Selected molecular markers as indicators of clinical profile, tumor characteristics and treatment outcome in squamous cell carcinoma of the larynx.

Abstract

e17522 Background: Laryngeal Squamous cell carcinoma is widely prevalent in India and is the fourth leading cancer in males. The possibility that specific tumour characteristics (demonstrable by immunohistochemistry) may aid the clinician in choosing optimal treatments for a specific tumour, holds great promise. Objectives of the present study were to study the expression of select molecular markers p53, Bcl-2 (Apoptotic markers), EGFR, Ki67, Cyclin D1 (Proliferation markers) and Cox-2 (Inflammatory marker) in LSCC so as to form a hypothesis that a particular group of markers will be useful in determining the prognosis of LSCC. Methods: We studied 72 cases of laryngeal squamous cell carcinoma in an attempt to determine relationship between their clinicopathological characteristics and treatment outcome with the six molecular markers. Samples from patients who underwent laryngectomy from Jan 2006 to Dec 2010 were taken and analyzed prospectively and followed up till Dec 2015 or till death. . Immunoreactivity in tissue sections was evaluated as negative when no positive cells were observed within the tumor, weak (1+) , moderate (2+) , and strong or intense (3+) . Data were analyzed using SPSS software package. Chi squared test or exact test were used to test the associations. Logistic regression analysis was used to estimate the odds ratios and 95% confidence intervals. The disease free survival time of each patient was calculated by taking the difference between the date of surgery and the recurrence date/ death date/ the last follow up date whichever is applicable. Results: Proliferation markers EGFR, Cyclin D1 and Ki 67, individually and collectively were predictive of extracapsular spread and perineural spread of tumour. Node negative patients having intense expression of Cyclin D1 or Ki 67 has bad prognosis.. The significant expression of Cox-2 was highly predictive of Node positivity. In older patients and in T4 stage the presence of P53 / Bcl-2 resulted in worse overall survival. Markers of aggressiveness were identified as p53, Bcl-2 Cox-2. Markers of invasiveness were EGFR, Cyclin D1 and Ki 67. Markers predicting survival were p53, BCl-2, Cyclin D1 and Ki 67. Conclusions: If Proliferation markers are detected preoperatively in biopsy specimens, has important implications in planning aggressive management Cyclin D1 or Ki 67 in Node negative patients indicate need for a neck dissection or irradiation. Cox-2 assessment will be useful in predicting the occult nodal metastasis for prophylactic treatment