Total ablative stereotactic body radiotherapy to primary and oligometastatic renal cell carcinoma in medically inoperable cases: An institutional analysis.

Introduction: Stereotactic body radiotherapy (SBRT) has been found to be an effective and safe modality with excellent oncological outcome in medically inoperable primary renal cell carcinoma (RCC) and oligometastases. There is scarcity of data on the synchronous delivery of SBRT to primary and oligometastatic RCC in patients unfit for nephrectomy. Here, we report the findings of a retrospective study of prospectively collected data on "total ablative SBRT." Methods: Oligometastatic RCC patients with intact primary tumors were enrolled between May 2021 and June 2022. SBRT was synchronously delivered to the primary tumor and metastases. Demographics, treatment, oncologic outcomes, and toxicity were assessed. Kaplan-Meier estimates were generated for oncologic outcomes. The primary endpoint of this study was feasibility and tolerability. Results: Eleven patients were enrolled between May 2021 and June 2022. One patient died at 2 months after SBRT due to viral pneumonitis (possibly COVID pneumonia). Nine patients (82%) had metastatic disease, while 2 (18%) were stage II. The average maximal diameter of primary was 68.7 mm (range, 23-128 mm). The SBRT doses for primary and metastasis ranged from 40 to 55 Gray (Gy) in 5 to 7 fractions and 22 to 40Gy in 2 to 5 fractions, respectively. The median follow-up period was 10.5 months (Range: 4-15 months). Response assessment was available for ten patients. Local control, marginal control, regional control and initial oligometastatic control (OMC) rates were 100%. OMC declined to 87.5% as one patient had recurrence in irradiated subcarinal lymphnode at 7 months. The metastatic control rate was 80% and loco-regional progression-free survival was 8 months (range, 4-15 months). Toxicities were minimal and manageable. At the last follow-up, 7 of 11 patients were alive with an overall survival of 63.5%. Six patients received systemic therapy after SBRT. Conclusions: Synchronous delivery of SBRT to primary and oligometastatic sites in patients unfit for nephrectomy was feasible and tolerable with good locoregional control. The total ablative SBRT strategy needs to be explored in similar cohorts.

Diagrammatic Approach to Delineate Phrenic Nerve in Central Lung Tumors.

Incremental use of high-dose radiation therapy (RT) with SABR in thoracic tumors has led to identification of many unusual toxicities (chest wall pain, rib fractures, vascular perforation, brachial plexopathy) and consequently additional organs at risk (OARs; chest wall, ribs, bronchial wall, carotid artery, brachial plexus). Phrenic nerve is another structure that may be affected at any point during its long course from origin until end, although symptomatic toxicities have been reported rarely in the setting of reirradiation, large-volume irradiation such as mantle field, or SABR. We undertook a prospective study to describe the delineation of phrenic nerve course on RT planning computed tomography scan as an OAR. An anonymized RT planning computed tomography scan of neck and thorax (1.5-mm slice thickness, intravenous contrast) was used for the study. Radiology textbooks and publications were reviewed, and the course was delineated with the help of 2 radiologists and 6 radiation oncologists well versed with thoracic radiologic anatomy. A step-by-step description in the form of a pictorial essay is given. The adjacent structures including cervical vertebrae, cervical and mediastinal vessels, lungs, heart, and so on were identified, and the course of phrenic nerve on either side is described in relation to these structures. Delineation of the phrenic nerve as an OAR is challenging but feasible. We recommend routine delineation of the phrenic nerve as an OAR during thoracic RT. Although specific dose constraints are not known yet, unnecessary dose to the same during RT planning should be minimized.

Current status and future readiness of Indian radiation oncologists to embrace prostate high-dose-rate brachytherapy: An Indian Brachytherapy Society survey.

