Photon-based high-dose single-fraction radiosurgery, an effective treatment modality for recurrent uveal melanoma.

Introduction: To evaluate and report the outcome of a patient with locally recurrent uveal melanoma (UM) previously treated with brachytherapy (BT), using a second personalized globe-sparing radiotherapy approach. Material and methods: In June 2020, a 78-year-old man arrived at our institution with diplopia and suspected uveal melanoma. At the ophthalmological evaluation (B-scan and A-scan ultrasonography) a lesion in the right eye at 6-7 hours of about 5 mm thickness, with internal lacunar areas, approximately 7 mm away from the limbus, was observed. The patient underwent ruthenium plaque BT at a total dose of 110 Gy prescribed to the apex of the tumour. At the follow-up, the lesion was under control until September 2021, but it recurred with a satellite exudative detachment in the lower and temporal sectors 7-10 hours. At the B-scan the lesion had a maximum thickness of 4.6 mm. Subsequently, in a multidisciplinary discussion, one single fraction stereotactic radiosurgery was scheduled. The prescribed dose was 27 Gy in the de-novo lesion and 24 Gy in the previously irradiated site. Stereotactic radiosurgery was performed in October 2021. Results: The time interval between the 2 treatments was 15 months. Twenty months after recurrence, local tumour control was observed, and no metastases were detected on follow-up examinations. No severe acute or late toxicity was observed due to the retreatment. Conclusions: Photon stereotactic radiotherapy is a feasible, acceptably tolerated modality, and it represents an eye-preserving treatment also for patients with recurrent UM unfit for BT.

High-dose-rate brachytherapy for non-melanoma skin cancer using tailored custom moulds - a single-centre experience.

AIM OF THE STUDY: The aim of this retrospective study was to analyse tumour control, toxicity, and aesthetic outcome of patients affected by non-melanoma skin cancer (NMSC) treated with 192 Ir high-dose-rate (HDR)-brachytherapy (BT) at the Division of Radiotherapy, University of Pisa. MATERIAL AND METHODS: From January 2014 to December 2019 we treated 37 patients (median age 79 years; range 31-91 years) affected by NMSC, with the following histological subtypes: 62.2% basal cell carcinoma and 37.8% squamous cell carcinoma. We analysed 40 lesions with a depth ≤ 5 mm, located in 40.0% scalp, 17.5% nose, 25.0% face, and 17.5% ear, all treated with 192 Ir-based HDR-BT, using tailored custom moulds, with a median of 5 catheters (range, 1-9) spaced 1 cm apart. The most common fractionation scheme was 40 Gy in 8 daily fractions; the biological effective dose was 60 Gy. RESULTS: The median follow-up was 25 months (range, 3-70 months). The 2-year local control rate was 90%. Common terminology criteria for adverse event (CTCAE vs. 5.0) G1 toxicities were dermatitis (52%), pain (25%), and ulceration (22%). The only G2 acute toxicities were dermatitis and ulceration. The most common G1 late toxicities were fibrosis (17%), atrophy (15%), and hypopigmentation (12%). No G3 or higher acute or late toxicity was reported. Excellent cosmetic results were observed in 65.0% of the lesions; only 1 case (2.5%) reported a poor cosmetic result. CONCLUSIONS: Surface mould HDR-BT is a safe, effective, and well tolerated treatment modality for NMSC and can be considered a good alternative, especially for elderly patients who are often unfit for surgery.

INVERTED INTERNAL LIMITING MEMBRANE FLAP TECHNIQUE FOR MACULAR HOLE SURGERY WITHOUT EXTRA MANIPULATION OF THE FLAP.

PURPOSE: To determine whether surgical manipulation steps of the internal limiting membrane (ILM) flap, such as ILM trimmed, ILM tuck inside the hole, ILM massage, are mandatory to obtain satisfactory outcomes for the repair of large stage IV idiopathic macular hole using the inverted ILM flap technique. METHODS: In this interventional comparative prospective single-masked study, 81 eyes were randomized into 2 treatments groups. In Group 1 (41 eyes), the classic inverted ILM flap technique was performed. In Group 2 (40 eyes), a modified procedure was used: after ILM peeling, no extra flap manipulation was performed. The macular hole was covered by the inverted ILM flap because of the air pressure at the time of the fluid-air exchange. RESULTS: At 12 months, macular hole closure was observed in 40 eyes (97.6%) in Group 1 and in 39 eyes in Group 2 (97.5%). U-shape closure rate, ellipsoid zone defects, and external limiting membrane defects were similar in both groups. The results indicate no statistical difference in anatomical and functional success between both groups. CONCLUSION: The macular hole closure rate, improved visual acuity, and no extra complications indicate noninferiority of the modified inverted ILM technique. Internal limiting membrane finishing, tucking, and massage may not be required to obtain surgical success.

