Background: Aim is to find correlation between 2D-gamma passing rate and 3D-DVHbased pre-treatment patient-specific quality assurance. Materials and Methods: 21 head and neck and 21 pelvis patients, treated with volumetric modulated arc therapy (VMAT) were selected for this study. All patients were planned with Elekta VersaHD linear accelerator using Monaco (5.11) treatment planning system. 2D-planar dose measurements were performed with IBA-I'matriXX evolution detector-array using MyQA-Patients software. For 2D-Gamma index evaluation, 3%/3mm and 2%/2mm criteria were used. 3D-dose measurements were performed using the IBA-COMPASS system. For 3D measurement, Monaco and COMPASS doses were compared in terms of percentage dose differences to PTV and organs at risk. For PTV D95, D2, and D50 (dose received by 95%, 2%, and 50% volume), similarly for OARs D2 and D50 were noted. 3D Gamma index was also noted. Correlation coefficient and its corresponding two-tailed p-value (<= 0.05, for statistically significant) were calculated for 2D-gamma passing rate and 3D Gamma index & percentage dose differences of 3D-DVH based metrics (Monaco calculated versus COMPASS measured). Strength of correlation will be considered weak or strong based on the r -value. Results: 2D-Gamma index passing rate was 98.6 +/- 1.8%, 92.1 +/- 7.1% and 98.5 +/- 1.3%, 93.5 +/- 4.4% for head-neck and pelvis patients (3%/3mm, 2%/2mm criteria) respectively. Percentage dose-differences for PTV D95, D2, D50 for head-neck and pelvis were: 4.22 +/- 2.09%, 4.25 +/- 2.23%, 3.93 +/- 1.59 & 0.60 +/- 1.96%, 1.53 +/- 1.64%, 1.59 +/- 1.20% respectively. Spine and brainstem D2 were 0.84 +/- 6.10%, 0.77 +/- 2.70%, bladder and rectum D50 were 3.75 +/- 3.31%, -2.19 +/- 3.60%. Conclusion: No strong correlation was observed between the 2D Gamma passing rate and 3D measurements.

Insects are considered good bio-indicator due to their cosmopolitan presence, species diversity, habitat diversification and economic importance. They are important part of energy flow being primary herbivore of the food chain. Being a good bio-indicator, they represents different habitat of forest ecosystem. Their presence in any habitat is affected by smallest change in climatic factors like rainfall, temperature, humidity, altitude, Latitude/longitude. Insects carry out multiple roles within the forests i.e. as primary consumer of food chain, as pollinators, as decomposers, and finally as a food sources for other higher organisms. The class insect is the most abundant and diverse group in the phylum Arthropoda and approximately more than 900,000 species has been described till now and yet many more are still unidentified. They constituent more than 70-80% of all the identified animal species and their existence on earth is recorded 35 million years ago with help of fossil specimens. The untouched and fragile landscape of the Himalayas is in ongoing concern about effects of climate change in the region. Insects are poikilothermic in nature and therefore they are highly sensitive to their surrounding climate particularly the temperature. The present study was conducted at three sites i.e. Chanshal (Shimla), Rohtang (Kullu) and Sach (Chamba) area. to assess the impact of these climatic parameters on population, abundance and richness of different insects species along altitudinal gradient in different forest ecosystem ranging from 1500m-4000m amsl. It was observed that there is clear segregation in species as well as population diversity along with altitude gradient, which indicates insect as good indicator of habitat type. Any biotic or abiotic disturbance affects the insect diversity of the habitat. The study will be helpful in developing the conservation plan to restore the diversity in the region.