Purpose: This survey aimed to understand the practice pattern and attitude of Indian doctors towards prostate brachytherapy. Material and methods: A 21-point questionnaire was designed in Google form and sent to radiation oncologists practicing in India, using texts, mails, and social media. Responses were collated, and descriptive statistical analysis was performed. Results: A total of 212 radiation oncologists from 136 centers responded to the survey questionnaire, with majority (66%) being post-specialty training > 6 years. We found that about 44.3% (n = 94) of respondents do not practice interstitial brachytherapy for any site, and majority (83.3%, n = 175) do not practice high-dose-rate (HDR) prostate brachytherapy. Only 2.8% (n = 6) of doctors preferred boost by brachytherapy compared with 38.1% (n = 80) of respondents, who favored stereotactic body radiation therapy (SBRT) boost. When asked about the indication of HDR prostate brachytherapy in Indian setting, 32.5% (n = 67) of respondents favored monotherapy, 46.1% (n = 95) of oncologists thought boost as a good indication, and 21.4% (n = 44) preferred re-irradiation/salvage setting. The most cited reason for prostate brachytherapy not being popularly practiced in India was lack of training (84.8%, n = 179). It was also noted that out of 80 respondents who practiced SBRT for prostate boost, 37 would prefer HDR brachytherapy boost if given adequate training and facilities. Conclusions: The present survey provided insight on practice of prostate brachytherapy in India. It is evident that majority of radiation oncologists do not practice HDR prostate brachytherapy due to lack of training and infrastructure. Indian physicians are willing to learn and start prostate brachytherapy procedures if dedicated training and workshops are organized.

Nidus delineation and dosimetric comparison in arteriovenous malformation in stereotactic radiosurgery by using MRI and 3DCT angiography.

Purpose/Objectives: Accurate delineation of target is key to any successful radiosurgery. C-arm Dyna CT/ 3DCT angiography (3DCTA) has the potential of improving the accuracy of nidus delineation in intracranial arteriovenous malformations (AVM) due to high temporo-spatial resolution of vessel architecture. Here, we present a comparison of nidus delineation and dosimetric parameters between digital 3DCTA and MRI. Materials/Methods: Ten consecutive patients treated for intracranial AVMs were included in this study. All patients underwent MRI/MRA, and 3DCTA and all images were co-registered. AVM were delineated using 3DCTA (GTV3DCTA) and contrast enhanced MRI/MRA (GTVMRI). Hausdorff distance (HD) matrices and dice similarity coefficient (DSC) matrices were analysed. Stereotactic radiosurgery plans were developed for both the volumes for all patients and statistical analysis were performed with T-test. Results: Mean volumes of GTV3DCTA and GTVMRI were 1.771 cc (SD 1.794cc, range 0.124-4.191cc) and 2.183cc (SD 2.16cc, range 0.221-6.133cc), respectively. Significant deviation (p=0.018) was found when taking GTVMRI as a primary and comparing it to GTV3DCTA (MD=0.723cc±0.816cc). Similar result was observed with GTV3DCTA as primary and GTVMRI as secondary (MD=0.188cc, SD=0.193cc, p=0.024). Maximum HD was in the range of 1.71 to 7.44mm (mean=4.27mm, SD=1.56). For GTV3DCTA based plans, significant deviation was found between GTVMRI and GTV3DCTA in dose coverage and the mean difference was 22.17% (SD 16.73). In GTVMRI based plans, the mean CIRTOG deteriorated from 1.33 to 2.18 for GTVMRI and GTV3DCTA, respectively. Significant deviation was found in CIRTOG (0.005) and mean deviation was 0.86(SD=0.72) when comparing GTVMRI and GTV3DCTA. Highly significant (p=0.002) deviation was found in CIPaddick between GTVMRI and GTV3DCTA for GTVMRI based plans with mean difference of 0.26(SD=0.4, for GTVMRI=0.3, GTV3DCTA=0.46). Conclusion: Nidus volume was significantly altered with the use of 3DCTA compared to that of MRA/MRI images. Multimodality imaging is crucial for accurate target delineation, and successful radiosurgical obliteration of nidus.

Commissioning and Dosimetric Results of an Indigenously Developed Intra-Vaginal Template for Interstitial Plus Intracavitary High dose Rate Image-Guided Brachytherapy of Advanced Cervix Cancer.

