Intraoperative electron radiation therapy after salvage surgery in gynecological cancers and retroperitoneal sarcomas: outcomes and adverse effects.

Background: Salvage surgery is considered an option for isolated recurrences of retroperitoneal and pelvic tumors, in patients who have undergone previous radiotherapy. In order to increase local control intra operative electron radiation therapy (IOERT) can be used in these patients to administer additional radiation dose. We evaluated the outcomes and adverse effects in patients with retroperitoneal sarcoma and gynecologic tumors after salvage surgery and IOERT. Materials and methods: Twenty patients were retrospectively analyzed. Twenty-three IOERT treatments were performed after surgery. Six (30%) were sarcoma and 14 (70%) were gynecological carcinoma. Administered dose depended on previous dose received with external beam radiotherapy (EBRT) and proximity to critical structures. The toxicities were scored using the Common Terminology Criteria for Adverse Events version 4.0. Results: The median age of the patients was 51 years (range 34-70). After a median follow-up of 32 months (range 1-68), in the sarcoma group the local control rate was 66.6%; while in the gynecological group the local control rate was 64.3%. In relation to late toxicity, one patient had a Grade 2 vesicovaginal fistula, and one patient presented Grade 4 enterocolitis and enteric intestinal fistula. Conclusions: IOERT could have a role in the treatment of retroperitoneal sarcomas in primary tumors after EBRT, as it may suggest a benefit in local control or recurrences after surgical resection in those at high risk of microscopic residual disease. The addition of IOERT to salvage resection for isolated recurrence of gynecologic cancers suggest favorable local control in cases with concern for residual microscopic disease.

On the need of in vivo verifications as quality control for intraoperative electron radiotherapy in breast cancer.

INTRODUCTION: Intraoperative electron radiotherapy (IOERT) is a technique aiming to deliver radiotherapy during oncological surgery. In breast IOERT, the applicator and shielding disc placement are correlated with organs at risk (OAR) irradiation, in vivo verification of these parameters is scarcely reported. The aim of our study is to report and analyze possible causes of the misalignment using radiochromic films and compare our results to others reported in the bibliography. METHODS: From November 2019 to April 2023, in vivo verifications were performed for 33 patients. IOERT was performed using a LIAC 10 MeV (Sordina, Italy) electron accelerator. We attached a radiochromic film to the upper side of the polytetrafluoroethylene cover of the shielding disc. The percentage of the irradiation area outside the disc was recorded and various parameters (applicator angulations, prescription depth, tumor location and breast size) were analyzed to find possible correlations. RESULTS: For 29 patients, 20 Gy were prescribed while 10 Gy were prescribed to 4 patients. The average irradiated area outside the disc was 19% (0-56%) corresponding to a surface of 4.5 cm2 (0-17.4 cm2). The applicator of 5 cm was used for most of the patients. The mean prescription depth was 1.4 cm (0.5-2.5 cm). We found no correlation between the analyzed parameters and misalignment. CONCLUSION: This study confirms the presence and magnitude of the misalignments. We strongly recommend in vivo verifications as a quality check during IOERT procedures. The misalignment has no correlation with tumor localization parameters, so the solution could be based on technical improvements of the applicator.

Biological equivalent dose is associated with radiological toxicity after lung stereotactic ablative radiation therapy.

INTRODUCTION: Stereotactic ablative radiation therapy (SABR) is the standard of care for inoperable early-stage non-small-cell lung cancer. Although the probability of grade ≥ II toxicities is low, many patients present radiological subclinical toxicities usually associated with long-term patient management challenges. We evaluated radiological changes and correlated them with the received Biological Equivalent Dose (BED). METHODS: We retrospectively analyzed chest CT scans of 102 patients treated with SABR. An experienced radiologist evaluated the radiation-related changes 6 months and 2 years after SABR. The presence of consolidation, ground-glass opacities, organizing pneumonia pattern, atelectasis and the extent of affected lung were recorded. Dose-volume histograms of the lung healthy tissue were transformed to BED. Clinical parameters such as age, smoking habits, and previous pathologies were registered and correlations between BED and radiological toxicities were drawn. RESULTS: We observed a positive and statistically significant correlation between lung BED over 300 Gy and the presence of organizing pneumonia pattern, the degree of lung affectation and the 2-year prevalence and/or increase of these radiological changes. Radiological changes in patients receiving BED > 300 Gy to a healthy lung volume ≥ 30 cc increased or remained in the 2 years follow-up scan. We found no correlation between radiological changes and the analyzed clinical parameters. CONCLUSIONS: There seems to be a clear correlation between BEDs higher than 300 Gy and radiological changes both short and long term. If confirmed in an independent patient cohort, these findings could lead to the first radiotherapy dose constraints for grade I pulmonary toxicity.

Hypofractionated whole breast irradiation in association with hypofractionated or normofractionated boost to the tumor bed in early breast cancer: tolerance and efficacy analysis.

BACKGROUND: The boost to the tumor bed improves local control in breast cancer and it is an important part of the breast conserving therapy. However, information about the use of a hypofractionated boost is sparse, thus further studies are needed. We conducted a retrospective study with the aim of comparing hypofractionated boost (HB) and normofractionated boost (NB) on skin toxicity and local control. MATERIALS AND METHODS: A total of 96 women with early breast cancer undergoing breast-conserving surgery and hypofractionated whole breast irradiation (WBI) were retrospectively analyzed divided into hypofractionated boost group and conventional fractionation boost group. Forty-nine patients were treated with NB with 16 Gy in 8 fractions and 47 patients were treated with HB with 13.35 Gy in 5 fractions. We examined acute and chronic toxicity with CTCAE version 5. RESULTS: The median follow-up was 49.5 months (26-67). Median age was 57 years (36-82). Sixty-six patients (68.7%) were younger than 60 years at the time of boost and 30 (31.2%) were older than 60 years who received the boost due to poor prognostic factors. No differences were found between the two groups in terms of patient, tumor or treatment characteristics. Grade 2 acute skin toxicity was 6.3% in the NB group and 4.2% in the HB group. Chronic skin induration was 4.2% in the NB group and 1% in the HB group. They did not show grade 3 skin toxicity. There were also no differences in acute or late skin toxicity between the two groups. No local recurrences were evidenced. CONCLUSIONS: Hypofractionated WBI associated with HB treatment is a viable option in the management of conservative breast therapy given the good tolerance and similar local control.

