Santam Chakraborty

Quad shot: A short but effective schedule for palliative radiation for head and neck carcinoma

Background: To evaluate a 2-day course of palliative radiation in patients diagnosed to have inoperable or metastatic head and neck carcinoma. Aim: To evaluate the symptom relief and quality of life in these patients after this short course of radiation. Settings and Design: A pilot study was conducted in a tertiary care institute in India. Materials and Methods: Fifteen patients with stage IV B/C disease, KPS 50-70, were inducted after informed consent. External radiation was given in 2 days, two fractions per day, 6 h apart to a total dose of 14 Gy. Washington University quality of life questionnaire (QOL) was used for assessing QOL before and after radiation. Patients who had more than 50% regression of disease received a second course of similar radiation. All patients were followed up for a mean duration of 6 months. Statistical Analysis: The Wilcoxon signed rank test was used to evaluate the difference between the QOL scores before and after treatment. Results and Conclusions: Out of these 15 patients, majority (13) were males and the mean age of the patients was 62 years. After the first course, all patients had good symptom relief, improvement in the QOL, and 13 out of 15 had more than 50% objective response. The short duration of the treatment was favored by the outstation patients and their attendants. It may be concluded that this short course of radiation is an effective tool for palliative radiation and merits a larger randomized trial.

Dosimetric risk estimates of radiation- induced malignancies after intensity modulated radiotherapy

CONTEXT The increasing popularity of intensity-modulated radiotherapy (IMRT) stems from its ability to generate a more conformal plan than hitherto possible with conventional planning. As a result, IMRT is in widespread use across diverse indications. However, the inherent nature of IMRT delivery makes it monitor unit inefficient and leads to increased normal tissue integral dose. This in turn may result in an increased risk of radiation-induced second malignancies. AIM To calculate the risk of second malignancy post-IMRT. SETTINGS AND DESIGN Observational study in a tertiary care institute. MATERIALS AND METHODS Eighteen previously untreated patients with head and neck cancers (n = 10) and prostate cancer (n = 8) were selected. In these patients, selected infield organs around the planning target volume were contoured, viz. brain and thyroid in patients with head and neck cancer and bladder, rectum and small intestine in patients with carcinoma prostate. The estimates of radiation-induced malignancies in these organs and the whole of the body were derived using the concept of Organ Equivalent Dose. STATISTICAL ANALYSIS USED Descriptive statistics (SPSS version 12). RESULTS The modal estimated incidence of radiation-induced malignancies was 129.87, 1.4, 0.10, 3.42, 7.789 and 129.85 per 10,000 person-years for the brain, thyroid, bladder, rectum, small intestine and whole body respectively. CONCLUSIONS The estimated risk of radiation-induced malignancies in the thyroid and rectum was similar to the available literature, while the risk for bladder carcinomas was lower than that reported. However, the calculated risk of radiation-induced tumors of the brain was more than that reported with conventional radiation therapy. We propose that estimation of the risk of radiation-induced malignancies should be a part of the plan evaluation process and special care should be taken before using this modality in young patients with benign tumors in the head and neck region.

Bladder-rectum spacer balloon in high-dose-rate brachytherapy in cervix carcinoma.