Aim: The goal of this study is to discuss the commissioning and dosimetric parameters achieved during the clinical implementation of an indigenously developed intracavitary (IC) plus interstitial (IS) template for high dose rate (HDR) image-guided brachytherapy (IGBT) in cancer (Ca) cervix. We want to discuss our achieved values of cumulative equi-effective doses (EQD2) for high-risk clinical target volume (HRCTV) and organ at risk (OAR) and compare it with available published results. Materials and Methods: Medanta anterior oblique/lateral oblique template has a total of 19 needles including the central tandem. For commissioning the template with needles, the indigenously made acrylic phantom was used. Oblique and straight needles were placed inside the acrylic phantom and a computed tomography (CT) scan was performed. Sixteen patients were treated in HDR IGBT using this template after external-beam radiotherapy. The IGBT plans were evaluated based on EQD2 of target coverage i.e., dose received by 98% (D98%_HRCTV), 90% (D90%_HRCTV), and 50% (D50%_HRCTV) volume of HRCTV, and dose received by 2 cc (D2cc) and 0.1 cc (D0.1cc) of OAR using linear quadratic (LQ) radiobiological model. Results: The autoradiographic in radiochromic film shows that the distance between the needle tip and the middle of the source position is 6 mm. The mean D98%_HRCTV and D90%_HRCTV was 76.8 Gy (range: 70-87.7 Gy, P < 0.01) and 84.49 Gy (range: 76.6-96.7 Gy, P < 0.01), respectively. Mean EQD2 of D2cc of the bladder, rectum, and sigmoid was 85.6 Gy (range: 77.5-99.6 Gy, P < 0.03), 74.3 Gy (range: 70.9-76.7 Gy, P < 0.05), and 58.3 Gy (range: 50.6-67.9 Gy, P = 0.01), respectively. The mean total reference air kerma at a 1 m distance is 0.489cGy (range: 0.391-0.681cGy). Conclusions: The indigenously developed template could attain satisfactory standards in terms of set parameters for commissioning and acceptable dose volume relations in our clinical use for treating the advanced Ca cervix patients who need IC + IS type of HDR IGBT. The comparative analysis with contemporary applicators was acceptable.

CyberKnife Stereotactic Ablative Radiotherapy for Recurrent or Oligometastatic Gynecological Cancers.

Purpose Use of stereotactic ablative radiotherapy (SABR) in the treatment of recurrent or metastatic lesions from a primary gynecologic cancer is a relatively new concept. The present study aims to assess the safety, efficacy, and possible toxicity profile of CyberKnife SABR, recurrent or metastatic disease. Materials/Methods CyberKnife VSI-based SABR was offered to 20 oligometastatic/recurrent gynecological cancer patients between 2013 and 2019. Patient, tumor, and treatment characteristics including radiotherapy details, clinical outcome in terms of local control rates, and toxicities are reported in this study. Results Twenty-five recurrent or oligometastatic lesions for 20 primary gynecologic cancer patients including cervical ( n = 8), ovarian ( n = 6), endometrial ( n = 5), and vulvar ( n = 1) cancers were analyzed. Of these, 4 (16%) were intracranial lesions and remaining 21 (84%) were extracranial, consisting of 14 (67%) extrapelvic and 7 (33%) pelvic lesions. The median SABR dose delivered was 60 Gy biologically effective dose (range 42-133 Gy) in an average of four fractions (range 1-6). The mean follow-up was 18 (range 2-70) months. Local tumor control was achieved in 82% of patients. There was no grade ≥ 3 toxicity recorded. Conclusion Our study results suggest that CyberKnife SABR is an effective treatment modality with no major morbidity in patients with recurrent or oligometastatic gynecological cancers.

Dosimetric Comparison of Robotic and Linear Accelerator Multi-Leaf Collimator-Based Stereotactic Radiosurgery for Arteriovenous Malformation.

