Significance of expression of tumor-associated microRNA-21 and -375 for predicting the course of cancer of oral cavity.

AIM: To investigate the features of expression of miRNA-21 and miRNA-375 in tumor cells of patients with cancer of oral cavity (COC) and to determine the possibility of their use to predict the aggressiveness of COC course. MATERIALS AND METHODS: The work is based on the results of examination and treatment of 50 patients with stage II-IV COC. miRNA expression in tumor cells was analyzed by real time reverse transcription polymerase chain reaction. RESULTS: High levels of miRNA-21 expression (> 0.26 a.u.) and miRNA-375 (> 0.36 a.u.) were determined in 72.0% and 63.0% of cases. We revealed a tendency to decreased miRNA-21 expression and increased miRNA-375 expression in tumors of patients with recurrence-free survival less than 12 months and the presence of metastatic lesions in regional lymph nodes. In patients with COC of low differentiation grade, the level of miRNA-21 was 2.0 times lower compared with tumors of moderate differentiation grade (p < 0.05), while the expression of miRNA-375, on the contrary, was higher in tumors of low differentiation grade. A decreased expression of miRNA-21 (< 0.26 a.u.) against the background of decreased levels of miRNA-375 (< 0.36 a.u.) in tumor cells was associated with worse recurrence-free survival. CONCLUSIONS: The obtained results indicate the relation between the main clinical and pathological characteristics of patients with COC and the levels of miRNA-21 and -375 expression in tumor tissue, which indicates the involvement of these miRNAs in the formation of COC malignancy evidencing on their potential usefulness as additional prognostic markers.

Comparative analysis of the efficacy of definitive chemoradiation therapy and surgery followed by adjuvant radiation therapy in advanced-stage oral tongue cancer.

The aim of the study was to compare the efficacy of definitive chemoradiation therapy (CRT) and primary surgery followed by adjuvant radiotherapy (RT) or CRT in the management of patients with stage III-IVA-B resectable oral tongue squamous cell carcinoma (OTSCC). MATERIALS AND METHODS: It is a retrospective analysis of the treatment outcomes of 211 patients with stage III-IVA-B resectable OTSCC. The patients were divided into two groups depending on the treatment modality: 114 patients received surgery followed by adjuvant RT or CRT (S-RT/CRT) group; the definitive CRT group consisted of 97 patients. RESULTS: The five-year overall survival (OS) was 57.0% in S-RT/CRT group vs 20.4% in CRT group; the five-year disease-free survival (DFS) in S-RT/CRT group was 56.5% vs 15.5%, in the CRT group. Comparison of survival curves revealed statistically significant higher OS and DFS rates in patients of S-RT/CRT group as compared with those in CRT patients (hazard ratio = 0.33 (95% confidence interval 0.23-0.47), p < 0.001 vs hazard ratio = 0.25 (95% confidence interval 0.17-0.37), p < 0.001). A multivariate analysis showed a statistically significant prognostic effect of the primary tumor extension cT4 (p = 0.004), cervical lymph node involvement cN2 (p < 0.001), cN3 (p = 0.04) and treatment modality (p < 0.001) on OS. There was also found a statistically significant prognostic effect of the primary tumor extension cT4 (p = 0.02), cervical lymph node involvement cN2 (p < 0.001) and treatment modality (p < 0.001) on DFS. 18 (15.8%) patients of S-RT/CRT group and 13 (13.4%) patients (p = 0.77) of CRT group developed mandibular osteoradionecrosis. CONCLUSION: Primary surgery with adjuvant RT or CRT in advanced-stage resectable OTSCC significantly increases five-year OS and DFS rates as compared to those after definitive CRT.

Clinical and pathological prognostic factors in patients with stage III-IVA-B oral squamous cell carcinoma.

The aim of the work was to study clinical and pathological factors affecting the prognosis of the disease in patients with stage III-IVA-B oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: A retrospective review of medical records of 234 patients with stage III-IVA-B OSCC was performed in order to study the impact of clinical and pathological factors on disease-free survival (DFS) and overall survival (OS). RESULTS: Multivariable analysis of clinical factors revealed a statistically significant effect of stage IVA-B and the presence of surgical complications on DFS (hazard ratio (HR) = 4.9 (95% confidence interval (CI) 2.9-8.3), p < 0.001; HR = 1.6 (95% CI 1.0-2.6), p = 0.047), respectively. Stage IVA-B, the presence of surgical complications and the retromolar trigone subsite were found to have a statistically significant impact on OS (HR = 4.0 (95% CI 2.5-6.5), p < 0.001; HR = 1.8 (95% CI 1.1-2.8), p = 0.01; HR = 1.9 (95% CI 1.1-3.2), p = 0.02), respectively. Multivariable analysis of pathological factors showed a statistically significant effect of positive resection margins, the multiple lymph node involvement and high-grade tumor on DFS (HR = 3.7 (95% CI 2.0-6.6), p < 0.001; HR = 4.3 (95% CI 2.8-6.7), p < 0.001; HR = 1.6 (95% CI 1.1-2.2), p = 0.01), respectively. Besides, positive resection margins and multiple lymph node involvement were found to cause a statistically significant impact on the OS (HR = 3.6 (95% CI 2.0-6.5), p < 0.001; HR = 3.7 (95% CI 2 5-5.6), p < 0.001), respectively. A tumor grade tended to worsen OS (HR = 1.4 (95% CI 1.0-1.9), p = 0.053). CONCLUSION: Stage IVA, B, the presence of surgical complications, the retromolar trigone subsite, positive resection margins, multiple lymph node involvements and high-grade tumor were found to be significant clinical and pathological prognostic factors in patients with stage III-IVA-B OSCC.