Does lateral extra-articular tenodesis affect knee stability in cases with isolated anterior cruciate ligament reconstruction?

Objective: The purpose of this randomised controlled trial was to assess the effect on knee function and stabilising effectiveness of lateral extra-articular tenodesis (LET) in anterior cruciate ligament (ACL) restoration. Methods: A prospective randomised clinical study that compared the functional outcomes of two groups-one undergoing anatomic single bundle ACL reconstruction (ASB-ACLR) with ilio-tibial band tenodesis (LET) for 20 patients, and the other undergoing ASB-ACLR-was carried out between February 2020 and August 2022. Results: By combining Lateral Extra-articular Tenodesis (LET) with intra-articular Anterior Cruciate Ligament Reconstruction (ACLR), our study observed a significant reduction in the occurrence of high-grade pivot-shift phenomena. Prior to surgery, both Groups A and B exhibited graded (D) pivot-shift test results. However, post-surgery, the pivot-shift test yielded negative results in 60% of patients in Group A and 90% of patients in Group B. The statistical analysis revealed a notable difference between the two groups, as indicated by a P-value of 0.003. Upon conducting a brief follow-up, we evaluated the Lysholm score, and anterior knee stability of ACLR with LET, finding no statistically significant difference compared to those of single ACLR. The Lachman tests also revealed no significant disparity between the two groups (p = 0.106). Analyzing the Lysholm scores in Group A and Group B, we observed an increase to 90.70% and 91.10%, respectively. Conclusion: Rotational stability is much improved when lateral extra-articular tenodesis (LET) utilizing the ilio-tibial band as an augmentation is used in ACL restoration. Especially useful for high-grade pivot-shift phenomena is this technique.

The ACGIH TLV for lifting: Estimated TLVs for torso asymmetry beyond 30 degrees.

BACKGROUND: The American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Values (TLVs) for Lifting is a manual material handling (MMH) assessment method to identify weight limits that nearly all workers may be exposed to without developing work-related low back disorders (LBD). However, this assessment method only applies to lifting with the torso within 30° asymmetry of the sagittal plane. OBJECTIVE: Estimate TLV weight limits while lifting with torso asymmetry greater than 30° beyond the sagittal plane. METHODS: Lifting tasks were performed from various horizontal and vertical locations, at torso asymmetry angles of 0°, 15°, 30°, 45°, 60°, 75° and 90°, using ACGIH identified TLVs. Validated MMH assessment methods (NIOSH Lifting Equation, Ohio State University LBD Risk Model) were utilized to estimate TLVs at torso asymmetries greater than 30°. RESULTS: The current ACGIH TLVs resulted in low- to moderate-risk risk levels for torso asymmetries from 0° to 30°, and the risk incrementally increased as torso asymmetry increased to 90°. With the intention to keep the risk levels to that found at 30° torso asymmetry, lower TLV weight limits in the vertical and horizontal zones investigated were estimated for torso asymmetries from 45° to 90°. The resulting adjusted TLVs were consistent with weight limits identified for similar lifting conditions from other assessment methods that account for torso asymmetry. CONCLUSIONS: This research found current ACGIH-defined TLVs possess less than high-risk for LBD, and provided guidance to practitioners for reduced TLVs when torso asymmetry is greater than 30° from the sagittal plane.

Hybrid Oncocytic Tumors (HOTs) in Birt-Hogg-Dubé Syndrome Patients-A Tale of Two Cities: Sequencing Analysis Reveals Dual Lineage Markers Capturing the 2 Cellular Populations of HOT.

