Effectiveness of Normal Saline Irrigation in Reducing Wound Contamination during Oral Cancer Surgery: A Cytological Analysis.

Background: Tumour manipulation during surgery can lead to the dissemination of malignant cells and potential wound contamination. Despite the widespread practice of irrigating surgical sites with normal saline, the efficacy of this measure in reducing epithelial contamination in oral cancer surgery remains unclear.

Objectives: This study aimed to assess the proportion of normal saline wash effluents contaminated by epithelial cells or debris during oral cavity cancer surgery, and to evaluate the effectiveness of saline irrigation in reducing contamination.

Methods: A total of 132 patients with biopsy-proven, treatment-naïve squamous cell carcinoma of the oral cavity undergoing surgery were included. Wash effluents from the tumour bed and neck incisions were collected post-irrigation with normal saline and analysed using cell block cytology. Cytology smears from the tumour bed and incision edges were examined for cellular contaminants. Data were analysed using Chi-square tests and Mann-Whitney tests.

Results: Epithelial or abnormal epithelial cells were detected in 24% of cell block samples, while 21% showed cellular debris. Following normal saline irrigation, the positivity rate for epithelial cells or debris in smears decreased from 55% to 7.6%, a statistically significant reduction (p < 0.001). Perineural invasion was significantly associated with the presence of exfoliated cells (p = 0.037).

Conclusions: Irrigation with normal saline significantly reduces the presence of exfoliated epithelial cells and cellular debris in wound sites during oral cancer surgery. The results support the continued use of mechanical cleansing measures during surgery to minimize the risk of tumour cell implantation.