Stereotactic Body Radiotherapy for Kidney Cancer: Ready for Prime Time?

The standard treatment for renal cell carcinoma (RCC) is surgery. However, a number of patients will not be candidates for surgical treatment or will reject this therapeutic approach. Therefore, alternative approaches are required. Historically, radiotherapy has been considered an ineffective treatment for RCC due to the radioresistance of renal tumour cells to conventional fractionation and the increased rate of toxicity. Stereotactic body radiotherapy (SBRT) is a radiotherapy technique that provides a non-invasive ablative treatment with remarkable rates of local control in both primary tumours and metastases in several locations, with a low associated morbidity due to the highly conformal dose and the use of image-guided techniques. Current evidence shows that a higher dose per fraction, achieving a higher biological effective dose, can overcome the radioresistance of RCC cells. Therefore, SBRT, as well as the combination of SBRT and new emerging immune therapies, has a potential role in the local treatment of primary RCC and oligometastatic RCC patients.

A multicenter LArge retrospectIve daTabase on the personalization of stereotactic ABlative radiotherapy use in lung metastases from colon-rectal cancer: The LaIT-SABR study.

INTRODUCTION: Stereotactic ablative radiotherapy (SABR) has been shown to increase survival in oligometastatic disease, but local control of colorectal metastases remains poor. We aimed to identify potential predictive factors of SBRT response through a multicenter large retrospective database and to investigate the progression to the polymetastatic disease (PMD). MATERIAL AND METHODS: The study involved 23 centers, and was approved by the Ethical Committee (Prot. Negrar 2019-ZT). 1033 lung metastases were reported. Clinical and biological parameters were evaluated as predictive for freedom from local progression-free survival (FLP). Secondary end-point was the time to the polymetastatic conversion (tPMC). RESULTS: Two-year FLP was 75.4%. Two-year FLP for lesions treated with a BED < 00 Gy, 100-124 Gy, and ≥125 Gy was 76.1%, 70.6%, and 94% (p = 0.000). Two-year FLP for lesion measuring ≤10 mm, 10-20 mm, and >20 mm was 79.7%, 77.1%, and 66.6% (p = 0.027). At the multivariate analysis a BED ≥125 Gy significantly reduced the risk of local progression (HR 0.24, 95%CI 0.11-0.51; p = 0.000). Median tPMC was 26.8 months. Lesions treated with BED ≥125 Gy reported a significantly longer tPMC as compared to lower BED. The median tPMC for patients treated to 1, 2-3 or 4-5 simultaneous oligometastases was 28.5, 25.4, and 9.8 months (p = 0.035). CONCLUSION: The present is the largest series of lung colorectal metastases treated with SABR. The results support the use of SBRT in lung oligometastatic colorectal cancer patients as it might delay the transition to PMD or offer relatively long disease-free period in selected cases. Predictive factors were identified for treatment personalization.

Postoperative radiotherapy after upfront radical prostatectomy: debated issues at a turning point-a survey exploring management trends on behalf of AIRO (Italian Association of Radiotherapy and Clinical Oncology).

OBJECTIVES: Postoperative prostate cancer patients are a heterogeneous population, and many prognostic factors (e.g., local staging, PSA kinetics, margin status, histopathological features) may influence their clinical management. In this complex scenario, univocal recommendations are often lacking. For these reasons, the present survey was developed by the Italian Association of Radiotherapy and Clinical Oncology (AIRO) to collect the opinion of Italian radiation oncologists and delineate a representation of current clinical practice in our country. METHODS: A questionnaire was administered online to AIRO (Italian Association of Radiotherapy and Clinical Oncology) members registered in 2020 with a clinical interest in uro-oncological disease. RESULTS: Sixty-one per cent of AIRO members answered the proposed survey. Explored topics included career and expertise, indications to adjuvant RT, additional imaging in biochemical recurrence setting, use of salvage radiotherapy (SRT), management of clinically evident locoregional recurrence and future considerations. CONCLUSIONS: Overall, good level of agreement was found between participants for most of the topics. Most debated issues regarded, as expected, implementation of new imaging methods in this setting. Notably, trend in favour of early SRT vs. immediate adjuvant RT was underlined, and preference for global evaluation rather than isolated risk factors for RT indications was noticed.