PURPOSE To compare bladder and rectum doses with the use of a bladder-rectum spacer balloon (BRSB) versus standard gauze packing in the same patient receiving 2 high-dose-rate intracavitary brachytherapy fractions. METHODS AND MATERIALS This was a randomized study to compare the reduction in bladder and rectum doses with the use of a BRSB compared with standard gauze packing in patients with carcinoma of the cervix being treated with high-dose-rate intracavitary brachytherapy. The patients were randomized between 2 arms. In arm A, vaginal packing was done with standard gauze packing in the first application, and BRSB was used in the second application. Arm B was the reverse of arm A. The International Commission for Radiation Units and Measurement (ICRU) point doses and doses to 0.1-cm(3), 1-cm(3), 2-cm(3), 5-cm(3), and 10-cm(3) volumes of bladder and rectum were compared. The patients were also subjectively assessed for the ease of application and the time taken for application. Statistical analysis was done using the paired t test. RESULTS A total of 43 patients were enrolled; however, 3 patients had to be excluded because the BRSB could not be inserted owing to unfavorable local anatomy. Thus 40 patients (80 plans) were evaluated. The application was difficult in 3 patients with BRSB, and in 2 patients with BRSB the application time was prolonged. There was no significant difference in bladder doses to 0.1 cm(3), 1 cm(3), 2 cm(3), 5 cm(3), and 10 cm(3) and ICRU bladder point. Statistically significant dose reductions to 0.1-cm(3), 1-cm(3), and 2-cm(3) volumes for rectum were observed with the BRSB. No significant differences in 5-cm(3) and 10-cm(3) volumes and ICRU rectum point were observed. CONCLUSION A statistically significant dose reduction was observed for small high-dose volumes in rectum with the BRSB. The doses to bladder were comparable for BRSB and gauze packing. Transparent balloons of variable sizes are recommended for patients with a less spacious vaginal cavity.

How well do elderly patients with cervical cancer tolerate definitive radiochemotherapy using RapidArc? Results from an institutional audit comparing elderly versus younger patients

Purpose Elderly patients (65 or older) with cervical cancer often receive suboptimal radio-chemotherapy. Intensity-modulated radiotherapy (IMRT) may improve tolerance to treatment in this setting. This study was designed to compare the treatment-related toxicities and compliance with treatment in patients of cervical cancer treated definitively with RapidArc IMRT in our institute. Methods and materials The treatment records of all patients treated with RapidArc IMRT between April 2012 and April 2014 were reviewed, retrospectively. Prospectively collected data regarding treatment toxicity (CTCAE 4.0), treatment outcomes and parameters related to treatment compliance were compared amongst two age groups (< 65 and ≥ 65 years). The results of 66 patients were identified, of whom 23 were found to be ≥ 65 years age. All patients completed planned external beam radiotherapy. However, significantly fewer patients in the elderly group received concurrent chemoradiation (98% versus 65%, p < 0.001). Old age (median 75 years, IQR: 74–78 years) was the commonest cause for non-receipt of chemotherapy. Incidence of grade 3 haematological toxicities (26.7% versus 16.7%) and gastrointestinal toxicity (16.7% versus 13.3%) were not significantly different between the two groups. Other treatment-related toxicities, breaks, treatment duration and early outcomes were also not significantly different between the two age groups. Conclusions The use of IMRT did not result in excess toxicities in the elderly population and was associated with equivalent compliance to treatment. Concurrent chemoradiation can be safely combined in elderly patients with perfect organ function and performance status.

Comparison of intracavitary brachytherapy and stereotactic body radiotherapy dose distribution for cervical cancer: In regard to Cengiz et al.

We have read with interest the comparison by Dr Cengiz et al. (1). In the last decade, technological advancements in tumor imaging, treatment planning, and various forms of high-precision delivery techniques have been dramatic, definitely leading to favorable toxicity profiles (2). Gynecologic brachytherapy has also embraced these new tools for three-dimensional image-guided adaptive implants. The CT imaging for cervical cancer brachytherapy patients lacks soft tissue definition that has been overcome by MRI (3), and point Aebased prescriptions are discouraged (4). The present study used CT-based planning where the current standard is MRI-guided adaptive brachytherapy. The Groupe Europ een de Curieth erapie and the European Society for Radiotherapy and Oncology have spearheaded the research in this area with consistent reporting of excellent improved clinical outcomes (5). As such, the volumes advocated, namely intermediateand high-risk clinical target volumes, cannot be reliably drawn on CT scans without the aid of MRI. Without appropriate target delineation, comparison of plans may be misleading. The authors have pointed out the challenges associated with interstitial brachytherapy; however, these are necessary to obtain proper dose coverage that cannot be achieved with standard intracavitary application in select patients with locally advanced cervical cancer. MRI-guided adaptive brachytherapy can achieve superior dose distributions compared with high-precision external beam techniques (6). Stereotactic body radiotherapy (SBRT) can be a possible solution for patients who are deemed unsuitable for standard brachytherapy (7); however, there is no Level 1 evidence to suggest that SBRT can replace modern adaptive cervical cancer brachytherapy. A more appropriate comparison would have been the comparison of combined intracavitary/interstitial brachytherapy systems with CyberKnife system. Although the authors have highlighted the precision of the CyberKnife stereotactic radiotherapy system in delivering SBRT, the long treatment times required for treatment

