To evaluate a knowledge based planning model for RapidPlan (RP) generated for advanced head and neck cancer (HNC) patient treatments, as well its ability to possibly improve the clinical plan quality. The stability of the model was assessed also for a different beam geometry, different dose fractionation and different management of bilateral structures (parotids). Dosimetric and geometric data from plans of 83 patients presenting HNC were selected for the model training. All the plans used volumetric modulated arc therapy (VMAT, RapidArc) to treat two targets at dose levels of 69.96 and 54.45 Gy in 33 fractions with simultaneous integrated boost. Two models were generated, the first separating the ipsi- and contra-lateral parotids, while the second associating the two parotids to a single structure for training. The optimization objectives were adjusted to the final model to better translate the institutional planning and dosimetric strategies and trade-offs. The models were validated on 20 HNC patients, comparing the RP generated plans and the clinical plans. RP generated plans were also compared between the clinical beam arrangement and a simpler geometry, as well as for a different fractionation scheme. RP improved significantly the clinical plan quality, with a reduction of 2 Gy, 5 Gy, and 10 Gy of the mean parotid, oral cavity and laryngeal doses, respectively. A simpler beam geometry was deteriorating the plan quality, but in a small amount, keeping a significant improvement relative to the clinical plan. The two models, with one or two parotid structures, showed very similar results. NTCP evaluations indicated the possibility of improving (NTCP decreasing of about 7%) the toxicity profile when using the RP solution. The HNC RP model showed improved plan quality and planning stability for beam geometry and fractionation. An adequate choice of the objectives in the model is necessary for the trade-offs strategies.

To appraise the ability of a radiomics based analysis to predict local response and overall survival for patients with hepatocellular carcinoma. A set of 138 consecutive patients (112 males and 26 females, median age 66 years) presented with Barcelona Clinic Liver Cancer (BCLC) stage A to C were retrospectively studied. For a subset of these patients (106) complete information about treatment outcome, namely local control, was available. Radiomic features were computed for the clinical target volume. A total of 35 features were extracted and analyzed. Univariate analysis was used to identify clinical and radiomics significant features. Multivariate models by Cox-regression hazards model were built for local control and survival outcome. Models were evaluated by area under the curve (AUC) of receiver operating characteristic (ROC) curve. For the LC analysis, two models selecting two groups of uncorrelated features were analyzes while one single model was built for the OS analysis. The univariate analysis lead to the identification of 15 significant radiomics features but the analysis of cross correlation showed several cross related covariates. The un-correlated variables were used to build two separate models; both resulted into a single significant radiomic covariate: model-1: energy p < 0.05, AUC of ROC 0.6659, C.I.: 0.5585–0.7732; model-2: GLNU p < 0.05, AUC 0.6396, C.I.:0.5266–0.7526. The univariate analysis for covariates significant with respect to local control resulted in 9 clinical and 13 radiomics features with multiple and complex cross-correlations. After elastic net regularization, the most significant covariates were compacity and BCLC stage, with only compacity significant to Cox model fitting (Cox model likelihood ratio test p < 0.0001, compacity p < 0.00001; AUC of the model is 0.8014 (C.I. = 0.7232–0.8797)). A robust radiomic signature, made by one single feature was finally identified. A validation phases, based on independent set of patients is scheduled to be performed to confirm the results.

Objective: Breast planning with volumetric modulated arc therapy (VMAT) has been explored, especially for left-sided breast treatments, with the primary intent of lowering the heart dose and improving target dose homogeneity. As a trade-off, larger healthy tissue volumes would receive low dose levels, with the potential risk of increasing late toxicities and secondary cancer induction, although no clinical data are available today to confirm the risk level. The scope of this work is to explore the dosimetric trade-offs using two different VMAT plans. Methods: Two planning strategies for dual-partial-arc VMAT, RA_avoid and RA_full, with and without avoidance sectors, were explored in a cohort of 20 patients, for whole left breast irradiation for 40.05 Gy to the mean target dose in 15 fractions. Common dose objectives included a stringent dose homogeneity, mean dose to the heart <5 Gy, ipsilateral lung (I lung) <8 Gy, contralateral lung (C lung) <2 Gy and contralateral breast (C breast) <3 Gy. Results: RA_full showed a better dose conformity, lower high-dose spillage in the healthy tissue and lower skin dose. RA_avoid presented a reduction of the mean doses for all critical structures: 51% to the heart, 12% to the I lung, 81% to the C lung and 73% to the C breast. All differences were significant with p < 0.0001. Conclusion: The adaptation of VMAT options to planning objectives reduced significantly the healthy tissue dose levels at the price of some high-dose spillage. Evaluation of the trade-offs for application to the different critical structures should drive in improving the usage of the VMAT technique for breast cancer treatment. Advances in knowledge: Different planning strategies in the same VMAT technique could give significant variations in dose distributions. The choice of the trade-offs would affect the possible future late toxicity and secondary cancer induction risk.

