Expression of stem cell biomarker CD44 in oral squamous cell carcinoma and its association with lymph node metastasis and TNM staging.

Background: Oral squamous cell carcinoma (OSCC) is one of the most prevalent cancers in the world. OSCC is a highly invasive lesion frequently having soaring morbidity as well as substantial mortality, attributed to resistance to therapy, metastasis, and recurrence driven by specific populations of cancer stem cells (CSC). The evidence of the association of expression of stem cell biomarker CD44 and metastatic potential of the tumor is inconclusive in OSCC and hence needs further evaluation.

Objectives: To determine the immunohistochemical expression of CD44 in OSCC and to find its association with lymph node metastasis and TNM staging.

Materials and methods: One hundred and five histologically proven cases of OSCC were studied. Histopathological parameters like depth of invasion, presence of lymph node metastasis, grading, and TNM staging were done according to the new AJCC staging criteria. Both intensity and proportion of CD44 expression were recorded.

Results: The mean age observed in this study was 52.59 years with a male: female ratio of 1:3.76. Forty-nine cases (46.6%) showed a depth of invasion of more than 10 mm. Fifty-two out of one hundred and five cases (49%) had nodal involvement. TNM staging was 5.7%, 7.6%, 44.7%, and 42% for stages I, II, III, and IV, respectively. The majority of the cases (87.5%) showed CD44 expression in the tumor. There was a significant association between the CD44 expression and lymph node metastases (P < 0.001). Higher CD44 expression was seen in stages III and IV (P < 0.001).

Conclusion: CD44, a stem cell biomarker is significantly associated with higher TNM stage and lymph node metastases. This may be useful in predicting the tumor behavior in the small biopsy.