamous cell carcinoma- A clinicopathological study

Abstract

Abstract:Background and objectives: Microinvasive oral squamous cell carcinoma is an early stage malignancy characterized by invasion of superficial lamina propria without invasion of deeper structures. These lesions have a varied clinical presentation, minimal lymphatic involvement and a better prognosis. However, there is no clear consensus on its diagnosis and subsequent management. The aim of this study is to assess the depth of invasion of confirmed cases of microinvasive oral squamous cell carcinoma using special stains and immunohistochemistry with clinical correlation of these lesions.Method: Tissue specimen of clinically diagnosed cases of oral leukoplakia (n=90), oral submucous fibrosis (n=60) and oral carcinoma (n=50) were microscopically evaluated for the presence of microinvasion by two independent examiners. The next step involved confirming the basement membrane breach by using Periodic acid Schiff (PAS) stain for evaluating the integrity of basement membrane. The confirmed cases were assessed using special stain and immunohistochemistry to measure the depth of invasion and were further correlated with the clinical features.Results: A total of 29 cases were confirmed as microinvasive OSCC. These included clinically diagnosed 11 cases of leukoplakia, 7 cases of OSMF and 11 cases of carcinoma. Median age at diagnosis was 46 yrs; males (69%) were more affected than females (31%). The predominant risk factor was tobacco chewing alone (31.03%) which was in the form of gutkha and arecanut; common site was buccal mucosa (76%); predominant clinical presentation was a patch; and histopathology revealed varying grades of epithelial dysplasia. The mean depth of invasion was 31.29 µm (0.03 mm) with the range being 16.91 -66.6 µm (0.02 -0.07 mm). Conclusion:The study suggest that depth of invasion could be a reliable marker to assess microinvasion and that severity of epithelial dysplasia is not a pre-requisite for microinvasive carcinoma.

Insights into incipient oral squamous cell carcinoma: A comprehensive South-American study

“…Observational studies assessing early OSCC have been performed with different histopathological populations, such as microinvasive carcinoma (13,22,37,38) or T1-T2 cases (39,40). Most of our OSCCi sample is composed of cases diagnosed as severe oral epithelial dysplasia/in-situ carcinoma (70.1%).…”

“…High risk of malignant transformation in severe or high-grade oral epithelial dysplasia has been documented to be as high as 57.9% (11,12), making it exceptionally relevant for primary cancer prevention. In this context, severe oral dysplastic lesions exhibiting foci of epithelial cells in ltrating the super cial layer of underlying connective tissue have been described as oral microinvasive OSCC (OSCCmi) (13,14), therefore representing the earliest form of malignant cell dissemination beyond the epithelium. However, achieving diagnostic accuracy in the histopathological assessment of both microinvasion and severe oral dysplasia (formerly referred to as in-situ OSCC (1)) involves several challenges (15).…”

Histopathological Parameters Reported in Microinvasive Oral Squamous Cell Carcinoma: A Systematic Review

“…Due to incompatibility with the predefined criteria, 268 reports were disqualified. Finally, a total of 4 studies were included (4,6,11,12).…”

“…This suggests early diagnosis of incipient OSCC as a must to reduce mortality and comorbidities associated with this disease. Microinvasive oral squamous cell carcinoma (OSCCmi) is an early-stage form of OSCC (4). While frankly invasive OSCC tends to be a straightforward diagnosis, there is scarce literature regarding objective definitive criteria for microinvasive squamous cell carcinoma of the oral cavity in contrast to the same entity arising in other localizations of the body (4), such as cervix (5).…”

Comparative analysis of oral epithelial malignancies using routine stain and modified Cajal’s trichrome stain: An histopathological study

“…Together, these lesions are categorized as disorders that could be cancerous. 1 These lesions require histopathological examination for confirmation of diagnosis and progression to malignancy because their clinical appearance can range from benign to sinister. The histopathological examination of the affected tissue determines the final diagnosis of a clinically suspicious malignancy.…”