S. Cammelli

Radiobiologic response of medulloblastoma cell lines: involvement of β-catenin?

Medulloblastoma (MB) is the most common brain malignancy in children. Whole neural axis irradiation is the treatment of choice, but it often results in long-term neurocognitive and developmental impairment. Only insights into MB biology will lead to improved therapeutic outcome. Wingless (WNT) signalling deregulation occurs in up to 25% of sporadic tumors, but the specific role of nuclear β-catenin and its involvement in the radioresponse remains unsettled. Therefore we studied the γ-radiation response of two MB cell lines from cellular and molecular points of view. Our data show that the p53 wild-type cell line is more sensitive to ionizing radiations (IR) than the p53 mutated line, but apoptosis is also induced in p53-mutated cells, suggesting an alternative p53-independent mechanism. In addition, this study is the first to demonstrate that γ-rays trigger the WNT system in our in vitro models. Further studies are required to test if this could explain the radiosensitivity of MB and the favorable prognostic value of nuclear β-catenin in this tumor.

Volumetric modulated arc therapy for treatment of solid tumors: current insights

Aim This article discusses the current use of volumetric modulated arc therapy (VMAT) techniques in clinical practice and reviews the available data from clinical outcome studies in different clinical settings. An overview of available literature about clinical outcomes with VMAT stereotactic/radiosurgical treatment is also reported. Materials and methods All published manuscripts reporting the use of VMAT in a clinical setting from 2009 to November 2016 were identified. The search was carried out in December 2016 using the National Library of Medicine (PubMed/Medline). The following words were searched: “volumetric arc therapy”[All Fields] OR “vmat”[All Fields] OR “rapidarc”[All Fields], AND “radiotherapy”[All Fields] AND “Clinical Trial”[All Fields]. Results Overall, 37 studies (21 prospective and 16 retrospective) fulfilling inclusion criteria and thus included in the review evaluated 2,029 patients treated with VMAT; of these patients, ~30.8% had genitourinary (GU) tumors (81% prostate, 19% endometrial), 26.2% head-and-neck cancer (H&NC), 13.9% oligometastases, 11.2% had anorectal cancer, 10.6% thoracic neoplasms (81% breast, 19% lung), and 7.0% brain metastases (BMs). Six different clinical scenarios for VMAT use were identified: 1) BMs, 2) H&NC, 3) thoracic neoplasms, 4) GU cancer, 5) anorectal tumor, and 6) stereotactic body radiation therapy (SBRT) performed by VMAT technique in the oligometastatic patient setting. Conclusion The literature addressing the clinical appropriateness of VMAT is scarce. Current literature suggests that VMAT, especially when used as simultaneous integrated boost or SBRT strategy, is an effective safe modality for all cancer types.

Short course accelerated radiation therapy (SHARON) in palliative treatment of advanced solid cancer in older patients: A pooled analysis

OBJECTIVES To evaluate the efficacy and safety of a conformal Short Course Accelerated Radiation therapy (SHARON) for symptomatic palliation of locally advanced or metastatic cancers in older patients. MATERIALS AND METHODS This is a pooled analysis on patients aged ≥80 years selected between subjects enrolled in 3 phase I-II studies on a short course palliative treatment of advanced or metastatic cancer. The primary endpoint was to evaluate the symptoms response rate produced by accelerated radiotherapy delivered in 4 total fractions in twice a day. Total dose ranged between 14 Gy and 20 Gy while dose/fraction between 3.5 and 5 Gy. RESULTS A total of 48 patients were included in this analysis. Twenty-six patients (54.2%) had advanced primary or metastatic head and neck tumors, 11 (22.9%) locally advanced or metastatic thoracic cancers, 11 (22.9%) complicated bone metastases. The majority of patients presented pain (60.4%). With a median follow-up time of 5.5 months, no G4 acute and late toxicities were recorded. The overall palliative response rate was 91.7% with a median duration of palliation of 4 months. CONCLUSION Short course accelerated radiotherapy in locally advanced or metastatic cancers is effective in terms of symptom relief and well tolerated even in older patients.

