Urinary incontinence (UI) is a common side effect of prostate cancer treatment, but in clinical practice, it is difficult to predict. Machine learning (ML) models have shown promising results in ...predicting outcomes, yet the lack of transparency in complex models known as "black-box" has made clinicians wary of relying on them in sensitive decisions. Therefore, finding a balance between accuracy and explainability is crucial for the implementation of ML models. The aim of this study was to employ three different ML classifiers to predict the probability of experiencing UI in men with localized prostate cancer 1-year and 2-year after treatment and compare their accuracy and explainability.
We used the ProZIB dataset from the Netherlands Comprehensive Cancer Organization (Integraal Kankercentrum Nederland; IKNL) which contained clinical, demographic, and PROM data of 964 patients from 65 Dutch hospitals. Logistic Regression (LR), Random Forest (RF), and Support Vector Machine (SVM) algorithms were applied to predict (in)continence after prostate cancer treatment.
All models have been externally validated according to the TRIPOD Type 3 guidelines and their performance was assessed by accuracy, sensitivity, specificity, and AUC. While all three models demonstrated similar performance, LR showed slightly better accuracy than RF and SVM in predicting the risk of UI one year after prostate cancer treatment, achieving an accuracy of 0.75, a sensitivity of 0.82, and an AUC of 0.79. All models for the 2-year outcome performed poorly in the validation set, with an accuracy of 0.6 for LR, 0.65 for RF, and 0.54 for SVM.
The outcomes of our study demonstrate the promise of using non-black box models, such as LR, to assist clinicians in recognizing high-risk patients and making informed treatment choices. The coefficients of the LR model show the importance of each feature in predicting results, and the generated nomogram provides an accessible illustration of how each feature impacts the predicted outcome. Additionally, the model's simplicity and interpretability make it a more appropriate option in scenarios where comprehending the model's predictions is essential.
Objectives: The aim is to evaluate the incidental dose to the lymphatic regions in prostate-only radiotherapy (PORT) and to compare hematological outcome between PORT and whole pelvic radiotherapy ...(WPRT) in node-positive prostate cancer (pN1 PCa), in the era of modern radiotherapy techniques. Methods: We performed a prospective phase 3 trial in which a total of 64 pN1 PCa patients were randomized between PORT (ARM A) and WPRT (ARM B) delivered with volumetric-modulated arc therapy (VMAT). The lymph node (LN) regions were delineated separately and differences between groups were calculated using Welch t-tests. Hematological toxicity was scored according to common terminology criteria for adverse events (CTCAE) version 4.03. To evaluate differences in the evolution of red blood cell (RBC), white blood cell (WBC), and platelet count over time between PORT and WPRT, 3 linear mixed models with a random intercept for the patient was fit with model terms randomization group, study time point, and the interaction between both categorical predictors. Results: Except for dose to the obturator region, the incidental dose to the surrounding LN areas was low in ARM A. None of the patients developed severe hematological toxicity. The change in RBC from time point pre-external beam radiotherapy (EBRT) to month 3 and for WBC from time point pre-EBRT to months 3 and 12 was significantly different with ARM B showing a larger decrease. Conclusion: The incidental dose to the lymphatic areas becomes neglectable when PORT is delivered with VMAT. Hematological toxicity is very low after WPRT with VMAT and when bone marrow constraints are used for planning, although WPRT causes a decrease in RBC and WBC count over time.
•A decline of at least 17% in prostate cancer diagnoses was seen during the first COVID-19 wave.•Diagnoses restored largely but remained at least 5% lower compared to 2018–2019.•The decrease was most ...prominent amongst elderly and in low-risk localised cancer.•Observed changes in treatment regimens were limited and temporary.•Surgical capacity concerning radical prostatectomy was not compromised.
The COVID-19 outbreak has affected care for non-COVID diseases like cancer. We evaluated the impact of the COVID-19 outbreak on prostate cancer care in the Netherlands.
Prostate cancer diagnoses per month in 2020–2021 versus 2018–2019 were compared based on preliminary data of the Netherlands Cancer Registry (NCR) and nationwide pathology network. Detailed data was retrieved from the NCR for the cohorts diagnosed from March-May 2020 (first COVID-19 wave) and March-May 2018–2019 (reference). Changes in number of diagnoses, age, disease stage and first-line treatment were compared.
An initial decline of 17% in prostate cancer diagnoses during the first COVID-19 wave was observed. From May onwards the number of diagnoses started to restore to approximately 95% of the expected number by the end of 2020. Stage at diagnosis remainedstable over time. In low-risk localised prostate cancer radical prostatectomy was conducted more often in week 9–12 (21% versus 12% in the reference period; OR=1.9, 95% CI; 1.2–3.1) and less active surveillance was applied (67% versus 78%; OR=0.6, 95% CI; 0.4–0.9). In the intermediate-risk group, a similar change was observed in week 13–16. Radical prostatectomy volumes in 2020 were comparable to 2018–2019.
