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The aim of this study was to evaluate the breast dose heterogeneity in CT-based radiotherapy treatment planning and to correlate with breast parameters. Also, the number of slices required for treatment planning in breast cancer by tangential field technique has been assessed by comparing the treatment plans according to International Commission on Radiation Units and Measurement (ICRU) 50 guidelines (1993) for single-slice, three-slice, and multi-slice (3D) planning. Sixty women who underwent isocentric tangential field breast radiotherapy were included in this study. The plans were optimized and analyzed with dose volume histograms. Sixty-three percent of the single-slice plans and 26.7% of the three-slice plans showed poor dose homogeneity as compared to the 3D plans. Dose inhomogeneity correlated better with breast volume (r² = 0.43) than the chest wall separation (r² = 0.37) and breast area product (r² = 0.36). Similarly, breast volume correlated better with breast area product (r² = 0.80) than with chest wall separation (r² = 0.56). Breast volume can be approximated to breast area product from the relation, breast volume = [(breast area product x 8.85) - 120.05]. The results of this study showed that most of the cases require 3D planning for breast cancer. It also showed that patients with large breast are prone to have more dose inhomogeneity with standard tangential field radiotherapy. In centers where 3D planning is not possible due to lack of facilities or workload, three slices-based planning can be performed to approximate the dosimetric advantage of 3D planning. [ABSTRACT FROM AUTHOR]

The author reflects on the importance of radiotherapy for cancer treatment in India. Topics discussed include the installation of the multi-leaf collimator designed by the Bhabha Atomic Research Centre at the Advanced Centre for Treatment, Research and Education in Cancer, under the Tata Memorial Center, the 44 Bhabhatron?II cobalt?60 (Co?60) teletherapy machines named after Indian nuclear scientist, Homi J. Bhabha and the intensity modulated radiotherapy.

The author reflects on technological developments in radiation oncology in India. The intensity modulated radiotherapy (IMRT) can be an effective tool to reduce radiation treatment morbidity. The image guided radiotherapy (IGRT) keeps track of organ motion and has the ability to deliver accurate treatment. The combination of radiofrequency ablation and brachytherapy is being explored as an aid to residual diseases after conventional treatment. He mentions the need to improve physician training.

Aim: Glioblastoma (GBM) is one of the most aggressive neoplasms of the central nervous system with dismal survival. In recent years, different variants of GBM have been described in the literature. GBM with areas of neuroectodermal differentiation (GBM-PNET) is a relatively new entity in GBM. Presence of the neuroectodermal component increases the propensity of systemic dissemination as with other intracranial primitive neuroectodermal tumors (PNET). The optimal treatment for these patients remains a controversy, with authors reporting local radiotherapy to craniospinal irradiation and chemotherapy. We intend to analyze the pattern of care for GBM with neuroectodermal component.Materials and Methods: We retrieved data of four patients with GBM-PNET treated in our institute; data were also retrieved from published series to derive treatment and outcome results.Results: In this series, we report the outcome of a series of four patients of GBM-PNET treated with adjuvant radiotherapy and temozolomide. All but one patient underwent gross total resection of the tumor. Adjuvant hypofractionated radiation with concurrent and adjuvant temozolomide was used in all cases. The median follow-up was 12.9 months in the present series. One patient experienced local recurrence 18 months after the treatment. A review of published literature on GBM-PNET was done; studies with details of patient outcome were used for an independent analysis. Twenty-three patients were identified, and the pooled analysis revealed a median progression free and overall survival of 10 and 25, months respectively. Extent of surgery, local radiation vs. craniospinal irradiation, and age at presentation had no impact on the survival.Conclusion: GBM PNET is a new entity with only few cases reported so far. Clinical behavior and treatment outcome of these tumors are not different from conventional GBM. However, these patients are at higher risk of CSF dissemination. Hence, an individualized treatment approach is best suited. [ABSTRACT FROM AUTHOR]