We assessed the feasibility of ISRT after chemo-immunotherapy in patients with early nodal DLBCL in a single arm phase II trial. The co-primary endpoints were treatment related acute toxicity profile and serial changes in quality of life (QoL) parameters. 28 immunocompetent patients aged 18-70 years with stage I-II nodal DLBCL & ECOG PS 0-3 underwent whole body 18F-FDG-PET/CT scan in RT treatment position apart from standard lymphoma workup. Subsequently, they received chemo-immunotherapy (RCHOP21) for 3-6 cycles [6 cycles in patients with bulk (>7.5 cm) or B symptoms]. Response assessment PET/CT scan was repeated after 3 and 6 cycles. Thereafter they underwent ISRT to a dose of 30.6(in CMR)-36(in PMR) Gy at 1.8 Gy/fraction/day by VMAT technique. The gross tumor was contoured on the baseline PET/CT scan and edited on the electronically fused planning CT scan to form the GTV. To this, a 1.5 cm cranio-caudal expansion was given to generate the CTV. A 5-10 mm site-specific isotropic expansion was given to CTV to form the PTV. Chemotherapy related acute toxicity was assessed by CTCAEv4.0. Acute RT toxicity was assessed by RTOG acute radiation morbidity scoring criteria. QoL (TOI & total scores) was assessed by FACT-LYM questionnaire at baseline (Qol1), at completion of chemotherapy (Qol2) and at 3(Qol3) & 6(Qol4) months after completion of RT. Serial changes in QoL parameters were analyzed by Friedman's test and subsequent pair-wise comparison was done by Wilcoxon signed rank test. After chemo-immunotherapy, 86.96% and 13.04% patients had CMR and PMR respectively. 19 out of 26 (73.08%) assessable patients had grade ¾ hematological toxicities- neutropenia in 18 (69.23%) patients and thrombocytopenia in 1 (3.85%) patient. Only 1 patient had febrile neutropenia. Out of 19 patients who completed ISRT, 9 (47.37%) patients had grade ½ hematological toxicities (commonly anemia & neutropenia) and 18 (94.74%) patients had grade ½ non-hematological toxicities (commonly dermatitis, mucositis & xerostomia). The CMR rate at the end of treatment was 94.44%. 1 patient had PMD 1 month after ISRT (in-field failure). One patient (in CMR) died due to non-cancer related cause. The median follow-up was 11.73 months. The PFS & OS rates at 1 and 2 years were 92.3% & 100% and 92.3% & 91.7% respectively. There were significant changes in both TOI (p-0.007) & total score (p-0.002) at different timepoints- an initial dip in QoL2 due to chemotherapy related toxicities followed by a steady rise in QoL3 & QoL4 due to tumor response and resolution of acute toxicities. Chemo-immunotherapy with R-CHOP regimen followed by ISRT is feasible in patients with stage I-II nodal DLBCL in our setting and leads to acceptable early clinical outcome, favorable acute toxicity profile and quality of life.

Whole Breast Radiotherapy (WBRT) is indicated as adjuvant treatment in the multimodality management of Breast Cancer after Breast Cancer Surgery (BCS). Regional Nodal Irradiation (RNI) improves outcomes in patients with positive nodes after axillary dissection. Hypofractionation in WBRT is equivalent to standard fractionation in terms of long-term outcomes, but the role of hypofractionation in the settings of RNI has not been explored. We prospectively conducted a phase II randomized study comparing Hypofractionation and Standard fractionation in WBRT with RNI to evaluate clinical outcomes, cosmesis and quality of life (QOL) between the two modalities. Women aged ≥ 18 years with breast cancer undergoing BCS and axillary dissection were recruited in the study after Institutional Ethics Committee approval. 52 patients were randomized into two groups, with 26 patients in arm 1 (standard fractionation) WBRT 50Gy/25fraction/5weeks followed by boost 16Gy/8fraction and other 26 patients in arm II (hypofractionation) WBRT 40Gy/15fraction/3 weeks followed by boost 10Gy/4fraction. Contouring was done as per the standard RTOG guidelines. WBRT was planned using forward planning IMRT. Direct or oblique photon fields were used for RNI of SCF/ Axillary region as clinically indicated. Contouring and planning was done on MONACO treatment planning system. Clinical acute toxicity, late toxicity was noted with RTOG acute toxicity criteria. Quality of life (QOL) was assessed with EORTC BR 23 questionnaire. Statistical analysis was done with SPSS v 21 and p-value < 0.05 was considered as significant. All patients received planned allocated treatment and were eligible for analysis. At treatment completion, the Grade II skin toxicity was higher in arm I compared to arm II, with 84% vs 11% (p <0.01), Grade III skin toxicity was not noted in arm II, but present in 3(11%) patients of arm I (p <0.01). The skin toxicity at 6 months was similar at 6 months with only Grade I skin toxicity. At completion of radiation, good cosmesis was noted in 8(32%) patients of arm I and 20(77%) patients of arm II, whereas fair cosmesis was observed in 17 (65%) patients of arm I and 6(23%) patients of arm II. The cosmesis at 6 months post radiation was excellent in 21(80%) patients of arm I and 23(88%) patients of arm II, and good cosmesis was seen in 5(20%) patients of arm I and 3(12%) patients of arm II. The cosmesis improved in both the arms at 6 months, and the results were comparable between the groups. There was no significant difference in subcutaneous toxicity, arm toxicity or lymphedema between the two arms at 3 and 6 months. There was no difference in QOL between two arms at 3 and 6 months. WBRT with RNI is feasible with hypofractionation and it is not associated with decreased clinical outcomes as compared to standard fractionation. Lymphedema was similar with hypofractionation. The clinical acute toxicity, cosmesis and QOL was similar with hypofractionation and standard fractionation.