PURPOSE: To investigate the dosimetric comparison of different collimators which are used in robotic radiosurgery (cyberknife-CK) and linear accelerator (LINAC) for stereotactic radiosurgery (SRS) in arteriovenous malformation (AVM). MATERIALS AND METHODS: Twenty-five AVM patients were planned in CK using FIXED cone, IRIS collimator, and multi-leaf collimator (MLC) based in LINAC. Dosimetric comparison was performed using Paddick conformity index (CIPaddick) and International Commission on Radiation Units and measurements (ICRU) homogeneity index (HIICRU), gradient score (GS), normal brain dose received by 10cc (D10cc) and critical structure (brain stem, optic chiasma, optic nerves) doses. Paired sample t-test was used for statistical analysis. RESULTS: Mean treatment volume was 3.16cc (standard deviation ± 4.91cc). No significant deviation (P =0.45, 0.237 for FIXED vs. IRIS and FIXED vs. MLC, respectively) was found in target coverage. For CIPaddick, the mean difference (MD) between FIXED- and MLC-based plans was 0.16(P = 0.001); For HIICRU, difference between FIXED and IRIS was insignificant (0.5, P = 0.823); but, when FIXED versus MLC, the deviation was 7.99% (P = 0.002). In FIXED- and MLC-based plans, significant difference was found in GS70 and GS40 (P < 0.041 and 0.005, respectively). MD between FIXED- and MLC-based plans for normal brain for 5Gy, 10Gy, 12Gy, and 20Gy were 36.08cc (P = 0.009), 7.12cc (P = 0.000), 5.84cc (P = 0.000) and 1.56cc (P = 0.000), respectively. AVM volume <0.7cc should be treated with CK FIXED and >0.7cc were treated by using FIXED or IRIS collimators. AVM volume > 1.4cc can be treated by either LINAC MLC-based SRS or CK. CONCLUSION: Our study shows CK collimator (IRIS and FIXED) could be able to treat brain AVMs in any size. Linac MLC-based SRS has some limitations in terms of conformity and low-dose spillage, and advantages like reduced treatment time and MU.

Artificial intelligence in brachytherapy: a summary of recent developments.

Artificial intelligence (AI) applications, in the form of machine learning and deep learning, are being incorporated into practice in various aspects of medicine, including radiation oncology. Ample evidence from recent publications explores its utility and future use in external beam radiotherapy. However, the discussion on its role in brachytherapy is sparse. This article summarizes available current literature and discusses potential uses of AI in brachytherapy, including future directions. AI has been applied for brachytherapy procedures during almost all steps, starting from decision-making till treatment completion. AI use has led to improvement in efficiency and accuracy by reducing the human errors and saving time in certain aspects. Apart from direct use in brachytherapy, AI also contributes to contemporary advancements in radiology and associated sciences that can affect brachytherapy decisions and treatment. There is a renewal of interest in brachytherapy as a technique in recent years, contributed largely by the understanding that contemporary advances such as intensity modulated radiotherapy and stereotactic external beam radiotherapy cannot match the geometric gains and conformality of brachytherapy, and the integrated efforts of international brachytherapy societies to promote brachytherapy training and awareness. Use of AI technologies may consolidate it further by reducing human effort and time. Prospective validation over larger studies and incorporation of AI technologies for a larger patient population would help improve the efficiency and acceptance of brachytherapy. The enthusiasm favoring AI needs to be balanced against the short duration and quantum of experience with AI in limited patient subsets, need for constant learning and re-learning to train the AI algorithms, and the inevitability of humans having to take responsibility for the correctness and safety of treatments.

Use of ultrasound in image-guided high-dose-rate brachytherapy: enumerations and arguments.

