Exercises in Oral pathology - Q and A
Question
A 63 year old male was clinically diagnosed with verrucous leukoplakia. A biopsy was done and the histopathology report was as follows:
“The H & E stained section shows hyperkeratotic parakeratinized hyperplastic stratified squamous epithelium with exophytic projections, overlying a densely inflamed stroma. The epithelium shows clefts with keratin plugging in several areas and broad bulbous rete ridges with an endophytic growth pattern. The connective tissue shows dense inflammation with focal areas of nests and islands of dysplastic epithelial cells.”
What could be the final diagnosis based on the report?
💡Scroll down👇 for the answer if you get stuck!
📚Study resources on HackDentistry!
Answer👇
Dissecting clinical and histopathology features
The question does not have clinical clues, besides the fact that it states that the patient was diagnosed with Verrucous Carcinoma.
Histopathology features:
Hyperkeratotic, hyperplastic squamous epithelium with "Exophytic projections"
Epithelium shows clefts with "keratin plugging"
Broad bulbous rete ridges
Endophytic growth pattern of ridges
Connective tissue shows - focal nests and islands of dysplastic epithelial cells.
If you carefully note, the first 4 histopathology features we dissected - diagnosis clearly points towards Verrucous carcinoma (VC). These are classic features of the lesion.
💡What to look for
However, note the last line of the report which says “The connective tissue shows focal areas of nests and islands of dysplastic epithelial cells”.
Verrucous carcinoma (VC) does not show invasion of epithelial cells into the connective tissue unlike squamous cell carcinoma.
VC has an intact basement membrane and shows endophytic growth pattern.
Final diagnosis
Squamous cell carcinoma
💡Note
In fact, it is important for pathologists to screen the lesion thoroughly, to check for foci of conventional squamous cell carcinomas within a verrucous carcinoma.
Foci of invading dysplastic epithelial islands in the connective tissue should raise a red flag and such lesions should be diagnosed and treated as conventional squamous cell carcinomas.
📚Here are some resources for further reading
Donald PM, Renjith G, Arora A. Tobacco Pouch Keratosis in a young individual: A brief description. J Indian Soc Periodontol. 2017;21(3):249–251.
Neville BW, Damm DD, Allen CM, Chi A. Oral and Maxillofacial Pathology. South Asian ed. Elsevier; 2016.
Rajendran R, Sivapathasundaram B. Shafer’s Textbook of Oral Pathology. 7th ed. Elsevier; 2012.
Regezzi JA, Sciubba JJ, Jordan RCK. Oral Pathology: Clinical Pathologic Correlations. 5 th ed. Elsevier; 2007.
The breakdown of histopathological clues and their diagnostic implications is incredibly helpful—especially the emphasis on identifying invasive foci within verrucous lesions. A great reminder of how crucial detailed microscopic analysis is in distinguishing between VC and squamous cell carcinoma.