Birt-Hogg-Dubé (BHD) syndrome is associated with an increased risk of multifocal renal tumors, including hybrid oncocytic tumor (HOT) and chromophobe renal cell carcinoma (chRCC). HOT exhibits heterogenous histologic features overlapping with chRCC and benign renal oncocytoma, posing challenges in diagnosis of HOT and renal tumor entities resembling HOT. In this study, we performed integrative analysis of bulk and single-cell RNA sequencing data from renal tumors and normal kidney tissues, and nominated candidate biomarkers of HOT, L1CAM, and LINC01187 , which are also lineage-specific markers labeling the principal cell and intercalated cell lineages of the distal nephron, respectively. Our findings indicate the principal cell lineage marker L1CAM and intercalated cell lineage marker LINC01187 to be expressed mutually exclusively in a unique checkered pattern in BHD-associated HOTs, and these 2 lineage markers collectively capture the 2 distinct tumor epithelial populations seen to co-exist morphologically in HOTs. We further confirmed that the unique checkered expression pattern of L1CAM and LINC01187 distinguished HOT from chRCC, renal oncocytoma, and other major and rare renal cell carcinoma subtypes. We also characterized the histopathologic features and immunophenotypic features of oncocytosis in the background kidney of patients with BHD, as well as the intertumor and intratumor heterogeneity seen within HOT. We suggest that L1CAM and LINC01187 can serve as stand-alone diagnostic markers or as a panel for the diagnosis of HOT. These lineage markers will inform future studies on the evolution and interaction between the 2 transcriptionally distinct tumor epithelial populations in such tumors.

Comparison of ACGIH lifting threshold limit values to validated low back disorder lifting assessment methods outcomes.

BACKGROUND: Work-related low back pain (LBP) increases the workforce disability and healthcare costs. This study evaluated the LBD risk level associated with handling the ACGIH TLVs in lifting tasks corresponding to various horizontal and vertical zones. OBJECTIVE: The aim of this study was to compare the low-risk ACGIH TLV to risk outcomes from various validated lifting assessment methods, including the OSU LBD Risk Model, NIOSH Lifting Equation, and LiFFT. METHODS: Twenty-four subjects were recruited for this study to perform various lifting conditions. The various ergonomic assessment methods were then used to obtain the risk assessment outcomes. RESULTS: The selected assessment methods showed that the ACGIH-defined TLVs are associated with less than high-risk for LBD for all the assessed tasks. The findings showed a moderate agreement (Kendall's W = 0.477) among the various assessment methods risk outcomes. The highest correlation (ρ= 0.886) was observed between the NIOSH Lifting Equation and LiFFT methods risk assessment outcomes. CONCLUSION: The findings showed that ACGIH-defined TLVs possesses less than high-risk for LBD. The outcomes of the selected ergonomic assessment methods moderately agree to each other.

Use of a physical activity monitor to track perioperative activity of radical cystectomy patients. Our first glimpse at what our patients are doing before and after surgery.

PURPOSE: To optimize recovery after radical cystectomy (RC), providers stress the importance of ambulation and adequate rest. However, little is known about the activity and sleep habits of patients undergoing RC. Therefore, we utilized a wearable physical activity monitor (PAM) in the perioperative period to provide the first objective data on physical activity and sleep habits for RC patients. MATERIALS AND METHODS: We prospectively identified patients ≥60 years old with planned RC. Participants completed a 4-week prehabilitation exercise program prior to surgery. They wore a PAM for 7-day intervals: at baseline, after prehabilitation, at postoperative day (POD) 30 and POD90. We tracked physical activity via metabolic equivalents (METs). METs were categorized by intensity: light (MET 1.5-<3), moderate (MET 3-<6), and vigorous (MET ≥6). We calculated daily step totals. We tracked hours slept and number of sleep awakenings. We correlated activity and sleep with self-reported quality of life (QOL). RESULTS: Forty-two patients completed prehabilitation and RC. Moderate intensity exercise decreased at POD30 (61 minutes/d at baseline, 30 minutes/d at POD30, P = 0.005). Physical activity did not significantly differ for light or vigorous activity at any timepoint. RC did not significantly affect sleep. Sleep and physical activity were associated with mental and physical QOL, respectively. CONCLUSIONS: This is the first study utilizing patient-worn monitors in RC to track physical activity and sleep. This study gives patients and providers a better understanding of postcystectomy recovery expectations. With these results in mind, interventions may be implemented to optimize activity and sleep in the perioperative period.

Characterization of Intercalated Cell Markers KIT and LINC01187 in Chromophobe Renal Cell Carcinoma and Other Renal Neoplasms.