Background: Hepatocellular carcinoma (HCC) is the most frequent liver malignancy and a leading cause of cancer death in the world. In unresectable HCC patients, transcatheter arterial (chemo-) embolization (TAE/TACE) has shown a disease response in 15–55% of cases. Though multiple TAE/TACE courses can be administered in principle, Stereotactic Body Radiotherapy (SBRT) has emerged as an alternative option in the case of local relapse following multiple TAE/TACE courses. Methods: This is a single-center, prospective, randomized, controlled, parallel-group superiority trial of SBRT versus standard TAE/TACE for the curative treatment of the intermediate stage of HCC after an incomplete response following TAE/TACE (NCT02323360). The primary endpoint is 1-year local control (LC): 18 events were needed to assess a 45% difference (HR: 0.18) in favor of SBRT. The secondary endpoints are 1-year Progression-Free Survival (PFS), Distant Recurrence-Free Survival (DRFS), Overall Survival (OS) and the incidence of acute and late complications. Results: At the time of the final analysis, 40 patients were enrolled, 19 (49%) in the TAE/TACE arm and 21 (51%) in the SBRT arm. The trial was prematurely closed due to slow accrual. The 1- and 2-year LC rates were 57% and 36%. The use of SBRT resulted in superior LC as compared to TAE/TACE rechallenge (median not reached versus 8 months, p = 0.0002). PFS was 29% and 16% at 1 and 2 years, respectively. OS was 86% and 62% at 1 year and 2 years, respectively. In the TAE arm, PFS was 13% and 6% at 1 and 2 years, respectively. In the SBRT arm, at 1 and 2 years, PFS was 37% and 21%, respectively. OS at 1 and 2 years was 75% and 64% in the SBRT arm and 95% and 57% in the TACE arm, respectively. No grade >3 toxicity was recorded. Conclusions: SBRT is an effective treatment option in patients affected by inoperable HCC experiencing an incomplete response following ≥1 cycle of TAE/TAC.

To report toxicity and early clinical outcomes of hypofractionated simultaneous integrated boost (SIB) approach with Volumetric Modulated Arc Therapy (VMAT) as adjuvant treatment after breast-conserving surgery. Patients presenting early-stage breast cancer were enrolled in a phase II trial. Eligibility criteria: age > 18 years old, invasive cancer or ductal carcinoma in situ (DCIS), Stage I-II (T < 3 cm and N ≤ 3), breast-conserving surgery without oncoplastic reconstruction. Any systemic therapy was allowed in neoadjuvant or adjuvant setting. All patients underwent VMAT-SIB technique to irradiate the whole breast and the tumor bed. Doses to whole breast and surgical bed were 40.5 Gy and 48 Gy, respectively, delivered in 15 fractions over 3 weeks. Acute and late skin toxicities were recorded. Cosmetic outcome was assessed as excellent/good or fair/poor. The present study focused on results of a cohort of 144 patients with a minimum follow-up of 24 months (median 37, range 24–55 months). Median age was 62 years old (range 30–88). All patients had an invasive carcinoma (no patients with DCIS were present in this subset). At one year, the highest reported skin toxicity was G1, in 14 % of the patients; this data dropped to 4 % at the last follow-up, after more than 2 years. Breast pain was recorded in 21.6 % of the patients 6 months after treatment, while it was present in 3.5 % of the patients at the last follow-up, showing a significant improvement with time. Correlation between liponecrosis and boost target volume was found not significant. Breast pain was correlated with breast volume. No pulmonary or cardiological toxicities were recorded. After an early evaluation of clinical outcomes, only one case presented disease relapse, as liver metastases. The 3-week VMAT-SIB course as adjuvant treatment after breast-conserving surgery showed to be well tolerated and was associated with optimal local control. Long-term follow-up data are needed to assess late toxicity and clinical outcomes.