Inherently, brachytherapy is the most conformal radiotherapeutic technique. As an aid to brachytherapy, ultrasonography (USG) serves as a portable, inexpensive, and simple to use method allowing for accurate, reproducible, and adaptive treatments. Some newer brachytherapy planning systems have incorporated USG as the sole imaging modality. Ultrasonography has been successfully used to place applicator and dose planning for prostate, cervix, and anal canal cancers. It can guide placement of brachytherapy catheters for all other sites like breast, skin, and head and neck cancers. Traditional USG has a few limitations, but recent advances such as 3-dimensional (3D) USG and contrast USG have enhanced its potential as a dependable guide in high-dose-rate image-guided brachytherapy (HDR-IGBT). The authors in this review have attempted to enumerate various aspects of USG in brachytherapy, highlighting its use across various sites.

Quantification of coronary artery motion and internal risk volume from ECG gated radiotherapy planning scans.

BACKGROUND: Radiotherapy for carcinoma of breast and thoracic structures involves inadvertent radiation to heart and coronary arteries (CA). Coronary artery stenosis in high radiation dose segments has been documented. Cardiac and respiratory motion induced displacement of CA and internal risk volume (IRV) margin remains inadequately quantified. MATERIAL AND METHODS: Twenty cases of carcinoma breast, lung and lung metastasis were enrolled in this study. ECG gated intravenous contrast enhanced computed tomography (CECT) scans were performed in inspiratory breath hold (IBH) and expiratory breath hold (EBH). The images were segregated into inspiratory systole (IS), inspiratory diastole (ID), expiratory systole (ES) and expiratory diastole (ED) sets. Left anterior descending (LAD), limited segment of LAD close to chest wall (short LAD), right coronary artery (RCA), Left circumflex artery (LCX) and left ventricle (LV) were delineated in all four sets. Mean displacements in systole versus diastole and inspiration versus expiration were calculated in three co-ordinates [anterio-posterior (Z), left-right (X) and cranio-caudal (Y)]. RESULTS: Mean of displacement (mm) between systole and diastole (IS versus ID; and ES versus ED) in X, Y, Z co-ordinates were: LAD 3.0(±1.6), 2.8(±1.5), 3.6(±2.0); Short-LAD 3.0(±1.1), 0.8(±0.4), 2.4(±0.6); LV 2.4(±1.6), 1.7(±1), 5.0(±1.5); LCX 4.9(±1.6), 2.9(±1.3), 5.1(±1.9); RCA 6.6(±2.2), 3.6(±2.1), 5.9(±2.2). Mean displacement between inspiration and expiration (IS versus ES; and ID versus ED) in X, Y, Z axes were: LAD 3.3(±1.5), 8.0(±3.4), 3.8(±1.8); Short-LAD 2.7(±1), 12.2(±4.4), 3.3(±1.5); LV 2.9(±1.4), 9.8(±3.3), 4.7(±1.9); LCX 2.9(±.8), 9.7(±3.2), 6.2(±2.5); RCA 2.6(±1.3), 7.6(±2.5), 3.8(±1.7). CONCLUSION: Radial (RM), cranio-caudal margin (CC) of 7mm, 4mm in breath-hold radiotherapy whereas RM, CC of 7mm, 13mm respectively in free breath radiotherapy will cover the range of motions of CA, LV and can be recommended as IRV for these structures.

Chemoradiation in elderly patients with head and neck cancers: a single institution experience.

AIMS: To evaluate the efficacy and toxicity of concurrent chemoradiation in patients with head and neck cancers aged 65 and older. MATERIALS AND METHODS: Thirty-two elderly patients were treated with radical chemoradiation. Twenty-six (81.3%) out of thirty-two patients had stage III-IV disease. Twenty-nine (90.6%) patients received concurrent weekly cisplatin or carboplatin, 3 (9.4%) patients received concurrent cetuximab or nimotuzumab. Total dose of radiotherapy ranged from 66Gy to 70Gy. RESULTS: Twenty-nine patients (90.6%) completed at least 5cycles of concurrent chemotherapy. Twenty-four (77.6%) patients achieved complete response. Fourteen (45.2%) patients experienced grade 3 mucositis. None of our patients developed grade 3 or above hematological toxicity. Loco-regional control and overall survival at 2year were 71.6% and 88.9%, respectively. CONCLUSIONS: Chemoradiation in elderly patients with high precision radiotherapy is a feasible option.