Intensity modulated radiation therapy for breast cancer: current perspectives

Background Owing to highly conformed dose distribution, intensity modulated radiation therapy (IMRT) has the potential to improve treatment results of radiotherapy (RT). Postoperative RT is a standard adjuvant treatment in conservative treatment of breast cancer (BC). The aim of this review is to analyze available evidence from randomized controlled trials (RCTs) on IMRT in BC, particularly in terms of reduction of side effects. Methods A literature search of the bibliographic database PubMed, from January 1990 through November 2016, was performed. Only RCTs published in English were included. Results Ten articles reporting data from 5 RCTs fulfilled the selection criteria and were included in our review. Three out of 5 studies enrolled only selected patients in terms of increased risk of toxicity. Three studies compared IMRT with standard tangential RT. One study compared the results of IMRT in the supine versus the prone position, and one study compared standard treatment with accelerated partial breast IMRT. Three studies reported reduced acute and/or late toxicity using IMRT compared with standard RT. No study reported improved quality of life. Conclusion IMRT seems able to reduce toxicity in selected patients treated with postoperative RT for BC. Further analyses are needed to better define patients who are candidates for this treatment modality.

Adjuvant radiotherapy with brachytherapy boost in soft tissue sarcomas

Purpose The standard primary treatment for soft tissue sarcoma (STS) is a wide surgical resection, preceded or followed by radiotherapy. Purpose of this retrospective study was to assess the efficacy of perioperative brachytherapy (BRT) plus postoperative external beam radiation therapy (EBRT) in patients with intermediate-high risk STS. Material and methods BRT delivered dose was 20 Gy. External beam radiation therapy was delivered with 3D-technique using multiple beams. The prescribed dose was 46 Gy to the PTV. Neoadjuvant and adjuvant chemotherapy (CHT) was used in patients with potentially chemosensitive histological subtypes. The primary aim of the study was to analyze overall survival (OS) and local control (LC) in a large patient population treated with surgery, perioperative BRT, and adjuvant EBRT ± CHT. Secondary objective was to identify prognostic factors for patients outcome in terms of LC, disease-free survival (DFS), and OS. Results From 2000 to 2011, 107 patients presenting 2-3 grade (FNLCC) primary or recurrent STS were treated with surgery, perioperative BRT, and adjuvant EBRT ± CHT. Five-year LC and OS were 80.9% and 87.4%, respectively. At univariate analysis, a higher LC was recorded in primary vs. recurrent tumors (p = 0.015), and in lower limb tumors vs. other sites (p = 0.027). An improved DFS was recorded in patients with lower limb tumors vs. other sites (p = 0.034). Conclusions The combination of BRT and EBRT was able to achieve satisfactory results even in a patients population with intermediate-high risk STS. Patients with recurrent or other than lower limb sited tumors show a worse LC.

Prognostic Impact of Presurgical CA19-9 Level in Pancreatic Adenocarcinoma: A Pooled Analysis