Magnitude and Implications of Interfraction Variations in Organ Doses during High Dose Rate Brachytherapy of Cervix Cancer: A CT Based Planning Study

Background. Quantifying the interfraction dose variations in the organs at risk (OAR) in HDR intracavitary brachytherapy (HDR ICBT). Methods. Rectum and bladder were contoured in 44 patients of cervical carcinoma on CT after each fraction of HDR ICBT (9 Gy/2 fractions). Interfraction dose variations (VARact) were calculated. Rigid image registration of consecutive fraction images allowed quantification of the hypothetical variation in dose (VARhypo) arising exclusively due to changes in applicator placement and geometry. VARhypo was regressed against the VARact to find out to what extent the applicator variation could explain the VARact in the OAR. The rest of the variation was assumed to be due to organ deformation. Results. The VARact in the dose to 2 cc of bladder and rectum were 1.46 and 1.16 Gy, respectively. Increased dose was seen in 16 and 23 patients in the subsequent fraction for bladder and rectum, respectively. Doses to OAR would have exceeded constraints in 16% patients if second fraction was not imaged. VARhypo explained 19% and 47% of the VARact observed for the bladder and rectum respectively. Conclusions. Significant interfraction variations in OAR doses can occur in HDR ICBT. Organ deformations are mostly responsible for this variation.

Shielding in whole brain irradiation in the multileaf collimator era: Dosimetric evaluation of coverage using SFOP guidelines against in-house guidelines

AIM Compare the planning target volume (PTV) coverage in three different shielding techniques in cranial irradiation. SETTINGS AND DESIGN Tertiary care center, prospective study. MATERIALS AND METHODS The whole brain and meninges were contoured in ten planning CT scans, and expanded by 5 mm for the PTV. Shielding was designed using the French Society of Pediatric Oncology (SFOP) guidelines (SFOP plan), in-house recommendation (with 1 cm margin from the orbital roof and sphenoid wing) on a igitally Reconstructed Radiograph (DRR) and a third plan was generated using a 3D conformal radiation technique (3DCRT). The coverage of the PTV was noted using the isodose covering 95% of the PTV(D95), minimum dose within the PTV(D min ), and maximum dose within the PTV(D max ). The location of PTV not covered by the 95% isodose curve was noted. The median dose and maximum dose (D max ) to both eyes and maximum dose D max for the lens were noted. STATISTICAL ANALYSIS General linear model method repeated the measure of analysis of variance test (ANOVA). RESULTS PTV coverage was significantly poorer in the SFOP and in-house plans as compared to 3DCRT plan (P=0.04). Median volume of PTV not covered by 95% isodose curve was 4.18 cc, 1.01 cc, and 0 cc in SFOP, in-house, and 3DCRT plan, respectively. CONCLUSIONS In the absence of volumetric planning techniques, SFOP guidelines lead to inadequate coverage and the in-house method is recommended.

Preliminary results of SIB-IMRT in head and neck cancers: Report from a regional cancer center in northern India

BACKGROUND Intensity-modulated radiotherapy using simultaneous integrated boost (SIB-IMRT) is an attractive method for the treatment of head and neck cancers with sparing of the salivary function. AIMS To assess the feasibility, toxicity, and tumor control using SIB-IMRT in locally advanced head and neck cancers in the Indian setting. SETTINGS AND DESIGN The study was conducted in a regional cancer center in northern India. A review of the treatment result of the first 20 patients is presented. METHODS AND MATERIALS SIB-IMRT was planned for 20 patients--14 patients were treated with the SIB-72 schedule delivering a dose of 72 Gy, 66 Gy, and 57 Gy to the PTV GTV , PTV CTV1 , and PTV CTV2 in 33 fractions. Six patients were treated with the SIB-66 schedule delivering 66 Gy, 60 Gy, and 54 Gy to the above-mentioned volumes in 30 fractions. Patients were monitored for toxicity using the CTCAE v 3.0 criteria. Descriptive analysis of toxicity and actuarial estimates of the loco-regional control and survival are presented. RESULTS Grade III mucositis was seen in 65% patients. None of the patients had Grade III dermatitis. The projected 2-year overall survival was 95%. CONCLUSION SIB-IMRT schedules evaluated were found to be safe and effective and are being subjected to further prospective studies.