Introduction. Chromophobe renal cell carcinoma (chromophobe RCC) is the third major subcategory of renal tumors after clear cell RCC and papillary RCC, accounting for approximately 5% of all RCC subtypes. Other oncocytic neoplasms seen commonly in surgical pathology practice include the eosinophilic variant of chromophobe RCC, renal oncocytoma, and low-grade oncocytic unclassified RCC. Methods. In our recent next-generation sequencing based study, we nominated a lineage-specific novel biomarker LINC01187 (long intergenic non-protein coding RNA 1187) which was found to be enriched in chromophobe RCC. Like KIT (cluster of differentiation 117; CD117), a clinically utilized chromophobe RCC related biomarker, LINC01187 is expressed in intercalated cells of the nephron. In this follow-up study, we performed KIT immunohistochemistry and LINC01187 RNA in situ hybridization (RNA-ISH) on a cohort of chromophobe RCC and other renal neoplasms, characterized the expression patterns, and quantified the expression signals of the two biomarkers in both primary and metastatic settings. Results. LINC01187, in comparison to KIT, exhibits stronger and more uniform expression within tumors while maintaining temporal and spatial consistency. LINC01187 also is devoid of intra-tumoral heterogeneous expression pattern, a phenomenon commonly noted with KIT. Conclusions. LINC01187 expression can augment the currently utilized KIT assay and help facilitate easy microscopic analyses in routine surgical pathology practice.

Deciphering intratumor heterogeneity in clear cell renal cell carcinoma utilizing clinicopathologic and molecular platforms.

Clear cell renal cell carcinoma (CCRCC) is a common renal malignancy known for its lethality and chromosome 3p aberrancies associated with loss of VHL. It has been shown that additional prognostic molecular markers exist in other transcriptional modifiers such as BAP1 and SETD2. Molecular heterogeneity has been described between primary and metastatic sites as well as genetic diversity in spatial tumor analysis; however, morphologic and proteogenomic heterogeneity information is lacking. We assessed 77 nephrectomy specimens with a diagnosis of CCRCC for morphologic architectural patterns including nodular growth patterns and variations in WHO/ISUP grade. Evaluation of highly heterogeneous areas with immunohistochemical (IHC) staining for BAP1, UCHL1, SETD2, and CAIX was performed and correlated with morphologic and histology data. Ultimately, high variability in the morphologic and histological findings matched the complexity of the IHC findings. Alterations in expression of CAIX and UCHL1 correlated with alterations in transcriptional regulators BAP1 and SETD2 within the tumor. High-grade morphology, such as eosinophilia, were areas enriched for alteration of biomarker expression. This highly complex data set of morphologic and biomarker characteristics highlights the heterogeneity of morphology amongst high-grade CCRCC tumors.

Occupational discomfort and injuries among automotive technicians in Jeddah, Saudi Arabia: A cross-sectional study.

BACKGROUND: Work-related musculoskeletal disorders (WMSDs) are one of the major causes of disability and early retirement. Consequently, WMSDs cost businesses billions of dollars annually due to compensation claims and productivity loss. Automotive technicians are vulnerable to WMSDs due to the nature of their work, which exposes them to numerous WMSDs risk factors. OBJECTIVE: This cross-sectional study aimed to evaluate the WMSD cases among technicians and evaluate their postures while working in small automotive repair shops in Jeddah, Saudi Arabia (SA). METHODS: The study employed a cross-sectional design. A self-administrated questionnaire and body parts discomfort survey were filled by thirty automotive technicians. A postural analysis technique was performed to assess the body postures that technicians adopt while performing the tasks, in order to estimate the associated risk of WMSD discomfort. RESULTS: Most automotive technicians suffer severe pain in the lower back, shoulders, neck, hands or wrists, and knees. The technicians related the pain to awkward body postures, heavy lifting, and sustained forceful movements. CONCLUSION: Automotive technicians are advised to level the height of the work surface as feasible, to work as close as possible to said work surface, and to avoid working with awkward body postures as much as possible.

TERT Promoter Mutations in Keratinizing and Nonkeratinizing Squamous Metaplasia of the Urinary Tract.

