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.

A Systematic Review of Radiation-Related Lymphopenia in Genito-urinary Malignancies.

BACKGROUND: The impact of radiation-related lymphopenia on clinical outcomes has been reported in various solid malignancies such as high grade gliomas, head and neck cancers, thoracic malignancies and gastro-intestinal malignancies but its impact is not clearly known in the context of common genito-urinary (GU) malignancies. METHODOLOGY: To better understand the effect of radiation-associated lymphopenia in prostate and bladder cancer, we undertook this systematic review of clinical studies that have studied radiation-related lymphopenia in GU malignancies. A systematic methodology search of PubMed, Embase, and Cochrane library resulted in 2125 abstracts. Ten studies fulfilled the inclusion criteria which included any prospective, retrospective study or cohort study of prostate, urinary bladder, kidney, ureter, urethra, penile cancer in humans, and radiation should be part of treatment and intent has to be in definitive or adjuvant settings. Finally the study should have data on radiation-related lymphopenia. RESULTS: Four studies reported on the cancer-specific outcomes related to the lymphopenia. The incidence of low lymphocyte counts were documented in all the studies. Three studies analyzed the factors associated with the Lymphocyte depletion. Pooled incidence of severe lymphopenia was 29.25% and mild to moderate lymphopenia was 60.75%. Bone marrow volume receiving 40 Gy was associated with the incidence of lymphopenia. CONCLUSION: One-third of the patients suffer from severe lymphopenia after radiation in prostate and bladder cancer. There are no clear data to support the correlation between severe lymphopenia and disease outcomes. Bone marrow dosimetry can affect the incidence and severity of lymphopenia. There is need of prospective datasets to identify the impact of radiation-related lymphopenia in GU malignancies focusing on long-term side effects, recurrence rates, and overall survival.

Risk stratification of prostate cancer with MRI and prostate-specific antigen density-based tool for personalized decision making.

OBJECTIVES: MRI is now established for initial prostate cancer diagnosis; however, there is no standardized pathway to avoid unnecessary biopsy in low-risk patients. Our study aimed to test previously proposed MRI-focussed and risk-adapted biopsy decision models on a real-world dataset. METHODS: Single-centre retrospective study performed on 2055 biopsy naïve patients undergoing MRI. Diagnostic pathways included "biopsy all", "MRI-focussed" and two risk-based MRI-directed pathways. Risk thresholds were based on prostate-specific antigen (PSA) density as low (<0.10 ng mL-2), intermediate (0.10-0.15 ng mL-2), high (0.15-0.20 ng mL-2), or very high-risk (>0.20 ng mL-2). The outcome measures included rates of biopsy avoidance, detection of clinically significant prostate cancer (csPCa), missed csPCa, and overdiagnosis of insignificant prostate cancer (iPCa). RESULTS: Overall cancer rate was 39.9% (819/2055), with csPCa (Grade-Group ≥2) detection of 30.3% (623/2055). In men with a negative MRI (Prostate Imaging-Reporting and Data System, PI-RADS 1-2), the risk of cancer was 1.2%, 2.6%, 9.0%, and 12.9% in the low, intermediate, high, and very high groups, respectively; for PI-RADS score 3 lesions, the rates were 10.5%, 14.3%, 25.0%, and 33.3%, respectively. MRI-guided pathway and risk-based pathway with a low threshold missed only 1.6% csPCa with a biopsy-avoidance rate of 54.4%, and the risk-based pathway with a higher threshold avoided 62.9% (1292/2055) of biopsies with 2.9% (61/2055) missed csPCa detection. Decision curve analysis found that the "risk-based low threshold" pathway has the highest net benefit for probability thresholds between 3.6% and 13.9%. CONCLUSION: Combined MRI and PSA-density risk-based pathways can be a helpful decision-making tool enabling high csPCa detection rates with the benefit of biopsy avoidance and reduced iPCa detection. ADVANCES IN KNOWLEDGE: This real-world dataset from a large UK-based cohort confirms that combining MRI scoring with PSA density for risk stratification enables safe biopsy avoidance and limits the over-diagnosis of insignificant cancers.

Median arcuate ligament syndrome diagnosis on Computed Tomography: what a radiologist needs to know.

Median arcuate ligament syndrome or celiac artery compression syndrome is one of the abdominal vascular compression syndromes due to compression of proximal celiac artery by the median arcuate ligament. The median arcuate ligament unites diaphragmatic crura on either side at the level of aortic hiatus. The ligament has a low insertion causing compression of the celiac artery resulting in clinical symptoms of postprandial pain and weight loss. It is a rare syndrome, detected incidentally on routine Computed Tomography abdomen and pelvis studies. We present a rare case of a 35-year-old female who presented with abdominal pain. She was evaluated by Computed Tomography scan of the abdomen and pelvis. Ultrasound Doppler of mesenteric vasculature helped detect celiac artery stenosis. A referral to the vascular surgery department was made; however, the patient was managed conservatively.

Malakoplakia presenting as Pleuropulmonary masses: A rare clinical, radiological and histopathological diagnosis.

Pleuropulmonary malakoplakia is a rare granulomatous inflammatory condition characterized by the accumulation of histiocytes that contain basophilic inclusions called Michaelis-Gutmann bodies . It is usually reported in patients with acquired immunodeficiency syndrome. We present clinical, radiological, pathological features and management of a rare case of pulmonary malakoplakia in an immunocompetent male patient with a past history of empyema treated with surgical decortication. Clinically, the patient presented with shortness of breath, productive cough and lethargy. On imaging, Computed Tomography of Thorax showed multiple nodular lung masses and nodular pleural thickening with marked Fluorodeoxyglucose Positron Emission Tomography avidity raising suspicion of advanced pulmonary malignancy. Characteristic Michaelis-Gutmann bodies were identified on histopathology, confirming the diagnosis of malakoplakia. The patient was medically managed with a long course of antibiotics. On follow-up, there was a significant clinical and radiological improvement. Pulmonary malakoplakia is a rare entity, with very few cases reported worldwide, and even fewer in immunocompetent individuals.

A case of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) presenting as post-infectious manifestation of SARS-CoV-2 infection.

White matter hyperintensities (WMHs) lacunar infarcts and cerebral microbleeds are well-established features associated with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). Increasing case reports and series recounts a wide array of neurological manifestations of COVID-19 including acute cerebrovascular disease, encephalopathy, encephalitis and demyelination. Recently association between COVID-19 and CADASIL has been identified. We describe an unusual case of CADASIL diagnosed as a possible post-infectious manifestation of COVID-19 patient with imaging features closely resembling post-infectious encephalomyelitis.