N. Rodriguez de Dios

Risk factors of local relapse in breast cancer.: the importance of age

Purpose:The objective of the present analysis is to know what risk factors affect local relapse in breast cancer.Methods and materials:A total of 1165 patients diagnosed with early breast cancer were included. Boost dose was modulated in the presence of risk factors. Patients with one risk factor received a boost of 10 Gy, while 20 Gy was administered in those with two risk factors.Results:Median follow-up was of 60 months. Mean age of patients was 56.7±10.8 years. Local risk factors were present in 82.8% of patients. The probability of remaining free of local recurrence at 5 and 10 years is 97.7% (CI 95%: 96.7–98.7) and 94.5% (CI 95%: 92.1–96.9). Only age showed an impact in local relapse on multivariate analysis. Patients 40 years or younger had a relative risk of local relapse of 5.27 and patients 41–50 of 3.7 with respect to patients older than 50 years.Conclusion:Patients 40 years or younger have a higher risk of local failure than older patients. Other risk factors such as tumour size, intraductal carcinoma or margin status could be masked by an increase of radiation dose.

Targeted therapy combined with radiotherapy in non-small-cell lung cancer: a review of the Oncologic Group for the Study of Lung Cancer (Spanish Radiation Oncology Society)

In recent years, major advances in our understanding of the molecular biology of lung cancer, together with significant improvements in radiotherapy technologies, have revolutionized the treatment of non-small cell lung cancer (NSCLC). This has led to the development of new therapies that target molecular mutations specific to each tumor type, acting on the cell surface antigens or intracellular signaling pathways, or directly affecting cell survival. At the same time, ablative dose radiotherapy can be delivered safely in the context of metastatic disease. In this article, the GOECP/SEOR (Oncological Group for Study of Lung Cancer/Spanish Society of Radiation Oncology) reviews the role of new targeted therapies used in combination with radiotherapy in patients with locally advanced (stage III) NSCLC and in patients with advanced, metastatic (stage IV) NSCLC.

Recent developments in radiotherapy for small-cell lung cancer: a review by the Oncologic Group for the Study of Lung Cancer (Spanish Radiation Oncology Society)

Small-cell lung cancer (SCLC) accounts for 13% of all lung tumours. The standard treatment in patients with limited-stage disease is radiotherapy combined with chemotherapy. In extensive SCLC, the importance of consolidation thoracic radiotherapy in patients with a good treatment response has become increasingly recognized. In both limited and extensive disease, prophylactic cranial irradiation is recommended in patients who respond to treatment. New therapeutic approaches such as immunotherapy are being increasingly incorporated into the treatment of SCLC, although more slowly than in non-small cell lung cancer (NSCLC). Diverse radiation dose and fractionation schemes, administered in varying combinations with these new drugs, are being investigated. In the present study we review and update the role of radiotherapy in the treatment of SCLC. We also discuss the main clinical trials currently underway in order to identify future trends.

Evidence-based recommendations of postoperative radiotherapy in lung cancer from Oncologic Group for the Study of Lung Cancer (Spanish Radiation Oncology Society)

Locally advanced non-small cell lung cancer (NSCLC) is a diversified illness in which postoperative radiation therapy (PORT) for complete resection with positive hiliar (pN1) and/or mediastinal (pN2) lymph nodes is controversial. Although several studies have shown that PORT has beneficial effects, randomized trials are needed to demonstrate its impact on overall survival. In this review, the Spanish Radiation Oncology Group for Lung Cancer describes the most relevant literature on PORT in NSCLC patients stage pN1–2. In addition, we have outlined the current recommendations of different national and international clinical guidelines and have also specified practical issues regarding treatment volume definition, doses and fractionation.

Neoadjuvant treatment followed by surgery versus definitive chemoradiation in stage IIIA-N2 non-small-cell lung cancer: A multi-institutional study by the oncologic group for the study of lung cancer (Spanish Radiation Oncology Society)