Context and Aim: The prognosis of primary gliosarcoma (PGS) remains dismal with current treatment modalities. We analyzed the outcome of PGS patients treated with concurrent and adjuvant temozolomide (TMZ).Settings and Design: Retrospective single institutional analysis.Materials and Methods: We retrospectively evaluated 27 patients of PGS treated with radiotherapy (RT) and TMZ during 2007-2012.Statistical Analysis Used: Overall survival (OS) was estimated by the use of Kaplan Meier method and toxicities were evaluate using common terminology criteria for adverse events version 2.0 (National Cancer Institute, USA).Results: Median age at presentation and Karnofsky performance status was 45 years and 90 respectively and male: female ratio was 20:7. Patients received adjuvant RT to a total dose of 60 Gy at 2 Gy/fraction. All patients except 5 received adjuvant TMZ to a median number of 6 cycles. Grade 2 and 3 hematological toxicity was seen in 8% and 4% of patients respectively during concurrent RT. During adjuvant chemotherapy, 13.6% had Grade 3 thrombocytopenia and 9.5% had Grade 3 neutropenia. Median OS was 16.7 months (1 year and 2 year actuarial OS was 70.8% and 32.6% respectively). Adjuvant TMZ was associated with a better survival (median survival 21.21 vs. 11.93 months; P = 0.0046) on univariate analysis and also on multivariate analysis (hazard ratio 1.82, 95% confidence interval: 1.503-25.58; P = 0.012).Conclusions: The results of our study, largest series of patients with PGS treated with concurrent and adjuvant TMZ shows an impressive survival with acceptable toxicity. We suggest TMZ be included in the "standard of care" for this tumor. [ABSTRACT FROM AUTHOR]

Background and Objective: Neurocytoma (NC) is a rare benign neuronal tumor. A complete excision remains curative for most of these tumors, but atypical histology and extra-ventricular location often necessitates adjuvant therapy. We intended to explore the clinico-pathological features and treatment outcome in patients of NC in our institute.Materials and Methods: Medical records were reviewed and data collected on NC over a 6-year period (2006-2012) from the departmental archives. Disease free survival (DFS) was analyzed by Kaplan-Meier method.Results: A total of 18 patients met the study criteria. Fourteen patients had intra-ventricular neurocytoma (IVNC), right lateral ventricle being the most common site of origin. Gross total resection and near total resection were achieved in eight cases each whereas tumor decompression and biopsy could be done in two cases. On post-operative histopathological examination, eight patients were found to have atypical NC while 10 patients had typical NC. All patients underwent adjuvant radiation. The median dose of post-operative radiation was 56 Gy. All patients were alive at their final follow-up. One patient had both clinical and radiological evidence of local relapse. In the evaluable patients (n = 18), after a median follow-up of 35 months the DFS rate at 2 years and 3 years are 100% and 83% respectively.Conclusion: Use of adjuvant radiation to a total dose of 56 Gy enhances the local control and achieves superior survival in patients of NC. Use of 3D conformal planning techniques may help us to achieve better therapeutic ratio in patients with NC. [ABSTRACT FROM AUTHOR]

Background: The significant impact of postoperative radiotherapy (PORT) on cardiac morbidity in patients of early breast cancer (EBC) undergoing breast-conserving surgery has been shown in different studies. The present study was conducted to assess the impact of surgery and the side of involvement on radiation dose to left anterior descending artery (LAD) and Left circumflex coronary artery (LCx).Materials and Methods: Totally, 58 patients of EBC were randomly chosen for this dosimetric study and planned with tangential field technique without intensity modulation (IM). Heart, LAD, and LCx (n = 55) were contoured. Dose volume histograms were analyzed to determine the Dmax (maximum dose) and Dmean (mean dose) of LAD and LCx. Student's t-test was used for comparative analysis of the means.Results: The mean Dmax of LAD for left (L) EBC was 3.17 Gray (Gy) while for right (R) EBC it was 0.86 Gy (P = 0.007; 95% C.I, 1.14-3.48). The mean Dmean of LAD for L-EBC and R-EBC were 1.97 Gy and 0.79 Gy, respectively (P = 0.029; 95% C.I, 0.77-1.60). The mean-Dmax of LCx for patients with L-EBC (2.9 Gy; range: 1.2-4.35 Gy) was statistically higher than that for R-EBC (1.3 Gy; range: 0.7-3.2 Gy) (P = 0.045). The mean-Dmean of LCx for L-EBC (2.1 Gy; range: 0.6-3.6 Gy) was also significantly higher than that of L-EBC (0.9 Gy; range: 0.7-2.1 Gy) (P = 0.03). There was no significant impact of the pattern of surgery on LAD dose, but significance was noted for LCx dose parameters (P = 0.04 and 0.08 for m-Dmax and m-Dmean of LCx).Conclusion: This pilot dosimetric study confirms the assumption that patients with left-sided EBC are at higher risk of developing long-term cardiac morbidity when treated with PORT due to increased dose to LAD. [ABSTRACT FROM AUTHOR]