Post mastectomy Radiation (PMRT) is indicated as adjuvant treatment in the multimodality management of Locally Advanced Breast Cancer (LABC). Three-Dimensional Conformal Radiation (3DCRT) for PMRT is used with tangential fields for better target coverage and sparing of organs at risk (OAR). In comparison, VMAT has the potential to improve the coverage and decrease the OAR doses. We prospectively conducted a phase II randomized study comparing 3DCRT (Arm A) and VMAT (Arm B) in PMRT with regional nodal irradiation (RNI) to evaluate dosimetric and clinical differences between the two modalities. Women aged ≥ 18 years with locally advanced breast cancer undergoing MRM were recruited in the study. Forty patients were accrued after Institutional Ethics Committee approval. Contouring was done as per the standard RTOG guidelines. For 3DCRT, Planning was done with single isocenter technique. Two tangential fields with field in field were used for PTV-CW and AP-PA fields with higher AP weightage were used to cover PTV-RNI. For VMAT, two small partial arcs were used. The dose prescribed was 50 Gy in 25 fractions over 5 weeks. Contouring and planning was done on MONACO treatment planning system. Dosimetric analysis was done and compared between the arms. Clinical acute toxicity, late toxicity was noted with RTOG acute toxicity criteria. Quality of life (QOL) was assessed with EORTC BR 23 questionnaire. Statistical analysis was done with SPSS v 21 with chi square test and p-value < 0.05 was considered as significant. Between Jan 2018 to March 2019, forty patients were accrued in the study and twenty patients were randomized to each arm. All patients received planned allocated treatment and were eligible for analysis. PTV CW coverage was similar in both the arms. PTV RNI V95 coverage were better in VMAT arm (97.8%) than 3DCRT arm (94.5%) (p = <0.001). The ipsilateral lung V5 and V20 was 51.6% and 24.7% for VMAT and 47.1% and 27.8% for 3DCRT (p = 0.0185 and p = 0.167). The thyroid V45 was 51.3% for 3DCRT and 42% for VMAT arm (p = 0.018)]. The heart Dmean for 3DCRT and VMAT was 4.3Gy and 6.5Gy (p = 0.0372). There was no significant difference in skin, subcutaneous, lymphedema or lung toxicity between the two arms at 1, 3, and 6 months. There was no difference in global health status and QOL between two arms at 1, 3, and 6 months. No loco-regional recurrence was noted at 6 months. VMAT provides better coverage to lymph nodes with potential to decrease ipsilateral lung dose. The clinical acute toxicity, late toxicity and QOL was similar with VMAT and 3DCRT. A large prospective trial and longer follow-up is needed to confirm the findings.