Iodine Plaque Brachytherapy a Customized Conservative Approach to the Management of Medium/Large-sized Uveal Melanoma.

BACKGROUND/AIM: The objective of this study was to assess the role of iodine (125I) plaque brachytherapy in the management of uveal melanoma. PATIENTS AND METHODS: This is a retrospective study of 50 patients (median age 67 years; range=33-86 years) with uveal melanoma, treated with 125I plaque brachytherapy at the University Hospital of Pisa. Uveal melanoma was diagnosed with A-scan and B-scan standardized echography, fluorescein angiography, indocyanine green-angiography, optical coherence tomography, and/or magnetic resonance imaging. The primary outcomes assessed were local control, overall survival, disease progression, globe preservation, and metastases. Secondary outcomes were acute and late radiation adverse effects. RESULTS: Inclusion criteria comprised Eastern Cooperative Oncology Group performance status ≤2, life expectancy >6 months, and tumor thickness ≤10 mm and\or diameter ≤20 mm. All the patients were treated with 125I plaque brachytherapy, with a prescription dose of 85 Gy to the tumor apex. The 5-year rate of local control, progression-free survival, metastasis-free survival, enucleation-free survival, and overall survival were 83.0%, 81.4%, 90.3%, 83.1%, and 92.1% respectively. Twenty-four patients (48.0%) had one or more acute and late toxicities. The most common acute adverse events (CTCAE vs. 5.0) grade 1-3 were conjunctivitis and eye pain (6.0%). Regarding late events, radiation retinopathy grade 1-3 occurred in 18.0% of cases, while grade 1-3 vitreous hemorrhage in 2.5%. CONCLUSION: 125I plaque brachytherapy offers an effective and safe approach for selected cases of uveal melanoma, due to the reported satisfactory results in terms of local control, eye conservation and survival.

Electron FLASH radiotherapy in vivo studies. A systematic review.

FLASH-radiotherapy delivers a radiation beam a thousand times faster compared to conventional radiotherapy, reducing radiation damage in healthy tissues with an equivalent tumor response. Although not completely understood, this radiobiological phenomenon has been proved in several animal models with a spectrum of all kinds of particles currently used in contemporary radiotherapy, especially electrons. However, all the research teams have performed FLASH preclinical studies using industrial linear accelerator or LINAC commonly employed in conventional radiotherapy and modified for the delivery of ultra-high-dose-rate (UHDRs). Unfortunately, the delivering and measuring of UHDR beams have been proved not to be completely reliable with such devices. Concerns arise regarding the accuracy of beam monitoring and dosimetry systems. Additionally, this LINAC totally lacks an integrated and dedicated Treatment Planning System (TPS) able to evaluate the internal dose distribution in the case of in vivo experiments. Finally, these devices cannot modify dose-time parameters of the beam relevant to the flash effect, such as average dose rate; dose per pulse; and instantaneous dose rate. This aspect also precludes the exploration of the quantitative relationship with biological phenomena. The dependence on these parameters need to be further investigated. A promising advancement is represented by a new generation of electron LINAC that has successfully overcome some of these technological challenges. In this review, we aim to provide a comprehensive summary of the existing literature on in vivo experiments using electron FLASH radiotherapy and explore the promising clinical perspectives associated with this technology.

Lymph-vascular Space Involvement and/or p53 Overexpression Correlated With the Clinical Outcome of Early-stage Endometrial Cancer Patients Treated With Adjuvant Vaginal Brachytherapy.

BACKGROUND/AIM: The majority of patients with endometrial cancer (EC) are diagnosed at an early stage and undergo primary surgery, followed by observation or adjuvant therapy according to risk factors on surgical samples. The objective of this study was to assess the correlation between a risk profile represented by the presence of substantial lymph-vascular space involvement (LVSI) and/or p53 overexpression and the clinical outcome of patients with early-stage endometrial cancer (EC) who received adjuvant vaginal brachytherapy (BT). PATIENTS AND METHODS: This investigation assessed 79 patients who underwent hysterectomy, bilateral salpingo-oophorectomy, and pelvic and/o aortic lymphadenectomy or sentinel lymph node biopsy followed by hypofractionated (HDR)-vaginal BT, using 192Ir source, for stage I-II endometrioid (n=70) or non-endometrioid (n=9) EC. Thirty-four patients (43.0%) were considered to have an unfavorable risk profile defined by the presence of substantial LVSI and /or p53 overexpression. RESULTS: Five-year disease-free survival (DFS) and five-year overall survival (OS) were 93.7% and 95%, respectively. There was a significant correlation between unfavorable risk-profile and pelvic recurrence rate (p=0.002) and distant recurrence rate (p=0.017). Patients with abnormal p53 had a higher risk of local relapse (p=0.041). Substantial LVSI was strongly associated with pelvic recurrence (p=0.001) and distant metastasis (p<0.001). CONCLUSION: The presence of substantial LVSI and/or p53 overexpression strictly correlated with poor outcome of patients with early-stage EC and should be taken into consideration for better planning adjuvant treatment in this clinical setting.

