ABSTRACT
OBJECTIVES: To study the utility of fluorodeoxyglucose (FDG) positron emission tomography (PET) in predicting (1) the World Health Organization (WHO) histologic type and differentiating low‑risk from high‑risk types. (2) Tumor stage and differentiate early from advanced stage disease. MATERIALS AND METHODS: Patients with thymic epithelial neoplasia who underwent a pretreatment FDG‑PET study were included. Tumor maximum standardized uptake value (SUVmax) was correlated with the WHO histologic type and also with the Masaoka‑Koga (MK) staging system. Patients with WHO Type A, AB, and B1 were classified as low risk and those with B2 and B3 as high risk. Thymic carcinomas belonged to Type C. Patients with MK Stage I and II disease were grouped as early stage and those with Stage III and IV as an advanced stage. Differences in SUVmax between the various groups were calculated. RESULTS: The SUVmax of thymic carcinomas was significantly higher as compared to low‑risk (P = 0.001) and high‑risk groups (P = 0.007). The SUVmax of high‑risk group was also significantly higher than the low‑risk group (P = 0.002). SUVmax cutoff of 6.5 was able to differentiate thymic carcinomas from thymomas with 100% sensitivity and 87.2% specificity. The SUVmax in patients with advanced stage disease showed a higher trend compared to those with early stage, but the difference was not significant (P = 0.167). CONCLUSION: PET can differentiate thymic carcinomas from rest of the thymoma subtypes by the virtue of their higher FDG uptake. It can also provide valuable information in differentiating high‑risk from low‑risk thymomas and in predicting disease stage.
ABSTRACT
Objective: The objective of the following study is to investigate the efficacy and impact of induction chemotherapy in T4b oral cavity cancers. Materials and Methods: It's a retrospective analysis of prospectively collected data of T4b oral cavity cancer patients who were offered induction chemotherapy and then assessed for resectability at the end of 2 cycles of chemotherapy. Post-induction these patients either underwent surgical or non-surgical local intervention depending upon their response. These patients were then followed-up until either recurrence progression or death whichever was later. Statistical analysis was performed by SPSS version 16. Descriptive analysis was performed. Factors affecting achievement of resectability were sought by univariate and multivariate analysis. The impact of surgery on overall survival (OS) was studied using Kaplan Meier survival analysis with the use of log rank test. Results: A total of 110 patients received chemotherapy. Median age been 41.5 years (range 25-66 years). 21 (20%) of our patient received 3 drug regimen while the rest of our patients received 2 drug regimen. Partial response was achieved in 28 patients, stable disease in 49 patients and progression was noted in 23 patients. Resectability was achieved in 34 (30.9%) of 110 patients. The estimated median OS in patients who underwent surgery was 18.0 months (95% confidence interval [CI]: 13.6-22.46 months) and for those treated with non-surgical treatment was 6.5 months (95% CI: 5.6-7.4 months) (P = 0.0001). Conclusion: Use of induction chemotherapy is safe and can achieve resectability in 30.9% of our T4b patients. In those patients undergoing resection have much better OS then those who underwent non-surgical local treatment.