We identified urothelial tract biopsy and resection specimens with keratinizing squamous metaplasia (KSM), nonkeratinizing squamous metaplasia (NKSM), and urothelial and squamous carcinomas over a 20-yr period, focusing on cases with neurogenic lower urinary tract dysfunction (NLUTD) and/or those with spatial or temporal variation in sampling. TERT promoter mutations as assessed via allele-specific polymerase chain reaction were surprisingly common in our testing cohort, identified not only in 15 (94%) invasive cancer foci but also in 13 (68%) examples of KSM and seven (70%) examples of NKSM. TERT promoter mutations were present in 23 foci from NLUTD specimens and 11 foci from bladder diverticula, including in foci of KSM, NKSM, and unremarkable urothelium from cases with no clinical association with previous, concurrent, or subsequent cancer. Our demonstration of temporally and spatially persistent TERT promoter mutation in examples of KSM and NKSM in cases of bladder cancer and in morphologically benign cases with neurogenic dysfunction suggests a molecular mechanism by which such pre-neoplastic lesions can potentially progress and develop into overt carcinoma. Given the interest in TERT promoter mutations as a potential biomarker for the development of bladder cancer, these findings possibly explain the association between conditions with chronic urinary bladder injury (such as the natural history of NLUTD) and higher risk of bladder cancer. TERT promoter mutations may represent an early event in bladder cancer tumorogenesis, and our findings expand on the clinical ramifications and predictive value of TERT promoter mutations in this context. PATIENT SUMMARY: Mutations in the TERT gene are the most common genetic changes in bladder cancer. We found that these mutations are also sometimes present in patients with chronic bladder irritation such as neurogenic bladder dysfunction and changes to the lining of the bladder that pathologists would consider "benign." This finding might explain why such conditions are associated with the development of bladder cancer.

Genetic risk assessment for hereditary renal cell carcinoma: Clinical consensus statement.

BACKGROUND: Although renal cell carcinoma (RCC) is believed to have a strong hereditary component, there is a paucity of published guidelines for genetic risk assessment. A panel of experts was convened to gauge current opinions. METHODS: A North American multidisciplinary panel with expertise in hereditary RCC, including urologists, medical oncologists, clinical geneticists, genetic counselors, and patient advocates, was convened. Before the summit, a modified Delphi methodology was used to generate, review, and curate a set of consensus questions regarding RCC genetic risk assessment. Uniform consensus was defined as ≥85% agreement on particular questions. RESULTS: Thirty-three panelists, including urologists (n = 13), medical oncologists (n = 12), genetic counselors and clinical geneticists (n = 6), and patient advocates (n = 2), reviewed 53 curated consensus questions. Uniform consensus was achieved on 30 statements in specific areas that addressed for whom, what, when, and how genetic testing should be performed. Topics of consensus included the family history criteria, which should trigger further assessment, the need for risk assessment in those with bilateral or multifocal disease and/or specific histology, the utility of multigene panel testing, and acceptance of clinician-based counseling and testing by those who have experience with hereditary RCC. CONCLUSIONS: In the first ever consensus panel on RCC genetic risk assessment, 30 consensus statements were reached. Areas that require further research and discussion were also identified, with a second future meeting planned. This consensus statement may provide further guidance for clinicians when considering RCC genetic risk assessment. LAY SUMMARY: The contribution of germline genetics to the development of renal cell carcinoma (RCC) has long been recognized. However, there is a paucity of guidelines to define how and when genetic risk assessment should be performed for patients with known or suspected hereditary RCC. Without guidelines, clinicians struggle to define who requires further evaluation, when risk assessment or testing should be done, which genes should be considered, and how counseling and/or testing should be performed. To this end, a multidisciplinary panel of national experts was convened to gauge current opinion on genetic risk assessment in RCC and to enumerate a set of recommendations to guide clinicians when evaluating individuals with suspected hereditary kidney cancer.

SIMPLifying Urology Residency Operative Assessments: A Pilot Study in Urology Training.