Dosimetric comparison between Volumetric Modulated Arc Therapy (VMAT) vs Intensity Modulated Radiation Therapy (IMRT) for radiotherapy of mid esophageal carcinoma.

AIMS: Dosimetric comparison of VMAT with IMRT in middle third esophageal cancer for planning target volume (PTV) and organs at risk (OAR). MATERIALS AND METHODS: Ten patients in various stages from I‒III were inducted in the neo-adjuvant chemoradiation protocol for this study. The prescribed dose was 4500 cGy in 25 fractions. Both VMAT and IMRT plan were generated in all cases and Dose Volume Histogram (DVH) comparative analysis was performed for PTV and OAR. Paired t-test was used for statistical analysis. RESULTS: The PTV Dmean and D95 in IMRT and VMAT plan were 4566.6±50.6 cGy vs 4462.8±81.8 cGy (P=0.1) and 4379.8±50.6 cGy Vs 4424.3±109.8 cGy (P=0.1), respectively. The CI and HI for PTV in IMRT vs VMAT plans were 0.96±0.02 vs 0.97±0.01 (P=0.4) and 10.58±3.07 vs 9.45±2.42 (P=0.2), respectively. Lung doses for VMAT vs IMRT were 4.19 vs 2.59% (P=0.03) for V35-7.63 vs 4.76% (P=0.01) for V30-13.6 vs 9.98% (P=0.01) for V25-24.77 vs 18.57% (P=0.04) for V20-46.5 vs 34.73% (P=0.002) for V15. The Mean Lung Dose (MLD) was reduced by VMAT technique compared to IMRT; 1524.6±308.37 cGy and 1353±186.32 cGy (P=0.012). There was no change in Dmax to spinal cord in both the techniques. There was a dose reduction by VMAT compared to IMRT to the heart but it was statistically insignificant; V35-6.75% vs 5.55% (P=0.223); V30-12.3% vs 10.91% (P=0.352); V25-21.81% vs 20.16% (P=0.459); V20-38.11% vs 32.88% (P=0.070); V15-61.05% vs 54.2% (P=0.10). CONCLUSION: VMAT can be a better option in treating mid esophageal carcinoma as compared to IMRT. The VMAT plans resulted in equivalent or superior dose distribution with a reduction in the dose to lung and heart.

Incidental radiation to axilla in early breast cancer treated with intensity modulated tangents and comparison with conventional and 3D conformal tangents.

PURPOSE: To analyze incidental radiation doses to minimally dissected axilla with Intensity modulated radiotherapy (IMRT), 3D conformal radiotherapy (3DCRT) and standard tangents (ST). METHODS & MATERIALS: We prospectively evaluated incidental radiation to axilla in fifty cases of early breast cancer treated with breast conservation surgery with sentinel node biopsy alone followed by whole breast irradiation with IMRT. Three plans were devised for each CT dataset, comprising ST, 3DCRT and IMRT tangents. Doses to axillary nodal levels I, II and III were evaluated for mean dose, V95, V90, V80 and V50. Comparisons were made using ANOVA. RESULTS: The mean doses delivered to axilla by the three techniques (IMRT, 3DCRT, ST) were: 78% (range 67-90, SD ± 5.2%), 80% (63-95, ±7.5%) and 87% (73-98, ±4.8%) for level I (IMRT vs ST; p = 0.037); 70% (46-89, ±12.4%), 72% (34-93, ±15.5%) and 65% (29-87, ±11.8%) for level II; and 51% (28-76, ±11.1%), 53% (19-86, ±13.7%) and 41% (6-72, ±10.6%) for level III, respectively. V90 values (volume receiving 90% of dose) for the three techniques were 49% (43-53, ±2.7%), 57% (51-65, ±3.1%) and 73% (65-80, ±3.4%) for level I (IMRT vs. ST; p = 0.029); 35% (26-42, ±4.7%), 41% (33-50, ±4.2%) and 25% (17-36, ±4.5%) for level II (IMRT vs ST; p = 0.068); and 15% (9-22, ±3.4%), 16% (10-24, ±3.7%) and 8 (5-12, ±3.1%) for level III (IMRT vs ST; p = 0.039), respectively. CONCLUSION: Axillary levels I and II (lower axilla) receive substantial amount of incidental radiation doses with all the three techniques; however, conformal techniques (IMRT, 3DCRT) deliver significantly lesser incidental radiation to lower axilla than ST technique.

