Résumé
Aim: This study intended to compare the dosimetric parameters using different definitions of prescription point A in high dose rate (HDR) brachytherapy of cervical cancer patients. Background: Manchester point A has been widely used for prescribing dose in brachytherapy. However, due to certain limitations of this point, a new definition of point A has been recommended by the American Brachytherapy Society (ABS). Materials and Methods: We retrospectively investigated 55 computed tomography-based plans of 20 cervical cancer patients treated with Ir-192-based intracavitary HDR brachytherapy. The dose of 7 Gy in 3 fractions each was prescribed to point A using revised Manchester definition of point A (AMAN) and ABS guideline definition (AABS). The effect of both definitions on various parameters including dose to point A and 90% of tumor volume (D90), dose received by 2cc volume of bladder, rectum and small bowel and treatment volume receiving 100% of prescription dose (V100) was analyzed. Results: Mean percentage difference of point AMAN dose and AABS dose with respect to prescription dose was 1.25% ± 1.43% and 1.21% ± 1.01%, respectively. Mean V100 was 80.4 ± 20.45cc and 88.47 ± 16.78cc for AMAN and AABS plans, respectively, while mean percentage difference between prescribed dose and D90 was found to be –37.90% ± 25.06% and –30.47% ± 25.50% respectively for both the definitions. Conclusion: Doses to both Manchester point A and ABS point A may be recorded during the transition period. However, ABS point A can be preferred over the Manchester point A as it conforms better with the desired dosimetric outcome and is found to be more static.
Résumé
Context: Poor survival of the glioblastoma multiforme (GBM) has been attributed in part to the invasive nature of the lesion making complete surgical removal near impossible. Phosphatase of regenerating liver‑3 (PRL‑3), matrix metalloproteinases‑2 and ‑9 (MMP‑2 and MMP‑9), and epidermal growth factor receptor (EGFR‑1) play a role in invasive nature of tumor cells. Aims: This study was conducted to evaluate PRL‑3, MMP‑2, MMP‑9, and EGFR‑1 (markers) expression in cases to GBM and to correlate their expression with therapy response and survival. Settings and Design: GBM cases (n = 62) underwent surgery followed by radiation (n = 34) and chemoradiation (n = 28). Using WHO Response Evaluation Criteria in Solid Tumors criteria response to therapy was assessed at 3 months and cases followed up for survival. Subjects and Methods: Expression of markers was assessed by immunohistochemistry as a percentage of positive tumor cells in hot spots. Statistical Analysis Used: Kaplan–Meier, ANOVA, Chi‑square test, univariate, and multivariate Cox‑regression analysis was done. Results: Response to therapy was evident in 54.8% cases of responders with the mean survival of 494.03 ± 201.13 days and 45.2% cases of non responders (278.32 ± 121.66 days) with P = 0.001. Mean survival for the patient’s opted chemoradiation was 457.43 ± 222.48 days which was approximately 3 months greater than those who opted radiation alone (P = 0.029). We found PRL‑3 overexpression was an independent, significant, poor prognostic factor for survival by multivariate analysis (P = 0.044). Cases negative for MMP’s and EGFR showed increased survival, but the difference was insignificant. Conclusion: PRL‑3 expression appears to be related to an adverse disease outcome.