Expect the unexpected: investigating discordant prostate MRI and biopsy results.

OBJECTIVES: To evaluate discrepant radio-pathological outcomes in biopsy-naïve patients undergoing prostate MRI and to provide insights into the underlying causes. MATERIALS AND METHODS: A retrospective analysis was conducted on 2780 biopsy-naïve patients undergoing prostate MRI at a tertiary referral centre between October 2015 and June 2022. Exclusion criteria were biopsy not performed, indeterminate MRI findings (PI-RADS 3), and clinically insignificant PCa (Gleason score 3 + 3). Patients with discrepant findings between MRI and biopsy results were categorised into two groups: MRI-negative/Biopsy-positive and MRI-positive/Biopsy-negative (biopsy-positive defined as Gleason score ≥ 3 + 4). An expert uroradiologist reviewed discrepant cases, retrospectively re-assigning PI-RADS scores, identifying any missed MRI targets, and evaluating the quality of MRI scans. Potential explanations for discrepancies included MRI overcalls (including known pitfalls), benign pathology findings, and biopsy targeting errors. RESULTS: Patients who did not undergo biopsy (n = 1258) or who had indeterminate MRI findings (n = 204), as well as those with clinically insignificant PCa (n = 216), were excluded, with a total of 1102 patients analysed. Of these, 32/1,102 (3%) were classified as MRI-negative/biopsy-positive and 117/1102 (11%) as MRI-positive/biopsy-negative. In the MRI-negative/Biopsy-positive group, 44% of studies were considered non-diagnostic quality. Upon retrospective image review, target lesions were identified in 28% of cases. In the MRI-positive/Biopsy-negative group, 42% of cases were considered to be MRI overcalls, and 32% had an explanatory benign pathological finding, with biopsy targeting errors accounting for 11% of cases. CONCLUSION: Prostate MRI demonstrated a high diagnostic accuracy, with low occurrences of discrepant findings as defined. Common reasons for MRI-positive/Biopsy-negative cases included explanatory benign findings and MRI overcalls. CLINICAL RELEVANCE STATEMENT: This study highlights the importance of optimal prostate MRI image quality and expertise in reducing diagnostic errors, improving patient outcomes, and guiding appropriate management decisions in the prostate cancer diagnostic pathway. KEY POINTS: • Discrepancies between prostate MRI and biopsy results can occur, with higher numbers of MRI-positive/biopsy-negative relative to MRI-negative/biopsy-positive cases. • MRI-positive/biopsy-negative cases were mostly overcalls or explainable by benign biopsy findings. • In about one-third of MRI-negative/biopsy-positive cases, a target lesion was retrospectively identified.

The PRECISE Recommendations for Prostate MRI in Patients on Active Surveillance for Prostate Cancer: A Critical Review.

The Prostate Cancer Radiological Estimation of Change in Sequential Evaluation (PRECISE) recommendations were published in 2016 to standardize the reporting of MRI examinations performed to assess for disease progression in patients on active surveillance for prostate cancer. Although a limited number of studies have reported outcomes from use of PRECISE in clinical practice, the available studies have demonstrated PRECISE to have high pooled NPV but low pooled PPV for predicting progression. Our experience in using PRECISE in clinical practice at two teaching hospitals has highlighted issues with its application and areas requiring clarification. This Clinical Perspective critically appraises PRECISE on the basis of this experience, focusing on the system's key advantages and disadvantages and exploring potential changes to improve the system's utility. These changes include consideration of image quality when applying PRECISE scoring, incorporation of quantitative thresholds for disease progression, adoption of a PRECISE 3F sub-category for progression not qualifying as substantial, and comparisons with both the baseline and most recent prior examinations. Items requiring clarification include derivation of a patient-level score in patients with multiple lesions, intended application of PRECISE score 5 (i.e., if requiring development of disease that is no longer organ-confined), and categorization of new lesions in patients with prior MRI-invisible disease.

Using a Recurrent Neural Network To Inform the Use of Prostate-specific Antigen (PSA) and PSA Density for Dynamic Monitoring of the Risk of Prostate Cancer Progression on Active Surveillance.

The global uptake of prostate cancer (PCa) active surveillance (AS) is steadily increasing. While prostate-specific antigen density (PSAD) is an important baseline predictor of PCa progression on AS, there is a scarcity of recommendations on its use in follow-up. In particular, the best way of measuring PSAD is unclear. One approach would be to use the baseline gland volume (BGV) as a denominator in all calculations throughout AS (nonadaptive PSAD, PSADNA), while another would be to remeasure gland volume at each new magnetic resonance imaging scan (adaptive PSAD, PSADA). In addition, little is known about the predictive value of serial PSAD in comparison to PSA. We applied a long short-term memory recurrent neural network to an AS cohort of 332 patients and found that serial PSADNA significantly outperformed both PSADA and PSA for follow-up prediction of PCa progression because of its high sensitivity. Importantly, while PSADNA was superior in patients with smaller glands (BGV ≤55 ml), serial PSA was better in men with larger prostates of >55 ml. Patient summary: Repeat measurements of prostate-specific antigen (PSA) and PSA density (PSAD) are the mainstay of active surveillance in prostate cancer. Our study suggests that in patients with a prostate gland of 55 ml or smaller, PSAD measurements are a better predictor of tumour progression, whereas men with a larger gland may benefit more from PSA monitoring.

Normal variations in position and relations of the median nerve in the carpal tunnel: A cross-sectional observational study using clinical magnetic resonance imaging.