Acute Toxicities Experienced during Simultaneous Integrated Boost Intensity-modulated Radiotherapy in Head and Neck Cancers — Experience from a North Indian Regional Cancer Centre

AIM A prospective study was conducted to assess the feasibility of simultaneous integrated boost intensity-modulated radiotherapy (SIB IMRT) in our setting. Acute toxicities encountered during and immediately after treatment are reported. MATERIALS AND METHODS Acute toxicity data prospectively collected during the treatment of the evaluable 28 patients with two SIB IMRT schedules were analysed. Toxicity was graded using the Common Terminology Criteria for Adverse Events version 3.0 system. Twenty-one patients were treated with the SIB72 schedule, delivering 72, 66 and 57 Gy in 33 fractions to the gross tumour volume, the high-risk clinical target volume and the low-risk clinical target volume, respectively, whereas seven patients were treated with the SIB66 schedule, delivering 66, 60 and 54 Gy in 30 fractions to the above volumes. No chemotherapy was given during the course of treatment. Descriptive analysis of the incidence and actuarial analysis of the duration of toxicities are presented. RESULTS Grade 3 or greater acute mucosal and actinic toxicity were seen 42.9 and 14.3% of the patients, respectively. Mucosal toxicity appeared by the second week in most patients. Atypical patterns of mucositis were encountered, including one patient with prolonged grade 4 mucosal ulceration in the SIB72 schedule. Grade 3 weight loss was seen in 10.57% of patients. Grade 3 pain was seen in 70% and grade 3 dysphagia in 10% during treatment. CONCLUSION SIB IMRT as used in this study was feasible, although associated with increased rates of mucosal and dermal toxicity.

An audit of the results of a triplet metronomic chemotherapy regimen incorporating a tyrosine kinase inhibitor in recurrent/metastatic head and neck cancers patients

Background: Addition of erlotinib to metronomic chemotherapy (MCT) may lead to further improvement in progression-free survival (PFS) and overall survival in head and neck cancers. The aim of this study was to study the PFS with MCT + erlotinib combination in our setting. Methods: A single-arm prospective observational study conducted at Malabar Cancer Center. Patients warranting palliative chemotherapy for head and neck cancers, having adequate organ function, not-affording cetuximab and not willing for intravenous chemotherapy were included in this study. Oral methotrexate (15 mg/m 2 /week), oral celecoxib (200 mg twice daily), and erlotinib (150 mg once daily) were administered till the progression of the disease or till intolerable side-effects. Patients underwent toxicity (CTCAE version 4.02) and response (RECIST version 1.1) assessment every 30 days. Statistical analysis was performed using SPSS version 16 (IBM, New York, USA). Descriptive statistics and Kaplan-Meier analysis have been performed. Results: A total of 15 patients received MCT. The median age of these patients was 65 years (range: 48-80). The Eastern Cooperative Oncology Group Performance Status was 0-1 in seven patients (46.7%), while it was 2 in eight patients (53.3%). The primary sites of tumor were predominantly oral cavity, 11 (73.4%). Prior to MCT, treatment with palliative radiation therapy was given in 11 patients and curative treatment in two patients. The best response post-MCT was complete remission in two patients, partial remission in seven patients, stable disease in four patients, and progressive disease in two patients. The median estimated PFS was 148 days (95% confidence interval 95.47-200.52 days). For a median follow-up of 181 days, there were only three deaths. Grade 3-4 toxicity was seen in six patients (40%). Dose reduction was required in four patients (26.7%). Conclusion: The addition of erlotinib to an MCT schedule of methotrexate and celecoxib resulted in a promising PFS and should be tested in future studies.