OBJECTIVES The role of surgery in stage IIIA-N2 non-small cell lung cancer (NSCLC) is an actively debated in oncology. To evaluate the value of surgery in this patient population, we conducted a multi-institutional retrospective study comparing neoadjuvant chemoradiotherapy or chemotherapy plus surgery (CRTS) to definitive chemoradiotherapy (dCRT). MATERIAL AND METHODS A total of 247 patients with potentially resectable stage T1-T3N2M0 NSCLC treated with either CRTS or dCRT between January 2005 and December 2014 at 15 hospitals in Spain were identified. A centralized review was performed to ensure resectability. A propensity score matched analysis was carried out to balance patient and tumor characteristics (n = 78 per group). RESULTS Of the 247 patients, 118 were treated with CRTS and 129 with dCRT. In the CRTS group, 62 patients (52.5%) received neoadjuvant CRT and 56 (47.4%) neoadjuvant chemotherapy. Surgery consisted of either lobectomy (97 patients; 82.2%) or pneumonectomy (21 patients; 17.8%). In the matched samples, median overall survival (OS; 56 vs 29 months, log-rank p = .002) and progression-free survival (PFS; 46 vs 15 months, log-rank p < 0.001) were significantly higher in the CRTS group. This survival advantage for CRTS was maintained in the subset comparison between the lobectomy subgroup versus dCRT (OS: 57 vs 29 months, p < 0.001; PFS: 46 vs 15 months, p < 0.001), but not in the comparison between the pneumonectomy subgroup and dCRT. CONCLUSION The findings reported here indicate that neoadjuvant chemotherapy or chemoradiotherapy followed by surgery (preferably lobectomy) yields better OS and PFS than definitive chemoradiotherapy in patients with resectable stage IIIA-N2 NSCLC.

EP-1221: Accelerated hypofractionated three-dimensional conformal radiation therapy (AHRT) for NSCLC

Results: The main result was the reduction in primary and nodal volumes due to better definition of lung mass and nearby lung Collapse , the latter could be easily defined in 14 cases on the DW-MRI vs. 7 cases only by CT scans (P=0.016). Median GTV total (sum of 1ry and nodal GTV), on MRI Diffusion compared to that on the CT scan was 354 and 386 cm3 respectively (P= 0.009). In 15 cases, a mean decrease in the GTV total of 34% ±56% (median, 9%; range, 0.232.5%) by using DW-MRI. only in three other cases a mean increase in the GTV total of 12.7% ±14.9% (median, 9.7%; range, 0.4221%). was found. The median PTVs on the CT scans vs. the MRI Diffusion were 1623 (range, 493–2965 cm3) & 1419 (range, 542–3158 cm3) respectively which was statistically non significant (P= 0.391).

EP-1594: Evaluation of toxicity in postoperative endometrial brachytherapy

Purpose/Objective: The purpose of this study is to evaluate our first experience with 3D image-guided breast brachytherapy (BT) and to compare dose distribution parameters between Paris dosimetry treatment plans and image-based treatment plans. Materials and Methods: First, 49 consecutive breast cancer patients treated with high dose rate (HDR) interstitial brachytherapy were selected for the study. All patients received 10Gy boost dose after whole breast irradiation. Every patient underwent computed tomography and the planning target volume (PTV) and organs at risk (OAR) were outlined. Two treatment plans were created for every patient. First, based on a Paris dosimetry system (PDS), and the second one, imaged-based plan with graphical optimization (OPT). The reference isodose in PDS implants was 85%, whereas in OPT plans the isodose was chosen to obtain proper target coverage. Dose and volume parameters (D90, D100, V90, V100), dose at OARs, total reference air kerma (TRAK) and quality assurance parameters: dose nonuniformity ratio (DNR), dose homogeneity index (DHI), external volume index (EI) and conformal index (COIN) were used for a comparison of both plans. Results: One-, two-, three-plane implants were used. The mean number of catheters was 7, but the mean for first 20 patients was 5 and almost 9 catheters for the next 29 patients. The volume of PTV ranged from 13,6 cm to 163,4 cm (mean: 58,2 cm). The mean value of isodose selected for prescribing the dose for OPT plans was 73%. The mean D90 was 88,2% and 105,8%, the D100 was 59,8% and 75,7%, the V90 was 88,6% and 98,1%, the V100 was 79,9% and 98,9% and the TRAK was 0,00375 Gym and 0,00439 Gym for the PDS and OPT plans respectively. The mean DNR was 0,29 and 0,42, the DHI was 0,71 and 0,58, the EI was 0,15 and 0,23 and the COIN was 0,68 and 0,76 respectively. All differences are statistically significant. Conclusions: The target coverage in image-guided plans (OPT) was significantly higher than in plans based on Paris dosimetry system (PDS), but the dose homogeneity was worse. Also value of TRAK increased because of change of prescribing isodose. Our first experience proved, that more number of needles allows to obtain better dose distribution. Electronic Poster: Brachytherapy track: Gynaecology