A standard relationship of the median nerve to neighboring tendons in the carpal tunnel has been described, but descriptions of normal variations are limited. The aim of this study is to describe the variation in position of the median nerve within the carpal tunnel and the variability in relation to adjacent tendons on clinical MR studies. A retrospective study was performed, analyzing 37 wrist MR examinations performed on a 3T MR machine. Primary endpoints involved measuring the four coordinates of the median nerve in relation to anatomical bony landmarks performed on a single-slice image. The secondary endpoints were anterior, posterior, medial, and lateral relations of the median nerve. The mean distance from hook of hamate to trapezium was 21.8 mm with a mean depth of 9.6 mm. The mean position of the median nerve from the hook of the hamate was 12.5 mm with a depth of 2.9 mm. The most common radial relations to the median nerve in descending order of frequencies were FPL, FDS 2, and FDS 3, the most common dorsal relations were FDS 2 and then FDS 3, and the most common ulnar relations were FDS 3 and then FDS 2. The position of the median nerve in the carpal tunnel is variable both in ulna-to-radial and dorsal to palmar directions, and variations in relation to neighboring tendons are also common. Clin. Anat. 33:598-604, 2020. © 2019 Wiley Periodicals, Inc.

'Stent in a stent'--an alternative technique for removing partially covered stents following sleeve gastrectomy complications.

Endoscopic stenting is a relatively new technique for the treatment of post sleeve gastrectomy complications. Partially covered stents are used in this method to minimise the risk of migration but they are associated with difficulties with removal. Patients requiring emergency stenting following sleeve gastrectomy underwent insertion of a partially covered metallic stent. One month later, if the stent was not easily removable, a fully covered overlapping stent was inserted and the patient was readmitted 2 weeks later for removal of both stents. Four patients required stenting following sleeve gastrectomy leaks, and one patient required stenting for a stricture. In these cases, a 'stent in a stent' technique was used for removal. This technique allows the safe removal of partially covered stents inserted following sleeve gastrectomy complications.

Simultaneous intra-gastric balloon removal and laparoscopic sleeve gastrectomy for the super-super obese patients--a prospective feasibility study.

BACKGROUND: The aim of the study was to prospectively evaluate the feasibility and clinical efficacy of a strategy of performing simultaneous balloon removal and sleeve gastrectomy in the super-super obese patients. METHODS: Forty consecutive super-super obese patients underwent intra-gastric balloon insertion followed by simultaneous balloon removal and sleeve gastrectomy 6 months later. RESULTS: Balloon insertion resulted in a reduction in mean body mass index from 69.3 ± 1.4 to 62.3 ± 1.3 kg/m2. Simultaneous balloon removal and sleeve gastrectomy was achieved in 39 cases. There were no operative mortality and no leaks. Six months following sleeve gastrectomy, the mean BMI of the cohort had fallen to 54.1 ± 1.2 kg/m2. CONCLUSIONS: Simultaneous balloon removal and sleeve gastrectomy in the super-super obese patients is feasible as a single-stage procedure with good perioperative outcomes.

Does closure of the mesenteric defects during antecolic laparoscopic gastric bypass for morbid obesity reduce the incidence of symptomatic internal herniation?

A best evidence topic in surgery was written according to a structured protocol. The question asked was whether the closure of the mesenteric defects during laparoscopic gastric bypass via antecolic approach for morbid obesity reduces the incidence of symptomatic internal herniation. 251 papers were found using the reported search strategy of which three papers best represented the answer to the question. All three studies showed that by closuring the mesenteric defects, resulted in a reduction in the incidence of symptomatic internal hernias. One study showed there to be new complications arising from primary closure, but this was undetermined statistically. The evidence still however remains limited regarding the need for closure of mesenteric defects in gastric bypass operations. We recommend there is a need for large scale randomized control trials with suitable follow up for patients.

A two-state model for Ca2+/CaM-dependent protein kinase II (alphaCaMKII) in response to persistent Ca2+ stimulation in hippocampal neurons.

Persistent elevation of the intracellular free Ca(2+) concentration [Ca(2+)](i) is neurotoxic and therefore it is important to understand how it affects downstream components of the Ca(2+) signaling pathway. The response of calmodulin (CaM) and alphaCa(2+)/CaM-dependent protein kinase II (alphaCaMKII), to intracellular Ca(2+) overload in hippocampal neurons is studied by confocal imaging of fluorescently tagged proteins. Transient and persistent redistribution of CaM and alphaCaMKII together is seen from the cytosol to dendritic and somatic punctae. Typical persistent redistribution occurs following a lag of 138+/-(S.E.M.) 12 s and is complete at 460+/-(S.E.M.) 34 s (n=18), lack of Thr(286)-autophosphorylation of alphaCaMKII however promotes the formation of early transient punctae (peak at 40 s). In contrast, the T286D-mimick of phospho-Thr(286)-alphaCaMKII forms punctae with a delay >10 min, indicating that Thr(286)-autophosphorylation is antagonistic to CaMKII clustering. A two-state model is proposed in which phospho-Thr(286)-alphaCaMKII, formed immediately upon Ca(2+) stimulation, is primarily responsible for target interactions and memory functions of alphaCaMKII. However, a distinct clustering form denoted alphaCaMKII(c), generated upon persistent intracellular free Ca(2+) elevation, is deposited in the punctae which are made of self-interacting CaM/CaMKII complexes. Punctate deposition disables both the interactions and the activity of CaMKII.