Medical electron linear accelerators with the capability of generating unflat photon (flattening filter-free, FFF) beams are also available commercially for clinical applications in radiotherapy. However, the beam characteristics evaluation criteria and parameters are not yet available for such photon beams. Atomic Energy Regulatory Board (AERB) of India constituted a Task Group comprising experts from regulatory agency, advisory body/research and technical institutions, and clinical radiotherapy centers in the country to evolve and recommend the acceptance criteria for the flattening filter-free (FFF) photon beams. The Task Group thoroughly reviewed the literature and inputs of the manufactures/suppliers of the FFF linac and recommended a set of dosimetry parameters for evaluating the characteristics of the unflat photon beam. The recommendations included the evaluation of quality index, degree of unflatness, difference in percentage surface dose between flat and unflat photon beams, percentage depth dose at 10 cm depth, off-axis-ratios and radiation beam penumbra. The recommended parameters were evaluated for FFF photon beams generated by three different models of the linac, and it was observed that recommended evaluation methods are simple and easy to be implemented with the existing dosimetry and quality assurance infrastructure of the linac facilities of the radiotherapy departments. Recommendations were also made for periodic quality control check of the unflat photon beams and constancy evaluation in the beam characteristics. [ABSTRACT FROM AUTHOR]

BACKGROUND: Malignant tumors of the trachea are rare. A multimodality treatment approach is often necessary. Outcomes of radical non-surgical approaches are sparse. Radiation combined with sequential or concurrent chemotherapy is an important treatment option. MATERIALS AND METHODS: We present an analysis of outcomes using modern radiotherapy and chemotherapy for tracheal tumors. RESULTS: Radiation dose escalation using modern techniques is of benefit for these tumors. The results with chemotherapy are encouraging. CONCLUSIONS: Radiation plays a distinct role and should be a part of treatment for these tumors. The role of chemotherapy needs to be studied further. [ABSTRACT FROM AUTHOR]

Background: Brainstem gliomas are highly heterogeneous tumors both in their clinical manifestation and in their pathology. Despite significant advances in the surgery for brainstem gliomas many aspects of this pathology are still unclear Objective: To evaluate the clinical, radiological and surgical outcome of 40 focal 'intrinsic' brainstem gliomas and propose a surgical strategy-oriented classification. Materials and Methods: A total of 40 focal 'intrinsic' ("expanding variety") tumors have been operated over a period of 8.5-years (January 1998-June 2007). Our criteria included patients with (1) well-defined gadolinium enhancing tumor; (2) relatively long duration of symptoms (> six months) and (3) good neurological functional status and independent for all activities of daily living. The cutoff size of 2 cm was not rigidly adhered to. Results: The 'intrinsic' brainstem tumors were classified into three types: Expanding, diffuse infiltrative and pure ventral varieties. Only patients with expanding variety of brainstem gliomas were subjected to surgery, mean age 19.2 years (range 4-55 years) and male to female ration mean: 3:2). The tumor location included pons (n=19), midbrain (n=13) and medulla (n=8). Surgical approaches included midline suboccipital (n=28), retromastoid (n=7), subtemporal (n=3) and supracerebellar-infratentorial (n=2). Thirty-two cases with 'diffuse infiltrative' and 'pure ventral' variety were given radiotherapy only. Histology pathology revealed pilocytic variety (n=10), Grade II (n=17) and Grade III (n=13). There was one death in the surgical series (due to aspiration). Complications included meningitis (n=2), wound infection (n=1), chest infection (n=5) and transient mutism (n=1). Follow-up ranged from 3-68 months. Overall, 36 improved /remained same and three worsened in their clinical status at the time of discharge. Conclusion: The surgical management of intrinsic brainstem tumors presents a surgical challenge; radical excision yielded a good outcome in the majority of cases. The authors propose a classification system for 'intrinsic' brainstem tumors for defining surgical strategy. [ABSTRACT FROM AUTHOR]