Aim: Purpose of study is to validate COMPASS 3D patient specific quality-assurance software with Monaco treatment planning system (TPS) for routine quality assurance. Materials & methods: Purpose is to test the MLC modelling in COMPASS software, using Elekta Express QA package contains eight QA fields as follows (i) 10x10 (ii) 20x20 (iii) 3ABUT (iv) DMLC1 (v) HIMRT (vi) HDMLC(vii) 7SegA (viii) Four L were measured with COMPASS and compared with Monaco TPS. For clinical validation of COMPASS, VMAT plans were created for downloadable contoured structure set of AAPM TG119 cases for energy 6MV using Monaco (5.11) TPS for Versa-HD linear-accelerator and verified by COMPASS (calculated and measured). Results: For express QA check, all beams showed gamma pass-rate above 95% except for FourL field. FourL field Monaco versus COMPASS reconstructed gamma pass-rate was 98.4% but Monaco versus COMPASS computed gamma pass rate was 93.4%. COMPASS computed and measured, TG119 test cases showed good agreement with Monaco TPS, except some higher variation in low dose region. Conclusion: COMPASS measured (reconstructed) and computed results are in good agreement with Monaco TPS, therefore can be used for routine patient-specific quality-assurance. Special consideration has to be taken for superficially located targets.

We intended to assess the feasibility of response adapted whole brain radiation therapy (WBRT) after high dose methotrexate (HDMTX) based chemotherapy in patients of primary CNS lymphoma (PCNSL). We enrolled 24 patients of PCNSL (age 18-80 years, ECOG PS 0-3, HIV seronegative, biopsy proven PCNSL, no significant end organ dysfunction) from 2015-17 in a phase II trial. The patients underwent 5 two-weekly cycles of MPV chemotherapy-methotrexate 3.5 g/m2 IV D1, vincristine 1.4 mg/m2 IV D1 & procarbazine 100 mg/m2 P.O. D1-7(in odd number cycles). Rituximab 375 mg/m2 IV D1 q2weeks was added in 16 patients as per their preference & affordability. Patients with complete response (CR) to induction chemotherapy were given reduced dose WBRT 23.4 Gy/13 fractions/2.5 weeks. Patients with partial response (PR), stable or progressive disease (SD/PD) were given standard dose WBRT 45 Gy/25 fractions/5 weeks. Thereafter 2 cycles of consolidation chemotherapy with cytarabine 3 g/m2/day, IV D1 & D2 were given 1 month apart. Primary endpoints of the study were assessment of response rate & PFS. The secondary endpoints of the study were assessment of OS & toxicity profile. The median age at diagnosis was 50 years & the male:female ratio was 15:9. The ECOG PS was 3, 2 & 1 in 15, 5 & 4 patients, respectively. Out of 20 patients who completed induction chemotherapy, 10 (50%) achieved CR, 9 (45%) had PR & 1 had PD. 2 patients on RMPV regimen died due to sepsis. Induction chemotherapy related grade 3/4 toxicities were anemia in 2, neutropenia in 9(37.5%) & thrombocytopenia in 1 patient. 9 patients received reduced dose & 10 received standard dose WBRT. No RT related grade 3/4 toxicity was reported. Consolidation chemotherapy with cytarabine was given in 16(66.67%) patients. After a median follow-up period of 15.05 months, 5 patients had PD & 11 patients died, causes being PD in 2, sepsis in 2, unknown(PD/toxicity) in 4 & non-cancer related in 3 patients. The estimated median OS was 24.2 months. The median PFS had not been reached. The actuarial rates of 2 year PFS & OS were 61.8% & 54.8% respectively. Four patients in reduced dose WBRT arm had recurrence & 2 of them died of PD, whereas there was no recurrence or cancer related death in standard dose WBRT arm. On univariate analysis of OS, use of RT (p<0.0001), consolidation Ara-C (p=0.013), MVP (vs RMVP) regimen (p=0.019) & no chemotherapy interruption (p=0.03), negative CSF cytology (p=0.003) led to significantly improved outcome. On multivariate analysis of OS, CSF cytology (p=0.026), chemotherapy interruption (p=0.03) & chemotherapy regimen (p=0.015) retained prognostic significance. On univariate analysis of PFS, age≤60 years & use of standard dose WBRT (45 Gy) led to significantly improved outcome (p value=0.004 & 0.04 respectively). In patients with newly diagnosed PCNSL, reduced dose WBRT after complete response to HDMTX based chemotherapy may lead to sub-optimal clinical outcome due to higher risk of recurrence, progression & early death.

