Carotid sparing hypofractionated tomotherapy in early glottic cancers: Refining image guided IMRT to improve morbidity

Objective: Carotid artery damage has been reported secondary to radiotherapy. We report the feasibility of implementing hypofractionated laryngeal irradiation using carotid sparing tomotherapy (HT) and analyze the image guidance (IG) policy. Materials and Methods: Five patients with early glottic cancer (EGC) had radiotherapy using 3D conformal technique (conf) while repeat treatment plans were produced with helical tomotherapy using carotid sparing techniques (cstomo). Inverse and forward planned dose volume histograms were analyzed. Three hundred and sixty four daily images of 14 patients having daily Megavoltage head and neck CT imaging prior to irradiation were analyzed to assess errors. Results: There was no significant difference in the maximum and mean dose to the PTV (P = 0.058, 0.66). The left / right carotid median doses were significantly less in the cstomo plans as compared to conf plans (P = 0.0001/ 0.026). Cstomo plans had significantly better PTV Conformity Index (CI) (P = 0.0006) with comparable Homogeneity Index. A CTV-PTV margin of 5.3, 4, 5.3 cm in the 3 axes were calculated using Van Herks formula. After average shifts from imaging for first 5 fractions (AS5) were applied to remaining fractions, the residual shifts in the calculated CTV-PTV margins reduced to 2.9, and 2.1 in the X, Y axes respectively allowing further adaptation of PTV margin from fraction 6. Conclusions: Carotid sparing was possible using cstomo plans with significantly better conformity. Applying AS5 could enable us to reduce the PTV (3 mm) margin in X, Y axes for the remaining 15 fractions

Dose escalation in image-guided, intensity-modulated radiotherapy of carcinoma prostate: Initial experience in India

Background : Increasing incidence and significant stage migration from distant metastases to a localized disease, due to screening application of PSA, is taking place in carcinoma prostate. Also, role of radiotherapy is increasing in carcinoma prostate due to rapid strides in technology. Aim: The present retrospective study, evaluates escalating the dose in the treatment of localized carcinoma prostate using integration of multiple advanced techniques. Settings and Design: The settings designed are: a) use of gold seed internal fiducial markers: b) clinical application of emerging Megavoltage Cone Beam Computed Tomography (MVCBCT) technology for Image Guided Radiotherapy (IGRT); c) Intensity Modulated Radiotherapy (IMRT); d) adopting biochemical method for follow-up. Methods and Material: Twelve consecutive, biopsy proven localized cancer of prostate patients, treated with dose escalation IMRT& IGRT protocol between August 2006 and January 2008, were analyzed. Gold seed markers in prostate were used for daily localization with MVCBCT or Electronic Portal Imaging (EPI). All patients underwent clinical and biochemical follow-up. Statistical Analysis& Results : Planned dose of 7740 cGy was delivered in 10 out of 12 patients (83%). While one patient had migration of maximum of 3 mm, two others had 1 mm migration of one seed during course of treatment. One patient (8%) developed Grade II proctitis at 12th month. During the mean follow-up duration of 12.2 months, 92% (11/12) had biochemical control within 3 months of treatment. Conclusions: IGRT technique using MVCBCT for implanted fiducial gold seed localization was feasible for IMRT dose escalation in carcinoma prostate with excellent results

Dose escalation in image-guided, intensity-modulated radiotherapy of carcinoma prostate: Initial experience in India

Background : Increasing incidence and significant stage migration from distant metastases to a localized disease, due to screening application of PSA, is taking place in carcinoma prostate. Also, role of radiotherapy is increasing in carcinoma prostate due to rapid strides in technology. Aim: The present retrospective study, evaluates escalating the dose in the treatment of localized carcinoma prostate using integration of multiple advanced techniques. Settings and Design: The settings designed are: a) use of gold seed internal fiducial markers: b) clinical application of emerging Megavoltage Cone Beam Computed Tomography (MVCBCT) technology for Image Guided Radiotherapy (IGRT); c) Intensity Modulated Radiotherapy (IMRT); d) adopting biochemical method for follow-up. Methods and Material: Twelve consecutive, biopsy proven localized cancer of prostate patients, treated with dose escalation IMRT& IGRT protocol between August 2006 and January 2008, were analyzed. Gold seed markers in prostate were used for daily localization with MVCBCT or Electronic Portal Imaging (EPI). All patients underwent clinical and biochemical follow-up. Statistical Analysis& Results : Planned dose of 7740 cGy was delivered in 10 out of 12 patients (83%). While one patient had migration of maximum of 3 mm, two others had 1 mm migration of one seed during course of treatment. One patient (8%) developed Grade II proctitis at 12th month. During the mean follow-up duration of 12.2 months, 92% (11/12) had biochemical control within 3 months of treatment. Conclusions: IGRT technique using MVCBCT for implanted fiducial gold seed localization was feasible for IMRT dose escalation in carcinoma prostate with excellent results

Phenotypic similarities within the morphologic spectrum of DICER1-associated sarcomas and pleuropulmonary blastoma: Histopathologic features guide diagnosis in the LMIC setting.

Extrapulmonary DICER1-associated sarcomas (DS) can harbor morphological features overlapping with pleuropulmonary blastoma. We report 3 children with intracranial and genital tract sarcomas, suspected to have DS based on a heterogeneous yet defining combination of spindle-cell sarcomatous and blastemal morphology, with rhabdomyomatous differentiation. Foci of immature cartilage at diagnosis (n=2/3) and increased neuroepithelial differentiation at recurrence (n=1) were noted. Morphological suspicion prompted somatic testing at reference centers, confirming likely biallelic, loss-of-function and ‘hotspot’ missense DICER1 variants in all 3 tumors. This can serve as a model for this diagnosis in resource-limited settings and has implications for germline testing, surveillance, and tumor management