During the first COVID-19 wave the number of prostate cancer diagnoses declined. In the second half of 2020 this largely restored although the number remained lower than expected. Changes in treatment were temporary and compliant with adapted guidelines. Although delayed diagnoses could result in a less favourable stage distribution, possibly affecting survival, this seems not very likely.
Patients who underwent restaging prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA-PET/CT) for biochemically recurrent disease after radical prostatectomy had ...better short-term oncological outcomes after salvage radiation therapy (SRT) than those who underwent “blind” SRT. Thus, PSMA-PET/CT is associated with an improved oncological outcome in a selected series of patients.
Radiolabeled prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) has shown superior diagnostic accuracy to conventional imaging for the detection of prostate cancer deposits . Consequently, clinical management changes have been reported in patients with biochemical recurrence (BCR) of disease after robot-assisted radical prostatectomy (RARP). We hypothesized that, due to the exclusion of patients with metastatic disease on PSMA-PET/CT, those who underwent local salvage radiation therapy (SRT) after restaging PSMA-PET/CT for BCR may have better oncological outcomes than patients who underwent “blind” SRT.
To compare the oncological outcome of a patient cohort that underwent PSMA-PET imaging prior to SRT with that of a patient cohort that did not have PSMA-PET imaging before SRT.
We included 610 patients who underwent SRT, of whom 298 underwent PSMA-PET/CT prior to SRT and 312 did not. No additional hormonal therapy was prescribed.
To compare both cohorts, case-control matching was performed, using the prostate-specific antigen (PSA) value at the initiation of SRT, pathological grade group, pathological T stage, surgical margin status, and biochemical persistence after RARP as matching variables. The outcome variable was biochemical progression at 1 yr after SRT, defined as either a rise of PSA ≥0.2 ng/ml above the nadir after SRT or the start of additional treatment.
After case-control matching, 216 patients were matched in both cohorts (108 patients per cohort). In the patient cohort without PSMA-PET/CT prior to SRT, of 108 patients, 23 (21%) had biochemical progression of disease at 1 yr after SRT, compared with nine (8%) who underwent restaging PSMA-PET/CT prior to SRT (p = 0.007).
PSMA-PET/CT is found to be associated with an improved oncological outcome in patients who undergo SRT for BCR after RARP.
Performing prostate-specific membrane antigen positron emission tomography/computed tomography imaging in patients with biochemical recurrence of disease after robot-assisted radical prostatectomy, before initiating salvage radiation therapy, resulted in improved short-term oncological outcomes.
To develop an approach to the diagnosis and treatment of prostate cancer using one platform for fusion biopsy, followed by focal gland ablation utilizing permanent prostate brachytherapy with and ...without a rectal spacer.
Prostate phantoms containing multiparametric magnetic resonance imaging (mpMRI) regions of interest (ROI) underwent fusion biopsy, followed by image co-registration of positive sites to a treatment planning brachytherapy program. A partial hemi-ablation and both posterior lobes using a Mick applicator and linked stranded seeds were simulated. Dummy sources were modeled as iodine-125 (
I) with a prescribed dose of at least 210 Gy to gross tumor (GTV) and clinical target volume (CTV), as defined by mpMRI visible ROI and surrounding negative biopsy sites. Computer tomograms (CT) were performed post-implant prior to and after rectal spacer insertion. Different prostate and rectal constraints were compared with and without the spacer.
The intra-operative focal volumes of CTV ranged from 6.2 to 14.9 cc (mean, 11.3 cc), and the ratio of focal volume/whole prostate volume ranged between 0.19 and 0.42 (mean, 0.31). The intra- and post-operative mean focal D
of GTV, CTV, and for the entire prostate gland was 265 Gy and 235 Gy, 214 Gy and 213 Gy, and 66.1 Gy and 57 Gy, respectively. On average, 13 mm separation was achieved between the prostate and the rectum (range, 12-14 mm) on post-operative CT. The mean doses in Gy to 2 cc of the rectum (D
) without spacer vs. with spacer were 39.8 Gy vs. 32.6 Gy, respectively.
Doses above 200 Gy and the implantation of seeds in clinically significant region for focal therapy in phantoms are feasible. All rectal dosimetric parameters improved for the spacer implants, as compared with the non-spacer implants. Further validation of this concept is warranted in clinical trials.