Radical cystectomy versus organ-sparing trimodality treatment in muscle-invasive bladder cancer: A systematic review of clinical trials.

BACKGROUND: Radical cystectomy (RC) represents the mainstay of treatment in patients with muscle-invasive urinary bladder cancer but how it compares with the best organ preservation approach is not known. MATERIALS AND METHODS: The objective of our review is to compare the 5-year overall survival (OS) rates from retrospective and prospective studies of RC and trimodality treatment (TMT), i.e. concurrent delivery of chemotherapy and radiotherapy after a transurethral resection of bladder tumor (TURBT), involving a total of 10,265 and 3131 patients, respectively. We used random-effect models to pool outcomes across studies and compared event rates of combined outcomes for TMT and RC using an interaction test. RESULTS: The median 5-year OS rate was 57% in the TMT group, when compared with 52% (P=0.04), 51% (P=0.02) and 53% (P=0.38) in the whole group receiving RC or the group treated with RC alone or RC+chemotherapy, respectively. The hazard risk (HR) of mortality of patients treated with TMT or RC was 1.22 (95% CI=1.13-1.32) with an absolute benefit of 5% in favor of the former. The HR of mortality from TMT persisted significantly better not only versus the group treated with RC alone (HR=1.22; 95% CI=1.12-1.32), but also versus the group receiving RC+chemotherapy (HR=1.22; 95% CI=1.09-1.36). Multivariate analysis confirmed TMT as a significant prognostic variable for both RC alone and RC+chemotherapy. CONCLUSION: Compared with RC, TMT seems to be associated with a better outcome for patients with muscle-invasive bladder cancer (MIBC). The addition of chemotherapy may improve the RC outcome in some subgroups of patients with a higher probability of micrometastases. Prospective randomized trials are urged to verify these findings and better define the role of organ preservation and radical treatment strategy in the management of patients with MIBC.

Patterns of CT lung injury and toxicity after stereotactic radiotherapy delivered with helical tomotherapy in early stage medically inoperable NSCLC.

OBJECTIVE: To evaluate toxicity and patterns of radiologic lung injury on CT images after hypofractionated image-guided stereotactic body radiotherapy (SBRT) delivered with helical tomotherapy (HT) in medically early stage inoperable non-small-cell lung cancer (NSCLC). METHODS: 28 elderly patients (31 lesions) with compromised pulmonary reserve were deemed inoperable and enrolled to undergo SBRT. Patterns of lung injury based on CT appearance were assessed at baseline and during follow up. Acute (6 months or less) and late (more than 6 months) events were classified as radiation pneumonitis and radiation fibrosis (RF), respectively. RESULTS: After a median follow-up of 12 months (range, 4-20 months), 31 and 25 lesions were examined for acute and late injuries, respectively. Among the former group, 25 (80.6%) patients showed no radiological changes. The CT appearance of RF revealed modified conventional, mass-like and scar-like patterns in three, four and three lesions, respectively. No evidence of late lung injury was demonstrated in 15 lesions. Five patients developed clinical pneumonitis (four patients, grade 2 and one patient, grade 3, respectively), and none of whom had CT findings at 3 months post-treatment. No instance of symptomatic RF was detected. The tumour response rate was 84% (complete response + partial response). Local control was 83% at 1 year. CONCLUSION: Our findings show that HT-SBRT can be considered an effective treatment with a mild toxicity profile in medically inoperable patients with early stage NSCLC. No specific pattern of lung injury was demonstrated. ADVANCES IN KNOWLEDGE: Our study is among the few showing that HT-SBRT represents a safe and effective option in patients with early stage medically inoperable NSCLC, and that it is not associated with a specific pattern of lung injury.

Role of the mitochondrial sodium/calcium exchanger in neuronal physiology and in the pathogenesis of neurological diseases.