Malignant obstructive jaundice - brachytherapy as a tool for palliation.

PURPOSE: Malignant obstructive jaundice (MOJ) is relieved by stenting via endoscopic retrograde cholangiopancreatography (ERCP) or percutaneous transhepatic cholangiography and biliary drainage (PTCD). Stent occlusion rates of 30-45% have been reported in literature due to tumor ingrowth or overgrowth. We prospectively evaluated the feasibility and the role of intraluminal brachytherapy (ILBT) in preventing stent blockage in patients with MOJ after PTCD and stenting. MATERIAL AND METHODS: Twelve patients with MOJ who underwent PTCD followed by self expanding metallic stent (SEMS) placement were prospectively enrolled in this study. Written informed consent was obtained. Intraluminal brachytherapy was done once patient was stable and serum bilirubin was less than 2 mg% or 50% of baseline value. On the day of ILBT, 6 French brachytherapy catheters were placed across malignant stricture under fluoroscopic guidance with placement of the tip 1 cm distal to stricture. A dose of 10 to 14 Gy was delivered at 1 cm from central axis of the source. Suitable patients also received external beam radiotherapy (EBRT) with weekly concurrent chemotherapy. RESULTS: All patients tolerated the procedure well with minimal acute and late toxicities. Duodenal ulceration was observed in 1 patient. At a mean follow up of 10.25 months (5-24 months), stents were patent in 10/12 subjects and stent patency duration of 9.8 months (5-22) was reported. CONCLUSIONS: Intraluminal brachytherapy post PTCD is feasible and effective in preventing stent occlusion with minimal acute and late toxicities.

Frame-based radiosurgery: Is it relevant in the era of IGRT?

PURPOSE: To assess the setup errors and intrafraction motion in patients treated with frame-based and frameless stereotactic radiosurgery (SRS). MATERIALS AND METHODS: Ten patients treated with frame-based and six patients treated with frameless radiosurgery were prospectively enrolled in the study. Leksell frame was used for frame-based and a customized uniframe orfit cast for frameless techniques. Cone beam computed tomography (CBCT) scans were taken immediately before and after each treatment to evaluate the positional accuracy and corrections applied with the use of hexapod couch for both groups. RESULTS: The mean translational shifts with frame-based SRS were 1.00 ± 0.30 mm in the lateral direction (X), 0.20 ± 1.20 mm in craniocaudal direction (Y) and -0.10 ± 0.31 mm in the anteroposterior direction (Z). The rotational shifts for frame-based treatments were as follows: roll 0.32 ± 0.70, pitch 0.44 ± 0.66 and yaw 0.20 ± 0.4. For frameless SRS, translational shifts were -0.40 ± 0.90, 1.10 ± 1.10, and 0.50 ± 1.30 mm in X, Y, and Z directions, respectively, and rotational shifts were -0.11 ± 0.78, 0.20 ± 0.44, and 0.29 ± 0.35 in roll, pitch, and yaw, respectively. Intrafraction shifts with frame-based SRS were: X = 0.60 ± 1.80 mm, Y = 0.20 ± 0.60 mm, and Z = 0.00 ± 0.05 mm; and rotational shifts were: roll 0.01 ± 0.27, pitch 0.06 ± 0.15, and yaw 0.01 ± 0.09. For frameless SRS, these were: X = 0.11 ± 0.20 mm, Y = 0.20 ± 0.40 mm, and Z = 0.20 ± 0.20 mm and rotational shifts were: roll 0.09 ± 0.23, pitch 0.00 ± 0.12, and yaw 0.00 ± 0.09. CONCLUSIONS: In our experience, set up accuracy of frameless SRS is as good as frame-based SRS. With availability of verification methods such as CBCT and hexapod couch, an accurate and precise treatment delivery is feasible with frameless techniques.