To evaluate the rate of vaginal, pelvic, and distant failures and acute toxicity after postoperative vaginal vault brachytherapy (VBT) delivered by a ring applicator in women with high ...intermediate-risk endometrial cancer.
A total of 100 patients were treated with VBT after a total abdominal hysterectomy and bilateral salpingo-oophorectomy for a Stage IA or IB (International Federation of Gynecology and Obstetrics 2009) intermediate-risk endometrial cancer; 26 patients received 30-Gy low-dose-rate, 74 patients received 28-Gy pulsed-dose-rate brachytherapy.
At a median followup of 37 months (range, 1-107), 6 (6%) patients showed failures. Three patients developed an in-field recurrence in the vaginal vault: 1 was isolate, whereas the other 2 showed simultaneous pelvic and/or distant failure. A fourth patient developed an out-of-field recurrence in the posterior vaginal wall of the proximal half of the vagina, including pelvic and distant failure. Two other patients showed only distant failure. The estimated 3-year actuarial rate of any vaginal recurrence was 2.6% (95% confidence interval, 0-6.3%). The 5-year overall survival was 84%, similar to that in the female Dutch population matched for age and date of diagnosis. The acute side effects were low, consisting mainly of the occurrence of temporary diarrhea (2%).
Postoperative VBT by a ring applicator results in a low recurrence risk, survival rates comparable with the normal female population, and a very low risk of acute morbidity.
External Beam Radiotherapy (EBRT) techniques dramatically changed over the years. This may have affected the risk of radiation-induced second primary cancers (SPC), due to increased irradiated low ...dose volumes and scatter radiation. We investigated whether patterns of SPC after EBRT have changed over the years in prostate cancer (PCa) survivors.
PCa survivors diagnosed between 1990-2014 were selected from the Netherlands Cancer Registry. Patients treated with EBRT were divided in three time periods, representing 2-dimensional Radiotherapy (RT), 3-dimensional conformal RT (3D-CRT), and the advanced RT (AdvRT) era. Standardized incidence ratios (SIR) and absolute excess risks (AER) were calculated to estimate relative and excess absolute SPC risks. Sub-hazard ratios (sHRs) were calculated to compare SPC rates between the EBRT and prostatectomy cohort. SPCs were categorized by subsite and anatomic region.
PCa survivors who received EBRT had an increased risk of developing a solid SPC (SIR=1.08; 1.05-1.11), especially in patients aged <70 years (SIR=1.13; 1.09-1.16). Pelvic SPC risks were increased (SIR=1.28; 1.23-1.34), with no obvious differences between the three EBRT eras. Non-pelvic SPC were only significantly increased in the AdvRT era (SIR=1.08; 1.02-1.14), in particular for the 1-5 year follow-up period. Comparing the EBRT cohort to the prostatectomy cohort, again an increased pelvic SPC risk was found for all EBRT periods (sHRs= 1.61, 1.47-1.76). Increased non-pelvic SPC risks were present for all RT eras and highest for the AdvRT period (sHRs=1.17, 1.06-1.29).
SPC risk in patients with EBRT is increased and remained throughout the different EBRT eras. The risk of developing a SPC outside the pelvic area changed unfavorably in the AdvRT era. Prolonged follow-up is needed to confirm this observation. Whether this is associated with increased irradiated low-dose volumes and scatter, or other changes in clinical EBRT practice, is the subject of further research.
Abstract Background and purpose: Oesophageal cancer is the sixth leading cause of cancer death worldwide and radiotherapy plays a prominent role in its treatment. The presence of lymph node (LN) ...metastasis has been demonstrated to be one of the most significant prognostic factors related to oesophageal cancer. The use of elective lymph node irradiation (ENI) is still a topic of persistent controversy. The conservative school is to irradiate positive lymph nodes only; the other school is to prophylactically irradiate the regional lymph node area according to different tumour sites. This review investigated the justification for including ENI in the treatment of patients with oesophageal cancer. Material and methods: We performed a systematic literature search to find surgical data about lymph node distribution depending on different tumour subgroups: early, cervical, thoracic and gastroesophageal junction cancer. Furthermore, we performed a qualitative assessment of recurrence patterns in patients treated with or without ENI to derive estimates of the potential area at risk for lymph node harvest. Results: We identified and reviewed 49 studies: 10 in early, 8 in cervical, 10 in thoracic and the remaining 21 in gastroesophageal junction cancer. In general, these studies were conclusive in incidence and location of pathologic lymph nodes for different subgroups. Data for lymph node recurrence patterns are scarce and contributed little to our review. Conclusions: This review resulted in five recommendations for radiation oncologists in daily practice. We used the available evidence about metastatic lymph node distribution to develop a careful reasonable radiation protocol for the corresponding tumour subgroups.
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