PURPOSE: The Society for Improving Medical Professional Learning (SIMPL) app is an innovative, convenient and validated smartphone-based tool to evaluate residents' operative performance. In this study, we describe the initial implementation of SIMPL in our program's pediatric urology rotation-the first among urology residencies-and provide preliminary data on its adoption by residents and faculty. MATERIALS AND METHODS: Residents and faculty in our pediatric urology division submitted SIMPL evaluations following surgical cases from August 2019 to July 2020. Evaluations consisted of ratings in 3 domains: resident autonomy, resident operative performance and patient-related case complexity. An online survey was also used to gauge attitudes towards SIMPL, describe patterns of use and solicit feedback on areas for improvement. RESULTS: Eight residents and 6 faculty submitted 141 evaluations, with 76.6% of evaluated cases having both faculty and resident ratings. Verbal feedback was included in 94.2%. Faculty-resident agreement ranged from 68.6% to 75.2% (kappa=0.47 to 0.61). Faculty rated postgraduate year (PGY)-4 residents as more autonomous (p=0.040) and higher performing (p=0.028) than PGY-3 residents. All participants agreed that SIMPL was easy to use and compared favorably to existing avenues of feedback. Barriers to implementation included lack of reminders for evaluations and evaluation fatigue. CONCLUSIONS: The SIMPL application improved both frequency and quality of resident operative feedback. Among participants, SIMPL was preferred over the existing feedback system at our institution.

Head to head randomized trial of two decision aids for prostate cancer.

BACKGROUND: While many studies have tested the impact of a decision aid (DA) compared to not receiving any DA, far fewer have tested how different types of DAs affect key outcomes such as treatment choice, patient-provider communication, or decision process/satisfaction. This study tested the impact of a complex medical oriented DA compared to a more simplistic decision aid designed to encourage shared decision making in men with clinically localized prostate cancer. METHODS: 1028 men at 4 VA hospitals were recruited after a scheduled prostate biopsy. Participants completed baseline measures and were randomized to receive either a simple or complex DA. Participants were men with clinically localized cancer (N = 285) by biopsy and who completed a baseline survey. Survey measures: baseline (biopsy); immediately prior to seeing the physician for biopsy results (pre- encounter); one week following the physician visit (post-encounter). Outcome measures included treatment preference and treatment received, knowledge, preference for shared decision making, decision making process, and patients' use and satisfaction with the DA. RESULTS: Participants who received the simple DA had greater interest in shared decision making after reading the DA (p = 0.03), found the DA more helpful (p's < 0.01) and were more likely to be considering watchful waiting (p = 0.03) compared to those receiving the complex DA at Time 2. While these differences were present before patients saw their urologists, there was no difference between groups in the treatment patients received. CONCLUSIONS: The simple DA led to increased desire for shared decision making and for less aggressive treatment. However, these differences disappeared following the physician visit, which appeared to change patients' treatment preferences. Trial registration This trial was pre-registered prior to recruitment of participants.

Understanding the Barriers to Neoadjuvant Chemotherapy in Patients with Muscle Invasive Bladder Cancer: A Quality Improvement Initiative.

PURPOSE: Utilization of neoadjuvant chemotherapy (NAC) for the management of muscle-invasive bladder cancer remains low. We sought to understand our practice of NAC use in order to design a quality improvement initiative geared towards optimizing medical oncology referral. MATERIALS AND METHODS: We identified 339 patients with ≥cT2 bladder cancer treated with radical cystectomy between 2012-2017 at our institution. We assessed the rate of referral to medical oncology, rate of NAC administration, as well as medical, patient and provider variables associated with NAC use. Bayesian logistic regression modeling identified variables associated with NAC use and chart review provided granular patient-level data. RESULTS: 85% (n=289) of patients were referred to medical oncology and 62.5% (n=212) received NAC. Renal insufficiency, hearing loss, and treating urologist were conclusively associated with lower odds of NAC use. 46 patients were not referred to medical oncology and 50% of these had medical contraindications to cisplatin cited as the reason for no referral. 38 patients met with medical oncology but did not receive NAC. 30 (79%) had comorbidities that impacted this decision with 15 (39%) ineligible based on impaired renal function. CONCLUSIONS: Despite the relatively high rates of medical oncology referral and NAC use in this cohort, there are still opportunities to improve the efficiency of this practice. Quality improvement initiatives could optimize the referral of patients with ≥T2 bladder cancer for consideration of cisplatin-based NAC and establish an important quality metric in the management of these patients.