BACKGROUND: Presurgical carbohydrate antigen 19-9 (CA19-9) level predicts overall survival (OS) in resected pancreatic adenocarcinoma (PaC). The aim of this pooled analysis was to evaluate if presurgical CA19-9 level can also predict local control (LC) and distant metastasis-free survival (DMFS). METHODS: Seven hundred patients with PaC from eight institutions who underwent surgical resection ± adjuvant treatment between 2000 and 2014 were analyzed. Patients were divided based on four presurgical CA19-9 level cutoffs (5, 37, 100, 353 U/ml). Weibull regression model to identify independent predictors of OS on 404 patients with complete information was fitted. RESULTS: Median follow-up was 17 months (range: 2-225 months). Univariate analysis showed a better prognosis in pT1-2, pN0, diameter <30 mm, or grade 1 tumors and in patients undergoing R0 resection, distal pancreatectomy, or adjuvant chemotherapy and with lower CA19-9 levels. Five-year OS, LC, and DMFS were as follows: CA19-9 <5.0: 5.7%, 47.2%, 17.0%; CA19-9 5.1-37.0: 37.9%, 63.3%, 46.0%; CA19-9 37.1-100.0: 27.1%, 59.4%, 39.0%; CA19-9 100.1-353.0: 17.4%, 43.4%, 26.7%; CA19-9 >353.1: 10.9%, 50.2%, and 23.4%, respectively. At multivariate analysis, CA19-9 >100 and <353 level (P=.002), CA19-9 ≥353.1 (P<.001) level, G3 tumor (P=.002), and tumor diameter >30 mm (P<.001) correlated with worse OS. Patients treated with postoperative chemoradiation doses >50.0 Gy showed improved OS (P<.001). CONCLUSION: Presurgical CA19-9 predicts both OS and pattern of failure. Therefore, CA19-9 should be included in predictive models in order to customize treatments based on prognostic factors. Moreover, future studies should stratify patients according to presurgical CA19-9 level.

Policies for reirradiation of recurrent high-grade gliomas: a survey among Italian radiation oncologists

Purpose: To assess the contribution of Italian radiation oncologists in the current management of recurrent high-grade gliomas (HGG), focusing on a reirradiation (reRT) approach. Methods: In 2015, the Reirradiation and the Central Nervous System Study Groups on behalf of the Italian Association of Radiation Oncology (AIRO) proposed a survey. All Italian radiation oncologists were individually invited to complete an online questionnaire regarding their clinical management of recurrent HGG, focusing on a reRT approach. Results: A total of 37 of 210 questionnaires were returned (18% of all centers): 16 (43%) from nonacademic hospitals, 14 (38%) from academic hospitals, 5 (13%) from private institutions, and 2 (6%) from hadron therapy centers. The majority of responding centers (59%) treated ≤5 cases per year. Performance status at the time of recurrence, along with a target diameter <5 cm and an interval from primary radiation ≥6 months, were the prevalent predictive factors considered for reRT. Sixty percent of reirradiated patients had already received a salvage therapy, either chemotherapy (40%) or reoperation (20%). The most common approach for reRT was fractionated stereotactic radiotherapy to a mean (photon) dose of 41.6 Gy. Conclusions: Although there were wide variations in the clinical practice of reRT across the 37 centers, the core activities were reasonably consistent. These findings provide a basis for encouraging a national collaborative study to develop, implement, and monitor the use of reRT in this challenging clinical setting.

Feasibility of 2D‑conformal radiotherapy for pancreatic carcinoma

The purpose of the present study was to propose an optimized 2D technique (2D-conformal) for radiotherapy (RT) of pancreatic cancer (CaP). This technique is based on double simulation which resolves the problems of radiographic image distortion. Five patients with locally advanced CaP were identified and enrolled. Treatment planning was simulated in 3 different ways: Two dimensional-standard (2D-SRT), 2D-conformal (2D-CRT), and three dimensional-conformal (3D-CRT) techniques for 10 MV LINAC. Simulation for a cobalt machine was also performed using only the 2D techniques. 2D-SRT technique was planned with fields definition based on anatomical landmarks (bone and duodenum). 3D-CRT was planned with standard virtual simulation technique, and 3D dose evaluation and optimization. 2D-CRT technique was based on manual information transfer from a diagnostic CT-scan to simulation radiograms. To eliminate the X-ray image distortion, a double simulation was employed and the profile of the GTV was delineated on radiographs bearing the simulator isocenter into the target center. Concerning target irradiation of either LINAC (10 MV) or cobalt source, the PTV constraints (ICRU 62) were met in all patients (Dmin >95%, Dmax <107%) with all techniques (2D-SRT, 3D-CRT, 2D-CRT). For organs at risk irradiation, in terms of Dmax to both duodenum and spinal cord, similar results were recorded with all techniques using the LINAC (10 MV). Liver and kidneys Dmean gradually improved from 2D-SRT to 2D-CRT and 3D-CRT. The 2D-CRT compared to 2D-SRT technique, halved the average dose to the liver and reduced to about 1/3 the average dose to the kidneys. With the cobalt source, using the 2D-CRT produced a reduction of Dmean to the kidneys (median from 30.7 to 16.9%) and liver (median from 33.4 to 22.3%) compared to 2D-SRT. This analysis showed better planning results in RT treatment of CaP while using a 2D-CRT compared to 2D-SRT technique and therefore presents an example for optimized 2D RT use.