Background: In upper abdominal malignancies (UAM), due to the presence of multiple inhomogeneous tissues, a wedge-based conformal treatment planning results in high-dose regions inside the target volume. Aim: This study was designed to explore the feasibility of using a field-in-field (FIF) technique in different UAM and its efficacy in reducing the high-dose regions. Materials and Methods: Twelve patients of UAM (which included malignancies of the gastroesophageal junction, stomach, gall bladder, and pancreas) were selected for this study. Computed tomography (CT) scans were performed and three-dimensional conformal wedge plans were generated for all the cases. The same plan was copied with the wedges removed and a FIF plan was generated. The two plans were compared for mean, maximum, and median doses; dose received by 2% (D2) and 98% (D98) of the target volume; volume receiving >107% (V > 107%) and <95% (V < 95%) of the prescribed dose; conformality index (CI); and total monitor units. The doses to critical structures such as liver, kidneys, and spinal cord were also compared. Statistical Analysis: Statistical analysis was performed with SPSS, version 10.0. Results: For all the cases, the FIF technique was better than wedge-based planning in terms of maximum dose, D2, V > 107%, and CI; there was a statistically significant reduction in monitor units. With regard to doses to critical structures, there was marginal dose reduction for the kidneys and spinal cord with FIF as compared to wedge-based planning. Conclusion: The FIF technique can be employed for UAM in place of wedge-based conformal treatment plans. [ABSTRACT FROM AUTHOR]

Aims: Radiotherapy forms an integral part of breast-conserving treatment in early-stage breast cancer. Subcutaneous fibrosis of the treated breast is an important late effect in whole-breast irradiation. The aim of this study was to compare the normal tissue complication probability (NTCP) for radiation-induced fibrosis in treated breast using accelerated partial-breast irradiation (APBI) vs conventional treatment. Materials and Methods: Ten postoperative early-stage breast cancer patients (T1N0M0) were included in this dosimetric analysis. APBI treatment was planned using conformal radiotherapy technique and conventional treatment plans included two tangential portals. All the APBI treatment plans were made with five non-coplanar beams with 6 MV photons. The prescription dose was 38 Gy in 10 fractions for the APBI treatments and 50 Gy in 25 fractions, followed by a boost dose of 16 Gy in 8 fractions, for the conventional treatments. We used Lyman's relative-seriality model and the breast fibrosis NTCP model fitting parameters for the study. Results: The equivalent uniform dose (EUD) was 30.09 Gy and 50.79 Gy in APBI and conventional treatment, respectively. The mean NTCP values for ipsilateral breast fibrosis in APBI and conventional treatment were 0.51 and 25.66%, respectively. Using the paired t-test, a statistically significant difference was seen in the breast fibrosis NTCP values for APBI vs conventional treatment (P<0.001). Conclusions: APBI reduces the ipsilateral breast fibrosis compared to conventional whole-breast treatment in early-stage breast cancer. [ABSTRACT FROM AUTHOR]

Background and Aims: Radiation induced wet desquamation of skin in carcinoma breast patients is a painful condition. In this study topical beclomethasone dipropionate spray was used as prophylaxis with the purpose of reducing risk of the wet desquamation of skin in irradiated field.Materials and Methods: Sixty patients of carcinoma breast were planned for postoperative loco regional radiotherapy (50 Gy in 25 fraction over five weeks) were prospectively randomized into two groups (1) steroid group-patients were advised to use beclomethasone dipropionate spray in irradiated axilla from day one of radiotherapy, (2) control group-patients were not allowed to use any topical agent in irradiated area. Radiation induced skin reaction was noted in terms of erythema, dry desquamation and wet desquamation weekly till end of prescribed 50 Gy dose of the radiation therapy.Statistical Method: Chi-square test was used to see the statistical significance of the difference in wet desquamation between two arms of the study. Chi-square value and P-value was calculated for the difference of wet desquamation in two study arms.Result: In steroid group 4/30 (13.33%) patients developed wet desquamation of the axillary skin at the end of the radiotherapy. For the control group, this figure was 11/30 (36.66%). The difference in wet desquamation of the axillary skin in the two groups was statistically significant (P-value = 0.0369).Conclusion: Topical steroid (beclomethasone dipropionate spray) for skin during radiotherapy significantly reduces the risk of wet desquamation of the skin. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the integral dose to carotid vessels in extended field intensity modulated radiotherapy (IMRT) (including the lower neck nodes in IMRT field) and split field IMRT (using separate single anterior field to treat lower neck nodes) in cancer nasopharynx. Materials and Methods: Dosimetric data from 10 patients of carcinoma nasopharynx, undergoing IMRT, were evaluated in this prospective study. The carotid vessels were contoured from sternoclavicular joints upto the base of skull. IMRT plans were generated for all patients with extended field and split field IMRT techniques using nine coplanar beams with 6 MV photons. A dose of 70 Gy to planning target volume (PTV)70Gy, 59.4 Gy to PTV59.4Gy and 54 Gy to PTV54Gy was delivered in 33 fractions. The dose constraints were similar for both the techniques. The integral dose to the carotid arteries was calculated as the mean dose times the volume (mean dose × volume) in units of liter-gray. Results: The mean dose to the carotid vessels in the extended field IMRT was 63.88 ± 0.97 Gy (mean dose ± SD) and it was 64.43 ± 0.73 Gy for the split field technique. The integral dose in the extended field versus split field technique was 0.29 ± 0.0207 and 0.32 ± 0.0213 liter-gray, respectively. The difference was statistically significant (P < 0.013). Conclusions: Extended field IMRT delivers a slightly lower integral dose to carotid arteries in treatment of cancer nasopharynx while maintaining good dose homogeneity to the PTV54Gy and can be preferred over split field radiotherapy. [ABSTRACT FROM AUTHOR]