Aligning Urology Residency Training With Real-World Workforce Needs.

OBJECTIVE: Research suggests recently graduated urology residents do not feel ready for independent practice. We conducted a study to determine if Accreditation Council for Graduate Medical Education (ACGME) minimum case requirements, resident case logs, and graduating resident perceived readiness for practice are aligned with the procedural demand and needs of the current urology workforce. DESIGN: Correlative study comparing the association between (1) workforce demand and ACGME case requirements, and (2) workforce demand and perceived resident competency. Three distinct datasets were used; (1) the 2017 Medicare Part B National Summary Data File; (2) the 2017 National Data Report published by the ACGME; and (3) a graduating resident survey from Okhunov et al. SETTING: N/A. PARTICIPANTS: N/A. RESULTS: In 2017, there were a total of 6,784,696 urologic cases performed through Medicare. We found nonsignificant positive associations between resident case logs (rho = 0.16, p = 0.5784), ACGME minimum procedure requirements (rho = 0.42, p = 0.1255), and Medicare procedural demand. Our 15 index procedures accounted for 21.1% (n = 1,431,775) of all Medicare cases, with a median number of 7706 procedures. Endopyelotomy was the least common procedure (n = 98), while cystoscopy was the most common (n = 980,623). Medicare case volume was positively correlated with graduating residents' procedural confidence (r = 0.86, p < 0.0001). We identified four categories with varied alignment of training and demand: (1) high volume and high confidence, (2) high volume and low confidence, (3) low volume and high confidence, and (4) low volume and low confidence. CONCLUSIONS: Optimizing urology residency training is time-sensitive and important. Using national Medicare data coupled with recently graduated urology resident survey results, we provide a guiding framework for improving the alignment of training with workforce demand. Informed by these results, we recommend altering training requirements to reflect these needs.

The Feasibility and Impact of a Presurgical Exercise Intervention Program (Prehabilitation) for Patients Undergoing Cystectomy for Bladder Cancer.

OBJECTIVE: To assess the feasibility of a prehabilitation program for cystectomy patients and to determine the effectiveness of the program in improving strength and functional capacity in the peri-operative period. MATERIALS AND METHODS: This phase I/II study accrued patients ≥60 years old from January 2013 to October 2017 with biopsy-proven bladder cancer, Karnofsky performance score ≥70 and a sedentary baseline lifestyle to participate in a 4-week supervised preoperative exercise training program. Primary outcomes were feasibility and safety; secondary outcomes included changes in fitness, patient-reported QOL, peri-operative complications and readmissions. Student's ttests and Wilcoxon signed-rank test were performed. RESULTS: Fifty-four patients enrolled in the program. Successful completion, defined as patients who began the program and adhered to >70% of the sessions, was attained by 41 of 51 patients (80.4%, 90% CI [71%-90%]). There were no adverse events. Fitness and patient-reported QOL improved postintervention, with sustained improvements in general and mental health 90-days postsurgery. The primary limitation is no control group. CONCLUSION: Prehabilitation prior to cystectomy is feasible, safe, and results in improvements in patient strength, endurance and sustained improvements in patient-reported QOL from baseline. Efforts to further evaluate the impact of prehabilitation in this population in an expanded and randomized fashion are warranted.

Rethinking the one-size-fits-most approach to venous thromboembolism prophylaxis after radical cystectomy.

OBJECTIVES: Empirically dosed enoxaparin is routinely given in the postoperative period for venous thromboembolism (VTE) prophylaxis after radical cystectomy (RC). Patient-specific factors may alter its pharmacokinetics, and it is unclear whether this leads to levels sufficient for antithrombosis. We sought to evaluate variability of anti-factor Xa levels in a cohort of RC patients receiving perioperative enoxaparin prophylaxis. MATERIAL AND METHODS: Patients undergoing RC at a single institution were placed on a postoperative pathway that included enoxaparin. An anti-factor Xa level was drawn 2 to 4 hours after the third dose. The target range for prophylaxis was 0.3 IU/ml to 0.5 IU/ml. RESULTS: The primary outcome was anti-factor Xa level. Demographics, operative time, hospital course, and 30-days post-operative VTE were compared by anti-factor Xa level group using univariate and multivariable analyses. Between January 2018 and 2019, 107 RC patients remained on pathway and were included in our analysis. Sixty-five (61%) were below target range for VTE prophylaxis.  A single VTE event (0.9%) occurred in a subprophylactic individual. The subprophylactic group had a significantly higher body mass index (P < 0.01) than those within target range. CONCLUSIONS: Higher body mass index was associated with subprophylactic enoxaparin dosing after RC. Nearly two-thirds of patients had below target anti-factor Xa levels. This suggests that dosing could be further individualized, but given the low incidence of VTE, implications of dose-adjusted prophylaxis on VTE prevention remain unknown.