Cancer Stem Cells and Glioblastoma: Time for Innovative Biomarkers of Radio-Resistance?

Despite countless papers in the field of radioresistance, researchers are still far from clearly understanding the mechanisms triggered in glioblastoma. Cancer stem cells (CSC) are important to the growth and spread of cancer, according to many studies. In addition, more recently, it has been suggested that CSCs have an impact on glioblastoma patients' prognosis, tumor aggressiveness, and treatment outcomes. In reviewing this new area of biology, we will provide a summary of the most recent research on CSCs and their role in the response to radio-chemotherapy in GB. In this review, we will examine the radiosensitivity of stem cells. Moreover, we summarize the current knowledge of the biomarkers of stemness and evaluate their potential function in the study of radiosensitivity.

Photon-based High-dose Single-fraction Radiosurgery, an Effective Treatment Modality for Large and Posterior Uveal Melanoma.

BACKGROUND/AIM: Uveal melanoma (UM) is the most common primary intraocular malignant tumor. This malignancy is frequently treated using brachytherapy, stereotactic radiotherapy, or proton therapy. The objective of this study was to assess the role of stereotactic radiosurgery in the treatment of large and posterior UM. PATIENTS AND METHODS: From January 2014 to July 2021, we treated 65 patients (median age=71 years; range=31-89 years) affected by UM. Inclusion criteria were Eastern Cooperative Oncology Group (ECOG) performance status (PS) ≤2, life expectancy >6 months, tumor thickness >10 mm, diameter >16 mm or posterior UM. The treatment was delivered with a True Beam™ LINAC with arc modulation technique. All patients received 27 Gy in one fraction (biological effective dose ≈100 Gy, assuming an α/ß of 10). RESULTS: The median follow-up was 36 (range=3-90) months. Acute toxicities were reported in 14 patients, whereas late toxicity occurred in 45 (69.2%). Fifteen patients (23.0%) underwent enucleation: eight (12.3%) for failure of local control and seven (10.7%) for late treatment co-morbidities. The 5-year local control, and progression-free, metastasis-free, enucleation-free, and overall survival rates were 80%, 43%, 62%, 65% and 56%, respectively. In multivariate analysis, tumor dimensions significantly influenced survival [larger basal diameter: progression-free [hazard ratio (HR)=2.42] and overall (HR=2.61) survival; greater thickness: overall survival (HR=2.36)]. In multivariate analysis, patients without local control had a higher risk of distant metastasis (HR=3.25). CONCLUSION: Stereotactic radiosurgery offers an effective and safe approach for selected cases of UM due to the satisfactory results in terms of local control, eye conservation and survival.

Early Versus Late Postoperative Radiotherapy in Patients With Prostate Cancer: Results of a Single-centre Retrospective Study.

BACKGROUND/AIM: A much-debated topic relating to patients at risk of local prostate cancer recurrence, but with post-operative leveIs of prostate-specific antigen (PSA) lower than 0.2 ng/ml, concerns the best timing of postoperative radiotherapy (RT), adjuvant or salvage? The present monocentric, retrospective study aimed to investigate the best PSA value at which to plan salvage RT for patients with recurrent prostate cancer. PATIENTS AND METHODS: From January 2011 to December 2019, 158 patients were treated with adjuvant RT at Pisa University Hospital, whilst 91 patients underwent salvage RT. We grouped the patients treated with salvage RT using their PSA values at the time of salvage RT: PSA >0.5 ng/ml, PSA between 0 and 0.5 ng/ml, and PSA ≤0.2 ng/ml. The median follow-up was 63 months. Biochemical recurrence-free survival (BFS) measured from surgery was the primary endpoint. RESULTS: Salvage RT led to shorter BFS compared to adjuvant RT considering the whole cohort of patients, with a hazard ratio of 3.195 (95% confidence interval=1.534-6.655, p=0.002). However, analysing only the group of patients with PSA ≤0.2 ng/ml at the time of salvage RT, salvage RT led to BFS similar to that achieved with adjuvant RT (p=0.35). CONCLUSION: Our results suggest that when scheduled for patients with a PSA ≤0.2 ng/ml, salvage RT results in equivalent biochemical control to that with adjuvant RT.