Definition of fields margins for palliative radiotherapy of pancreatic carcinoma

The present study aimed to provide practical guidelines for palliative treatment of advanced carcinoma of the pancreas (CAP) with the 2D technique. Fifteen patients with locally advanced CAP consecutively treated with radiation therapy at the Radiation Oncology Center, Research and Care Foundation ‘Giovanni Paolo II’ (Campobasso, Italy) underwent computed tomography simulation in supine position. Definition of the clinical target volume (CTV) included the head and body of the pancreas, and the retropancreatic space. The planning target volume was defined by adding a margin of 14 mm to the CTV in the cranio-caudal direction and of 11 mm in radial direction. For each patient, 3 treatment plans were calculated using a cobalt source, 6 MV photons and 15 MV photons (box technique). Beams were drawn using the primary collimators without using multileaf collimators, and progressively optimized in order to respect the minimum dose (Dmin>90%) constraint. Once the final plan was achieved, distances of the fields edges from a set of reference points (bony or duodenal landmarks) were measured. Using this technique, 15 anterior-posterior and postero-anterior (AP-PA) beams and 15 pairs of lateral-lateral (LL) beams were defined for the different patients. Finally, the single minimal AP-PA and LL beams able to include the 15 sets of AP-PA and LL beams were defined. The results of this analysis are reported in tabular form. Guidelines are provided for treatment based on cobalt unit or Linear accelerator (both 6 and 15 MV photons). This study provides information regarding field size and position. A dosimetric study has been planned to identify the dose to be administered with this technique taking into account current dose-volume constraints.

Stereotactic radiotherapy of pancreatic cancer: a systematic review on pain relief.

Locally advanced pancreatic carcinoma (LAPC) has a poor prognosis and the purpose of treatment is survival prolongation and symptom palliation. Radiotherapy has been reported to reduce pain in LAPC. Stereotactic RT (SBRT) is considered as an emerging radiotherapy technique able to achieve high local control rates with acceptable toxicity. However, its role in pain palliation is not clear. To review the impact on pain relief with SBRT in LAPC patients, a literature search was performed on PubMed, Scopus, and Embase (January 2000–December 2017) for prospective and retrospective articles published in English. Fourteen studies (479 patients) reporting the effect of SBRT on pain relief were finally included in this analysis. SBRT was delivered with both standard and/or robotic linear accelerators. The median prescribed SBRT doses ranged from 16.5 to 45 Gy (median: 27.8 Gy), and the number of fractions ranged from 1 to 6 (median: 3.5). Twelve of the 14 studies reported the percentage of pain relief (in patients with pain at presentation) with a global overall response rate (complete and partial response) of 84.9% (95% CI, 75.8%–91.5%), with high heterogeneity (Q2 test: P<0.001; I2=83.63%). All studies reported toxicity data. Acute and late toxicity (grade ≥3) rates were 3.3%–18.0% and 6.0%–8.2%, respectively. Reported gastrointestinal side effects were duodenal obstruction/ulcer, small bowel obstruction, duodenal bleeding, hemorrhage, and gastric perforation. SBRT achieves pain relief in most patients with pancreatic cancer with an acceptable gastrointestinal toxicity rate. Further prospective studies are needed to define optimal dose/fractionation and the best systemic therapies modality integration to reduce toxicity and improve the palliative outcome. Finally, the quality of life and, particularly, pain control should be considered as an endpoint in all future trials on this emerging treatment technique.