In neurons, as in other excitable cells, mitochondria extrude Ca(2+) ions from their matrix in exchange with cytosolic Na(+) ions. This exchange is mediated by a specific transporter located in the inner mitochondrial membrane, the mitochondrial Na(+)/Ca(2+) exchanger (NCX(mito)). The stoichiometry of NCX(mito)-operated Na(+)/Ca(2+) exchange has been the subject of a long controversy, but evidence of an electrogenic 3 Na(+)/1 Ca(2+) exchange is increasing. Although the molecular identity of NCX(mito) is still undetermined, data obtained in our laboratory suggest that besides the long-sought and as yet unfound mitochondrial-specific NCX, the three isoforms of plasmamembrane NCX can contribute to NCX(mito) in neurons and astrocytes. NCX(mito) has a role in controlling neuronal Ca(2+) homeostasis and neuronal bioenergetics. Indeed, by cycling the Ca(2+) ions captured by mitochondria back to the cytosol, NCX(mito) determines a shoulder in neuronal [Ca(2+)](c) responses to neurotransmitters and depolarizing stimuli which may then outlast stimulus duration. This persistent NCX(mito)-dependent Ca(2+) release has a role in post-tetanic potentiation, a form of short-term synaptic plasticity. By controlling [Ca(2+)](m) NCX(mito) regulates the activity of the Ca(2+)-sensitive enzymes pyruvate-, alpha-ketoglutarate- and isocitrate-dehydrogenases and affects the activity of the respiratory chain. Convincing experimental evidence suggests that supraphysiological activation of NCX(mito) contributes to neuronal cell death in the ischemic brain and, in epileptic neurons coping with seizure-induced ion overload, reduces the ability to reestablish normal ionic homeostasis. These data suggest that NCX(mito) could represent an important target for the development of new neurological drugs.

Single fraction partial breast irradiation in prone position.

The purpose of this work is to introduce a new treatment approach and technique for partial breast irradiation in only one session to patients in prone position by using a dedicated positioning device. The patients were treated on a home-made treatment table top that allows the breast to hang down. A particular immobilization system was introduced in order to assure the reproducibility of patient positioning between the CT acquisition session and the treatment session. The clinical target volume (CTV) was outlined according to surgical clips position and/or tumor location on preoperative mammography. Because of negligible movement due to respiration, only an additional margin of 3 mm was added to obtain the planning target volume (PTV). Based on radiobiological calculations, a dose of 21 Gy was prescribed to PTV. The tumor bed was treated with 3D-CRT technique by using 5 fields and rotating the table while the gantry was approximately 90 or 270 degrees. Thirty patients were enrolled for this study chosen in conformity to an approved clinical protocol. The average percentage of PTV volume enclosed in the 90% and 95% of prescribed dose were 99.9 and 98.6% respectively, while only 3.4% of PTV volume received more than 105% of prescribed dose. Dose to 3% of skin volume was, on average, 15.2 Gy. In 97% of patients, less than 50% of the ipsilateral breast received a dose greater than half the prescribed dose. Mean doses to lungs, heart and contralateral breast were negligible. With a median follow-up of 9 months, no important early toxicity was observed both for skin and breast tissue. The treatment of breast tumor bed in prone position in only one session by using the 3D-CRT is technically feasible and seems to be a promising alternative to other accelerated partial breast irradiation techniques.

Rabies prevention in primary care. A four-step approach.

Although most physicians in the United States have not seen a person with rabies, the primary care physician is often confronted with a patient who has been bitten by an animal capable of transmitting rabies virus. Rabies is almost always transmitted by a bite; licks and other nonbite exposures hardly ever cause the disease. The control of rabies in domestic animals has greatly reduced the risk of human disease following the bite of a dog or cat, but rabies in wild animals (especially skunks and raccoons) remains a constant threat. By obtaining epidemiologic information about animal rabies in the area where the exposure occurred, the physician can determine whether the animal in question may have been rabid. If any question remains, owned dogs and cats should be observed for ten days and any other animal should be killed and its brain examined for rabies virus. When postexposure prophylaxis is indicated, it should be administered exactly as recommended herein.