Deep vein and artery thrombosis associated with cetuximab-based chemoradiotherapy.

Molecular targeted agents have lower hematological toxicity. However, specific side-effects such as allergic rashes, skin reactions and high cost limit their use. We report a case of 35-year-old male patient with carcinoma of left tonsil treated with concurrent cetuximab and radiotherapy. After four weeks of treatment, the patient developed sudden onset of pain in the left calf region radiating to the left foot. Doppler study of the left lower limb revealed complete thrombosis of superficial femoral, popliteal and proximal tibial arteries and veins and no flow in anterior tibial artery and lower posterior tibial artery. Emergency embolectomy was done. After 48 h of observation, no improvement was noted. A repeat Doppler examination showed similar finding. Ultimately a left lower limb amputation was done. We report simultaneous arterio-venous thrombosis associated with cetuximab-based chemoradiotherapy. Oncologists should be aware of this possible complication to undertake early intervention.

Synchronous malignant vagal paraganglioma with contralateral carotid body paraganglioma treated by radiation therapy.

Paragangliomas are rare tumors and very few cases of malignant vagal paraganglioma with synchronous carotid body paraganglioma have been reported. We report a case of a 20-year old male who presented with slow growing bilateral neck masses of eight years duration. He had symptoms of dysphagia to solids, occasional mouth breathing and hoarseness of voice. Fine needle aspiration cytology (FNAC) performed where he lived showed a sinus histiocytosis and he was administered anti-tubercular treatment for six months without any improvement in his symptoms. His physical examination revealed pulsatile, soft to firm, non-tender swellings over the anterolateral neck confined to the upper-mid jugulo-diagastric region on both sides. Direct laryngoscopy examination revealed a bulge on the posterior pharyngeal wall and another over the right lateral pharyngeal wall. Magnetic resonance imaging (MRI), 99mTc-labeled octreotide scan and angiography diagnosed the swellings as carotid body paraganglioma, stage III on the right side with left-sided vagal malignant paraganglioma. Surgery was ruled out as a high morbidity with additional risk to life was expected due to the highly vascular nature of the tumor. The patient was treated with radiation therapy by image guided radiation to a dose of 5040cGy in 28 fractions. At a follow-up at 16 months, the tumors have regressed bilaterally and the patient can take solids with ease.

Circadian variation in radiation-induced intestinal mucositis in patients with cervical carcinoma.

BACKGROUND: Mucositis, a radiotherapy-associated toxicity, is an important factor determining morbidity and treatment compliance. Gastrointestinal mucositis in patients undergoing radiotherapy may also depend on time of administration of radiation in addition to several other factors. The presence of any correlation between the severity of acute gastrointestinal mucositis in cervical carcinoma patients and the time of irradiation was prospectively evaluated. METHODS: A total of 229 patients with cervical carcinoma were randomized to morning (8:00-10:00 AM) and evening (6:00-8:00 PM) arms. The incidence of mucositis in the 2 arms was assessed and reported in terms of various grades of diarrhea. RESULTS: Overall (grade I-IV) as well as higher grade (III and IV) diarrhea was found to be significantly increased in the morning arm as compared with the evening arm (overall: 87.39 % vs 68.18 %, P < .01; higher grade: 14.29% vs 5.45%, P < .05). Other radiation-induced toxicity was also higher in the morning arm, but its occurrence in the 2 arms did not differ significantly (13.45% vs 12.73%, P > .05). After completion of treatment, patients' response to radiation in the 2 arms was similar (P > .05). CONCLUSIONS: The significant difference in the incidence of higher grade diarrhea between the morning and evening arms is indirect evidence of the influence of circadian rhythm on the intestinal mucosa of the human intestine. This knowledge may facilitate treating patients with decreased toxicity to the intestinal mucosa.