Salvage Low Dose Rate Brachytherapy For Recurrent Prostate Cancer After External Beam Radiotherapy: Results From A Single Institution With Focus On Toxicity And Functional Outcomes.

BACKGROUND/AIM: Low dose rate brachytherapy has been used as salvage therapy for locally recurrent prostate cancer (PC) after primary external beam radiation therapy (EBRT), along with surgery and cryotherapy. All these techniques, in particular, when applied to the whole gland, involve a relatively high risk of toxicity and may worsen the patient's quality of life. Our aim is to evaluate the results of whole-gland salvage brachytherapy (SBT) after primary EBRT in terms of toxicity, functional outcomes, and efficacy. MATERIALS AND METHODS: We retrospectively reviewed clinical data on 19 patients consecutively treated with SBT at our institution between June 2012 and November 2015. Local recurrences were identified with 11C-choline positron emission tomography/computed tomography and pelvic magnetic resonance imaging after biochemical recurrence according to Phoenix criteria (prostate-specific antigen nadir + 2). Low dose rate brachytherapy was performed by 125I permanent seeds implantation to the whole prostate gland, with a prescription dose of 130 Gy. At the time of SBT, only 2 patients were receiving androgen deprivation therapy. Acute and late toxicities were recorded using the CTCAE 4.0 scoring system. Quality of life was assessed using IPSS (International Prostate Symptoms Score) and IIEF (International Index of Erectile Function) questionnaires at baseline and 6, 12, and 24 months after SBT, and the respective mean values were compared using Student t test. Biochemical relapse-free survival (BRFS) was also calculated. RESULTS: Median follow-up after SBT was 24 months. Of 19 patients, 2 patients experienced a G3 cystitis (10.2%) and 1 patient experienced a G4 proctitis (5.3%), respectively. Mean pre-SBT IPSS scores and 6, 12, and 24 months after SBT were 5.84, 10.22, 15.72, and 8.10, respectively. Mean pre-SBT IIEF scores and 6, 12, and 24 months after SBT were 8.42, 3.55, 7.89, and 6.40, respectively. At the time of analysis, only 2 patients showed a biochemical relapse (3-year BRFS 85.2%). The Student t test demonstrated a worsening of functional outcome 6 months and 1 year after treatment but a subsequent improvement 2 years after SBT. CONCLUSIONS: Salvage brachytherapy for recurrent PC after primary EBRT seems to be a feasible treatment for selected patients. Our series revealed a severe toxicity peak 6 months and 1 year after local re-treatment and then they decrease. Early BRFS rates are good. However, these are very preliminary results so further patient accrual, long-term follow-up, and prospective trials are needed in the future.

Could machine learning improve the prediction of pelvic nodal status of prostate cancer patients? Preliminary results of a pilot study.

We tested and compared performances of Roach formula, Partin tables and of three Machine Learning (ML) based algorithms based on decision trees in identifying N+ prostate cancer (PC). 1,555 cN0 and 50 cN+ PC were analyzed. Results were also verified on an independent population of 204 operated cN0 patients, with a known pN status (187 pN0, 17 pN1 patients). ML performed better, also when tested on the surgical population, with accuracy, specificity, and sensitivity ranging between 48-86%, 35-91%, and 17-79%, respectively. ML potentially allows better prediction of the nodal status of PC, potentially allowing a better tailoring of pelvic irradiation.

The impact of tumour histology and recursive partitioning analysis classification on the prognosis of patients treated with whole-brain hypofractionated radiotherapy for brain metastases: analysis of 382 patients.

PURPOSE: Recursive partitioning analysis (RPA) is a prognostic index capable of predicting survival in patients with brain metastases. Histology of the primary tumour has only recently been introduced among the factors that could potentially affect the prognosis of these patients. The main purpose of this study was to analyse the impact of RPA in correlation with histology of the primary tumour in patients with brain metastases treated with hypofractionated radiotherapy. MATERIALS AND METHODS: A total of 382 patients were treated at the Department of Radiotherapy of Brescia University, and RPA classes were retrospectively assigned to all patients. Univariate and multivariate analyses were then performed to verify the role of the single prognostic variables, for the entire group and for each prognostic class, as well as in correlation with histology of the primary tumour. RESULTS: Most patients were classified as RPA prognostic class 2 (48%). The majority of patients was treated with a total dose of 30 Gy delivered in ten fractions, whereas the dose of 20 Gy in four or five fractions was primarily used in patients classified as RPA class 3. At univariate analysis, the main variable correlating with overall survival (OS) was RPA class (p=0.000). Uni- and multivariate analysis performed on RPA class 1 patients only confirmed the role of general performance status, number of metastases and total radiotherapy dose for predicting OS. In the group with the worst prognosis (RPA class 3), none of the variables had a statistically significant role in improving OS. Tumour histology and radiotherapy dose influence OS, even in RPA class 1 and 2 patients. CONCLUSIONS: This analysis confirms that RPA prognostic class is the factor that most predicts survival. Primary tumour histology helps determine prognosis, especially in RPA prognostic classes 1 and 2. As regards RPA class 3, no factor influences survival prognosis.

A benchmark study on 883 nasopharyngeal cancer patients treated in two Italian centres from 1977 to 2000. Part I: Evolving technical choices and survival.

PURPOSE: The authors sought to define treatment results according to the different accrual periods and clinical-therapeutic features in a large series of nasopharyngeal cancer (NPC) patients treated in two Italian centres over more than two decades. MATERIALS AND METHODS: A total of 883 patients consecutively treated with radiotherapy between 1977 and 2000 at the Florence (FLO) and Brescia (IRA) Radiation Oncology centres were studied. Five-year overall (OS) and disease-specific (DSS) actuarial survival rates in the different pathological, clinical and therapeutic subgroups were calculated, along with the actuarial local-regional control (LRC) probability. RESULTS: At univariate analysis, survival and local control rates were significantly better in the more recent accrual periods and in the more favourable disease presentations; treatment-related parameters mainly affect LRC. At multivariate analysis, patient- and disease-related factors had a more evident prognostic effect than did therapeutic factors, although dose to the nasopharynx and treatment technique had a marginally significant impact on DSS and OS. CONCLUSIONS: Results of this benchmark study may be useful for understanding the development of new radio-therapy techniques for NPC, such as three-dimensional conformal radiotherapy (3D-CRT) and particularly intensity-modulated radiotherapy (IMRT).

A benchmark study on 883 nasopharyngeal cancer patients treated in two Italian centres from 1977 to 2000. Part II: Evolving technical choices and toxicity patterns.

PURPOSE: The authors sought to define toxicity patterns according to the different accrual periods and clinical-therapeutic features in a large series of nasopharyngeal cancer (NPC) patients treated in two Italian centres over more than two decades. MATERIALS AND METHODS: A total of 883 patients consecutively treated with radiotherapy from 1977 to 2000 at the Florence (FLO) and Brescia (IRA) radiation oncology centres were studied. The crude incidence of late treatment toxicity in the different subgroups of patients was calculated and compared. RESULTS: Higher total and fractional doses and the "older" treatment techniques were related with an increased incidence of the main late effects of treatment. More recently treated patients experienced less treatment-related complications. CONCLUSIONS: Results of this benchmark study may have implications for understanding and developing new radiotherapy techniques, such as three-dimensional conformal radiotherapy (3D-CRT) and, in particular, intensity-modulated radiotherapy (IMRT) for NPC patients.