Health-related quality of life in localized renal masses: A matter of sparing nephrons or minimizing the incision?

PURPOSE: Longitudinal assessment of health-related quality of life (HRQoL) differences in patients with localized renal masses according to treatment strategy. METHODS: Consecutive patients ≥ 18 years with localized renal masses treated with different approaches (open [O], laparoscopic [L], and percutaneous [P]) and modalities (radical nephrectomy [RN], nephron sparing surgery [NSS] and cryoablation [CA]). The SF-36, Functional Assessment of Cancer Therapy-Kidney Symptom Index-15 questionnaires and pain visual analog scale were completed pretreatment and at 1, 3, and 12 months posttreatment. Questionnaire results were stratified according to approach and treatment modality using a longitudinal multilevel linear regression model. Clinical patient and tumor characteristics, complications, and histopathology results were tested as confounders. RESULTS: Ninety eight patients completed baseline and at least one follow-up questionnaires; 27.5%, 16.3%, 22.5%, 9.2%, 13.3%, and 11.2% patients received LNSS, ONSS, LRN, ORN, LCA, and PCA, respectively. Higher baseline SF-36 (3 domains) and Functional Assessment of Cancer Therapy-Kidney Symptom Index-15 scores were reported in L group compared with the O approach. Overall, HRQoL decreased at 1 month and gradually normalized to baseline level or higher at 1 year. For treatment modality at baseline, higher mean visual analog scale was observed in CA than RN group. A trend to decreased HRQoL was observed at 1 month for RN and NSS; thereafter, scores normalized to baseline levels or higher. Approach or treatment modality HRQoL did not change substantially when corrected for confounders. CONCLUSION: At short-term, HRQoL outcome favored minimally invasive treatment of RCC; at mid-term, these advantages were no longer apparent. This suggest that in selecting the best surgical treatment for the patient, oncological outcome should be the primary consideration as both approach and treatment modality result in similar HRQoL outcomes.

Diagnostic accuracy of 68 Ga-prostate-specific membrane antigen (PSMA) positron-emission tomography (PET) and multiparametric (mp)MRI to detect intermediate-grade intra-prostatic prostate cancer using whole-mount pathology: impact of the addition of 68 Ga-PSMA PET to mpMRI.

OBJECTIVE: To evaluate the ability of prostate-specific membrane antigen (PSMA)-positron-emission tomography (PET)/computed tomography (CT) to detect intermediate-grade intra-prostatic prostate cancer (PCa), and to determine if PSMA-PET improves the diagnostic accuracy of multiparametric magnetic resonance imaging (mpMRI). PATIENTS AND METHODS: A total of 56 consecutive patients with International Society of Urological Pathology (ISUP) grade 2-3 PCa after radical prostatectomy, who underwent both mpMRI and PSMA-PET CT (hereafter PSMA-PET) preoperatively, were enrolled in this study. The accuracy of PSMA-PET, mpMRI alone, and the two procedures in combination was analysed for identifying ISUP grades 1-3 within a 12-segment model. The accuracy of a combined predictive model (PSMA-PET and mpMRI) was determined. Receiver-operating characteristic curve analysis to determine the optimal standardized uptake value (SUVmax ) for PSMA-PET in discriminating between ISUP grades 1 and ≥2 was performed. RESULTS: On a per-patient basis, the sensitivities for PSMA-PET and mpMRI in identifying ISUP grades 2-3 PCa were 100% and 97%, respectively. Assessing ISUP grade ≥2 PCa using a 12-segment analysis, PSMA-PET demonstrated greater diagnostic accuracy (area under the curve), sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV), with values of 0.91, 88%, 93%, 95% and 85%, respectively, than did mpMRI (Prostate Imaging Reporting and Data System [PI-RADS] 3-5), at 0.79, 68%, 91%, 87%, and 75%, respectively. When used in combination (PSMA-PET and mpMRI PIRADS 4-5), sensitivity, specificity, NPV and PPV were 92%, 90%, 96% and 81%, respectively. The sensitivity for both techniques reduced markedly when assessing ISUP grade 1 PCa (18% for PSMA-PET, 10% for mpMRI). An SUVmax value of 3.95 resulted in 94% sensitivity and 100% specificity. CONCLUSION: PSMA-PET is accurate in detecting segments containing intermediate-grade intra-prostatic PCa (ISUP grade ≥ 2), compared with and complementary to mpMRI. By contrast the detection rate for ISUP grade 1 disease for both PSMA-PET and mpMRI was low.

Does adherence to treatment mediate the relationship between patients' treatment outcome expectancies and the outcomes of pain intensity and recovery from acute low back pain?

It is believed that patients' expectancies about the effectiveness of treatment influence their treatment outcomes, but the working mechanism is rarely studied in patients with low back pain. Theoretical models suggest that adherence to treatment may be an important pathway. The aim of this study was to assess the mediating role of adherence to treatment in the relationship between expectancies and the outcomes of recovery and pain intensity in patients with acute low back pain. This study used data from a randomized placebo-controlled trial of paracetamol for acute low back pain. Expectancies were measured with the Credibility Expectancy Questionnaire. Adherence was measured with a medication diary. Pain intensity was recorded daily in a diary on a 0 to 10 pain scale, and recovery was defined as the first of 7 consecutive days scoring 0 or 1 on a 6-point pain scale. Cox regression (dependent variable: recovery) and linear mixed-model analyses (dependent variable: daily pain intensity scores) were performed. The "difference in coefficients" approach was used to establish mediation. A total of 1573 participants were included in current analyses. There was a small but highly significant relationship between expectancies and outcomes; 3.3% of the relationship between expectancies and recovery and 14.2% of the relationship between expectancies and pain intensity were mediated by adherence to treatment. This study does not convincingly support the theory that adherence is a key pathway in the relationship between treatment outcome expectancies and recovery and pain intensity in this acute low back pain population.

A new approach to analyse longitudinal epidemiological data with an excess of zeros.

BACKGROUND: Within longitudinal epidemiological research, 'count' outcome variables with an excess of zeros frequently occur. Although these outcomes are frequently analysed with a linear mixed model, or a Poisson mixed model, a two-part mixed model would be better in analysing outcome variables with an excess of zeros. Therefore, objective of this paper was to introduce the relatively 'new' method of two-part joint regression modelling in longitudinal data analysis for outcome variables with an excess of zeros, and to compare the performance of this method to current approaches. METHODS: Within an observational longitudinal dataset, we compared three techniques; two 'standard' approaches (a linear mixed model, and a Poisson mixed model), and a two-part joint mixed model (a binomial/Poisson mixed distribution model), including random intercepts and random slopes. Model fit indicators, and differences between predicted and observed values were used for comparisons. The analyses were performed with STATA using the GLLAMM procedure. RESULTS: Regarding the random intercept models, the two-part joint mixed model (binomial/Poisson) performed best. Adding random slopes for time to the models changed the sign of the regression coefficient for both the Poisson mixed model and the two-part joint mixed model (binomial/Poisson) and resulted into a much better fit. CONCLUSION: This paper showed that a two-part joint mixed model is a more appropriate method to analyse longitudinal data with an excess of zeros compared to a linear mixed model and a Poisson mixed model. However, in a model with random slopes for time a Poisson mixed model also performed remarkably well.