Analgesic effects of low-dose radiotherapy in greater trochanteric pain syndrome: results in a clinical series of 155 patients with recurrent or refractory symptoms.

PURPOSE: This prospective study assessed the effects of low-dose radiotherapy in patients diagnosed with greater trochanteric pain syndrome (GTPS) with recurrent symptoms or refractory to previous conservative measures. METHODS: We evaluated a total of 155 patients (90.3% women, mean age 69 years). Most patients (n = 136) received 10 Gy (1 Gy/day/3 fractions per week on alternate days), but after recommendations of DEGRO guidelines published in 2015, the remaining 19 patients (12.2%) received 6 Gy (1 Gy/day/3 fractions per week on alternate days). RESULTS: At the pre-treatment visit, the mean (standard deviation, SD) visual analog scale (VAS) score was 8), which decreased to 5 (SD 2.2) after 1 month of the end of treatment and to 4 (SD 2.3) after 4 months. An objective symptom response with increased mobility, better sleep quality, and reduction of analgesic medication was found in 56% of patients at 1 month. In 129 patients (83.2%), there was a decrease of at least 1 point in the VAS score, and in 49 patients (29.0%), the VAS score was lower than 3. The mean length of follow-up was 45 months. The probability of maintaining the analgesic response estimated by the Kaplan-Meier method was 53% at 5 years. CONCLUSION: Low dose radiotherapy effectively improved pain in the trochanteric area in most patients with recurrent or refractory GTPS, allowing a reduction in the need for analgesic medications and, more, importantly, better functioning and mobility. Further randomized studies in selected populations of GTPS are needed to define the treatment position of low-dose radiotherapy in this clinical setting.

Limited Liver or Lung Colorectal Cancer Metastases. Systemic Treatment, Surgery, Ablation or SBRT.

The prognosis for oligometastatic colorectal cancer has improved in recent years, mostly because of recent advances in new techniques and approaches to the treatment of oligometastases, including new surgical procedures, better systemic treatments, percutaneous ablation, and stereotactic body radiation therapy (SBRT). There are several factors to consider when deciding on the better approach for each patient: tumor factors (metachronous or synchronous metastases, RAS mutation, BRAF mutation, disease-free interval, size and number of metastases), patient factors (age, frailty, comorbidities, patient preferences), and physicians' factors (local expertise). These advances have presented major challenges and opportunities for oncologic multidisciplinary teams to treat patients with limited liver and lung metastases from colorectal cancer with a curative intention. In this review, we describe the different treatment options in patients with limited liver and lung metastases from colorectal cancer, and the possible combination of three approaches: systemic treatment, surgery, and local ablative treatments.

Pathological response to neoadjuvant therapy with chemotherapy vs chemoradiotherapy in stage III NSCLC-contribution of IASLC recommendations.

BACKGROUND: Neoadjuvant treatment (NT) with chemotherapy (Ch) is a standard option for resectable stage III (N2) NSCLC. Several studies have suggested benefits with the addition of radiotherapy (RT) to NT Ch. The International Association for the Study of Lung Cancer (IASLC) published recommendations for the pathological response (PHR) of NSCLC resection specimens after NT. AIM: To contribute to the IASLC recommendations showing our results of PHR to NT Ch vs NT chemoradiotherapy (ChRT). METHODS: We analyzed 67 consecutive patients with resectable stage III NSCLC with positive mediastinal nodes treated with surgery after NT Ch or NT ChRT between 2013 and 2020. After NT, all patients were evaluated for radiological response (RR) according to Response Evaluation Criteria in Solid Tumours criteria and evaluated for surgery by a specialized group of thoracic surgeons. All histological samples were examined by the same two pathologists. PHR was evaluated by the percentage of viable cells in the tumor and the resected lymph nodes. RESULTS: Forty patients underwent NT ChRT and 27 NT Ch. Fifty-six (83.6%) patients underwent surgery (35 ChRT and 21 Ch). The median time from ChRT to surgery was 6 wk (3-19) and 8 wk (3-21) for Ch patients. We observed significant differences in RR, with disease progression in 2.5% and 14.8% of patients with ChRT and Ch, respectively, and partial response in 62.5% ChRT vs 29.6% Ch (P = 0.025). In PHR we observed ≤ 10% viable cells in the tumor in 19 (54.4%) and 2 cases (9.5%), and in the resected lymph nodes (RLN) 30 (85.7%) and 7 (33.3%) in ChRT and Ch, respectively (P = 0.001). Downstaging was greater in the ChRT compared to the Ch group (80% vs 33.3%; P = 0.002). In the univariate analysis, NT ChRT had a significant impact on partial RR [odds ratio (OR) 12.5; 95% confidence interval (CI): 1.21 - 128.61; P = 0.034], a decreased risk of persistence of cancer cells in the tumor and RLN and an 87.5% increased probability for achieving downstaging (OR 8; 95%CI: 2.34-27.32; P = 0.001). CONCLUSION: We found significant benefits in RR and PHR by adding RT to Ch as NT. A longer follow-up is necessary to assess the impact on clinical outcomes.