Two different sizes of Valencia applicators in non-melanoma skin cancer treatment with iridium-192 high-dose-rate brachytherapy.

PURPOSE: The aim of this retrospective study was to analyze tumor control, toxicity, and aesthetic outcome of patients affected by non-melanoma skin cancer (NMSC) and treated with iridium-192 (192Ir) high-dose-rate (HDR) brachytherapy (BT) using Valencia applicators at the Division of Radiotherapy, University of Pisa. MATERIAL AND METHODS: From June 2015 to December 2020, 95 NMSC patients, including 61.5% basal cell carcinoma and 38.5% squamous cell carcinoma patients, with median age of 83 years (range, 32-96 years) were treated. In total, 182 lesions with a diameter ≤ 25 mm (median, 12 mm) and a depth ≤ 4 mm, located in scalp (19.2%), face (20.9%), chest (8.8%), nose (16.5%), ear (15.4%), and extremities (19.2%) were analyzed. All lesions were treated with 192Ir-based HDR afterloader using Valencia applicators. 105 lesions (57.7%) were treated with applicator of 20 mm and 77 lesions (42.3%) with applicator of 30 mm in diameter, depending on the size of lesions. Prescribed dose was 40 Gy in 8 fractions (5 Gy/fraction) delivered 2-3 times a week. Biological effective dose (BED) was ≈ 60 Gy. RESULTS: The median follow-up was 14 months (range, 3-59 months). The 2-year local control rate was 96%. According to common terminology criteria for adverse events (CTCAE v. 5.0), G1-G2 acute toxicities included dermatitis (22.0%) and pain (8.2%). The most common G1 late toxicities were hypopigmentation (27.5%) and fibrosis (8.2%), and G2 late toxicity included ulceration (0.5%). No G3 or higher acute or late toxicities were reported. Excellent cosmetic results were observed in 77.5% of the lesions, with one only (0.5%) reported as a poor cosmetic result (ulceration refractory to therapy). CONCLUSIONS: HDR-BT using Valencia applicators is a safe, effective, and well-tolerated treatment modality for NMSC, and can be considered a good alternative for treatment, especially in elderly patients who are often unfit for surgery.

Adjuvant Radiotherapy in Patients With Pancreatic Adenocarcinoma. Is It Still Appealing in Clinical Trials? A Meta-analysis and Review of the Literature.

AIM: Pancreatic adenocarcinoma is a life-threatening disease with a rising frequency and the fourth leading cause of cancer death. This review aimed to assess the impact of postoperative radiotherapy through a meta-analysis of prospective randomized studies. MATERIALS AND METHODS: Six studies met the inclusion criteria and were analyzed to calculate the cumulative risk of death (hazard ratio) in patients affected by pancreatic cancer treated with or without radiotherapy. Higgins' index was used to determine heterogeneity in between-study variability and, subsequently, the random-effects model was applied according to DerSimonian and Laird. RESULTS: Eight hundred and thirty-seven patients were analyzed (418 in the control arm and 419 in the treatment one), the hazard ratio for death after randomization was 0.92 (p=0.560, 95% confidence interval=0.70-1.22). When scrutinizing these studies, only one out of six showed a statistically significant benefit due to the addition of radiotherapy in the postoperative setting. CONCLUSION: We conclude that the use of adjuvant radiotherapy is not beneficial in treating all patients affected by pancreatic cancer but only for a subset of cases with potential residual local disease.

Radiotherapy in the COVID-19 Pandemic Era.

BACKGROUND/AIM: In 2020, because of coronavirus pandemic, medical activities changed. The aim of this report is to compare the volumes of Pisa radiotherapy activities from March 9th to May 31st, 2020, with the same period in 2019. PATIENTS AND METHODS: We analyzed the activity of our Unit to evaluate how logistics changes, related to the COVID-19 epidemic, impacted on volumes of radiotherapy (RT) activity and on the number of cases of COVID-19 infections observed in healthcare professionals and patients. RESULTS: The total number of first-time visits between March-May 2020 was reduced by 18%, probably due to delays in diagnosis and histological tests as well as the temporary closure of the operating rooms. None of the healthcare professionals and only two patients contracted the infection. CONCLUSION: We were able to treat all patients referred to our hospital and we were able to reduce risk of infection for both our patients and healthcare staff, guaranteeing continuum of care for our oncological patients.