Purpose: The aim of this study is to evaluate influence of statistical uncertainty on Monte-Carlo dose calculation of Monaco 5.11 treatment planning system (TPS). Methods: Phantom with contoured C-Shape structure set was downloaded from AAPM website provided with TG119 report. VMAT plan was created for C-Shape test case using Monaco TPS for 6 MV Elekta Versa-HD linear-accelerator. Dose prescription and constraints were as per TG119. After optimizations, C-Shape plan was calculated with different statistical-uncertainty (i) 0.5%, 1.0%, 3.0% and 5.0% per control point and (ii) 0.5%, 1.0%, 3.0% and 5.0% per calculation. Base plan was calculated with 0.5% per control point. Results: Variations in PTV doses for different statistical-uncertainties with respect to 0.5% per control point were within PTV-D95: 82 cGy(1.64%); PTV-D10: 14.8 cGy(0.28%); Core-D10: 3.7 cGy(0.15%). MU required to deliver a plan (920 MU) were observed same with different statistical-uncertainty. Calculation time increases with decrease in statistical-uncertainty due to more number of histories. 2D-Gamma pass rate was ranging from 98.1% to 98.9% for analyzed statistical-uncertainties. Statistical-uncertainty 0.5% per control point showed higher Gamma pass-rate (98.9%). Conclusion: Minor variation (<1.64%) in dose volume parameters was observed with different statistical-uncertainties, whereas Monitor unit remain same. 3.0% per control point and 0.5% per calculation resulted in almost similar results and found optimal with reasonable calculation time in terms of plan quality and delivery accuracy (gamma pass-rate).

22Apr 2017 IMRT AND VMAT COMMISSIONING FOR VERSA HD LINEAR ACCELERATOR USING AAPM TG-119. Seema Sharma MSc Dip , RP Subhash Chander , MD Velliyan Subramani , PhD Pratik Kumar , PhD Suman Bhaskar , MD Sushmita Pathy , MD Sanjay Thulkar , MD N.Gopishankar , PhD Megha Sairem , MSc , Dip. RP Ashish Binjola MSc Dip , RP Dhayanethi N , MSc Pradeep Kumar S. , MSc Priyanka Agarwal , MSc Dip. RP. All India Institute of Medical Sciences, New Delhi, India.

Epithelial myoepithelial carcinoma (EMC) is a rare biphasic tumor of salivary glands with low malignant potential. Although known to occur in submandibular gland and minor salivary glands, its most common location is parotid. Clinical and radiological findings often mimic a benign tumor. Because of rarity of EMC a standard treatment guideline is not yet known. Surgical resection is the most widely used approach. Although it is a low grade tumor, local recurrence rates of 23-50 % have been reported with 25 % chance of distant metastasis. Patients with histo-pathologic markers of aggressive disease should be considered for adjuvant radiotherapy. We report a case of epithelial myoepithelial carcinoma of parotid in a 40 year male that was treated with surgery followed by post-operative radiotherapy.

Radiation-induced liver disease (RILD) or radiation hepatitis is a sub-acute form of liver injury due to radiation. It is one of the most dreaded complications of radiation which prevents radiation dose escalation and re-irradiation for hepatobiliary or upper gastrointestinal malignancies. This complication should be kept in mind whenever a patient is planned for irradiation of these malignancies. Although, incidence of RILD is decreasing due to better knowledge of liver tolerance, improved investigation modalities and modern radiation delivery techniques, treatment options are still limited. In this review article, we have focussed on patho-physiology, risk factors, prevention and management of RILD.

Radiation-induced liver disease (RILD) or radiation hepatitis is a sub-acute form of liver injury due to radiation. It is one of the most dreaded complications of radiation which prevents radiation dose escalation and re-irradiation for hepatobiliary or upper gastrointestinal malignancies. This complication should be kept in mind whenever a patient is planned for irradiation of these malignancies. Although, incidence of RILD is decreasing due to better knowledge of liver tolerance, improved investigation modalities and modern radiation delivery techniques, treatment options are still limited. In this review article, we have focussed on patho-physiology, risk factors, prevention and management of RILD.