Purpose: Field matching poses challenges in craniospinal irradiation (CSI) as it leads either to underdosage or overdosage in the junctional area. A simple technique for CSI in pediatric patients is proposed. Materials and Methods: Computed tomography scans were performed in the prone position. Two lateral cranial fields and a direct posterior spinal field were planned with a common central axis. Half-beam-blocked cranial fields with zero collimator rotation were used for treating the cranium. A half-beam-blocked field defined with jaws was used to treat the spinal column at an extended sourceto-surface distance. Before treating the patient, matching of the cranial and spinal field junction along the central axis was verified with an extended dose range film. Results and Conclusion: The technique described is simple and easy to implement and can be applied to pediatric patients undergoing CSI. This method has the potential to reduce daily setup time and setup errors. This technique is ideally suitable for patients with spinal fields less than 30 cm. [ABSTRACT FROM AUTHOR]

Sarcomatoid carcinomas are rare tumors. These tumors have been reported at other sites, but head and neck origin is extremely uncommon. We report here a rare case of sarcomatoid carcinoma involving the maxilla. Only four such cases with maxillary origin have been discussed in English literature earlier. As compared to squamous cell carcinoma of maxilla, this variant is associated with poor prognosis and advanced disease at presentation, as was also seen in our case. There are no standard recommendations for management owing to the rarity of this histology. Surgery and radiotherapy form the mainstays of treatment. Exploration of the role of chemotherapy and novel targeted therapy agents is warranted in order to improve treatment results. [ABSTRACT FROM AUTHOR]

Purpose: This study was mainly framed to study the difference in tumor volumes as seen on computed tomography (CT) and magnetic resonance (MR) and their significance in planning.Materials and Methods: Twenty-five patients with brain tumor of different diagnoses who underwent stereotactic radiotherapy were included in this study. CT and MR imaging was done for all the patients with 2.5 mm slice thickness. The CT tumor volume and MR tumor volume were measured and compared with each other. The center of mass (CM) of the tumor volume delineated on CT and MR were computed and the shift between the two CMs was determined.Results: The mean and median volume of the tumor as measured from MR scans was 19.67 cc +/- 13.73 and 16.13 cc (range: 3.25 cc-50.37 cc). Similarly, the mean and median volume of the tumor as measured from CT scans was 15.05 cc +/- 10.13 and 11.63 cc (range: 3.0 cc-36.25 cc) respectively. The mean and median CM shift between CT and MR was 5.47 mm and 5.21 mm respectively.Conclusion: The study demonstrates that MR is an indispensable imaging modality in radiotherapy for planning brain tumors. [ABSTRACT FROM AUTHOR]

Sweat gland carcinoma is a rare skin tumor. The tumor has propensity to spread to lymph nodes and distant metastases has been reported. Their exact incidence in the Indian setting is not known. Aspects related to treatment are also not clearly defined. Though surgery forms the initial treatment approach, adjuvant treatment has not been properly explored. We report here a case of sweat gland carcinoma with bilateral lung metastases. [ABSTRACT FROM AUTHOR]