Clinicopathological characterisation of renal cell carcinoma in young adults: a contemporary update and review of literature.

AIMS: Renal cell carcinomas are relatively rare in children and young adults. While well characterised in adults, the morphological and molecular characterisation of these tumours in young patients is relatively lacking. The objective of this study was to explore the spectrum of renal cell carcinoma (RCC) subtypes in children and young adults and to determine their clinico-pathological, immunohistochemical and molecular characteristics by evaluating a large retrospective cohort of renal cell carcinoma patients age 30 years or younger. METHODS AND RESULTS: Sixty-eight cases with confirmed diagnosis of renal cell carcinoma at age 30 years or younger were identified at our institution. Clear cell carcinoma accounted for the most common subtype seen in this age group. Translocation renal cell carcinoma and rare familial syndrome subtypes such as succinate dehydrogenase deficient renal cell carcinoma and tuberous sclerosis complex-associated renal cell carcinoma were found relatively more frequently in this cohort. Despite applying the 2016 WHO classification criteria, a high proportion of the tumours in our series remained unclassified. CONCLUSIONS: Our results suggest that renal cell carcinoma in children and young adults is a relatively rare disease that shares many histological similarities to renal cell carcinoma occurring in adults and yet demonstrate some unique clinical-pathological differences. Microphthalmia-associated transcription (MiT) family translocation RCC and rare familial syndrome subtypes are relatively more frequent in the paediatric and adolescent age groups than in adults. Clear cell RCC still accounted for the most common subtype seen in this age group. MiT family translocation RCC patients presented with advanced stage disease and had poor clinical outcomes. The large and heterogeneous subgroup of unclassified renal cell carcinoma contains phenotypically distinct tumours with further potential for future subcategories in the renal cell carcinoma classification.

Clinical and morphologic review of 60 hereditary renal tumors from 30 hereditary renal cell carcinoma syndrome patients: lessons from a contemporary single institution series.

Hereditary renal cell carcinoma syndromes (HRCCS) are characterized by the presence of pathogenic germline variants that predispose patients to renal cell carcinomas as well as additional extra-renal manifestations. The importance of identifying HRCCS patients cannot be overemphasized, as patients and their families can begin surveillance for syndrome-associated manifestations once identified. The present study is a retrospective clinical and morphologic review of 60 hereditary renal tumors from 30 HRCCS patients treated at our institution with either Von Hippel-Lindau disease (VHL), Birt-Hogg-Dubé syndrome (BHD), tuberous sclerosis complex (TSC), hereditary leiomyomatosis and renal cell cancer syndrome, or succinate dehydrogenase (SDH) deficiency syndrome. Hereditary renal cell carcinoma syndromes kidney tumors often demonstrate specific morphologic features, characteristic background changes in renal parenchyma, and extra-renal manifestations, which, when recognized by the pathologist, can trigger genetic testing referral for specific familial cancer syndromes. Our study demonstrates the majority of tumors were consistent with the anticipated clinicopathologic profile of renal tumors found within HRCCS patients, although we found some unique characteristics within this cohort including a case of clear cell papillary renal cell carcinoma within a VHL patient, and a unique renal tumor with tubulopapillary features present in a patient with a germline SDHD mutation. Additionally, although the literature reports the presence of epithelioid angiomyolipoma (AML) as a common occurrence in TSC patients, our cohort of 3 patients with AMLs demonstrated only classic features. The findings we describe facilitate pathologist-based recognition of HRCCS and can prompt genetic evaluation for relevant patients.