PURPOSE To compare the Accelerated Partial Breast Irradiation (APBI) plan with the normalized basal dose points and 5mm box prescription. METHODS Five patients of APBI were planned twice in Oncentra Master planning TPS (Version 4.3) using TG-43 algorithm. The number of catheters for all the patients was 10 to 16 and implant plane 2 to 3. For planning all catheters were reconstructed. Source loading was done as per HR-CTV contoured. The HR-CTV volume range was from 75cc to 182cc. Plans were normalized in two methods. First all plans were normalized on Basal dose points (PlanA) and second all the plan were normalized on 5mm box (PlanB). The prescription dose (PD) was 35Gy in 10 fractions. All the plans were completely based on normalization and without optimization. Plan evaluation was based on certain parameters coverage Index (CI), dose homogeneity index (DHI), conformity index (COIN), over dose volume index (OI). RESULTS The average and median of CI for planA was 0.835 and 0.8154, for planB 0.82 and 0.799 respectively. The median and average of DHI for planA was 0.66 and 0.6062, for planB 0.67 and 0.62 respectively. The range of COIN for planA and planB was from 0.58 to 0.65 respectively. The range of OI was from 0.083 to 0.169 for planA and planB. The treatment time in planA was in average 1.13 times more than planB as V150% of HR_CTV in planA was 4-6% more. The ipsilateral lung was getting 30% of PD which was 0.6% to 3.5%. CONCLUSION Treatment Planning should be individualized based on implants characteristics. Planning with prescription to basal dose points should be preferred to 5mm box prescription, in order to achieve better DHI and less treatment time.

Purpose:To study the influence of clipping PTV from body contour on plan quality and deliverability in build‐up region for superficial target.Methods:Five previously treated patients of post‐operative carcinoma of parotid were re‐planned for IMRT (6MV X‐rays, sliding window technique, five fields and 60Gy/30 fractions) using eclipse treatment planning system (TPS) by keeping dose volume constraints and all other parameters constant, only PTV was clipped from body contour by 0mm, 1mm, 2mm and 3mm respectively. Planned fluence was transferred to previously scanned solid water phantom by placing I'matriXX array at 0.5cm depth (2mm slab+3mm inherent). Fluence was delivered by Varian CL2300C/D linac at 99.5cm source to detector distance. Measured fluence was compared with TPS dose plane using 2D gamma evaluation using 3%/3mm DTA criteria. Total MU (monitor unit) required to deliver a plan was also noted. For plan quality, PTV, maximum‐dose, minimum‐dose, coverage index (CI=PTV volume covered by prescription dose/PTV) and heterogeneity index HI=D5/D95 were analyzed using dose volume histogram (DVH).Results:The Result of gamma function analysis for I'matriXX and TPS were 97.63±1.79%, 97.48±0.99, 98.08±0.89% and 98.01±0.78% at 0.5cm build‐up depth for 0, 1, 2 and 3mm PTV clipping, respectively. I'matriXX measured dose was higher compared to TPS. Total MU required for delivering a plan were 552±61, 503±47, 436±24 and 407±22. Maximum‐dose to PTV was 6635.80±62.01cGy, 6635.80±40.60cGy, 6608.43±51.07cGy and 6564.20±28.51cGy. Similarly, minimum‐dose to PTV was 3306.23±458.56cGy, 3546.57±721.01cGy, 4591.43±298.81cGy and 4861.90±412.40cGy. CI was 0.9347±0.020, 0.9398±0.021, 0.9448±0.022 and 0.9481±0.021. Similarly, HI was 1.089±0.015, 1.084±0.014, 1.078±0.009 and 1.074±0.008 for 0, 1, 2 and 3mm PTV clipping, respectively.Conclusion:Gamma function analysis resulted in almost similar results. However, I'matriXX was overestimating the dose compared to TPS. MU required to deliver a plan decreases with increase in PTV clipping. CI, PTV minimum‐dose and plan homogeneity increases with increase in PTV clipping from skin.