Oldies, but goldies-preserved morphology and stability of antigenic determinants in decades-old cryosections of human m. vastus lateralis.

Fibre typing by immunohistochemistry on cryosections from human skeletal muscle biopsies is an essential tool in the diagnosis and research of muscular diseases, ageing, and responses to exercise training and disuse. Preserving a good quality in these frozen specimens can be challenging especially if they are stored for longer periods before histological processing, which is often the case in studies with a large number of test subjects and/or repeated sampling separated by multiple years. We demonstrate in this article that both, the morphology and reactivity of epitopes to myosin heavy chain isoforms and dystrophin are well preserved in up to 18-year-stored unfixed and unstained cryosections of human m. vastus lateralis (n = 241). Any variation in staining intensity between samples was unrelated to the age of the biopsy donor or the storage period of the unstained cryosections, and in all cases, the obtained images were appropriate for image analysis, such as the determination of the fibre type composition and the fibre cross-sectional area, and quantitative analysis of muscle capillarisation.

Centralized prostatectomy with intraoperative NeuroSAFE margin assessment improves surgical margin control.

AIMS: To investigate the surgical margin status in patients with prostate cancer who underwent robot-assisted radical prostatectomy (RARP) with intraoperative neurovascular structure-adjacent frozen-section analysis (NeuroSAFE) and evaluate differences compared to patients who underwent radical prostatectomy without NeuroSAFE. PATIENTS AND METHODS: Between September 2018 and January 2021, 962 patients underwent centralized RARP with NeuroSAFE. A secondary resection was performed in case of a positive surgical margin (PSM) on intraoperative frozen section (IFS) analysis to convert a PSM into a negative surgical margin (NSM). A retrospective cohort consisted of 835 patients who had undergone radical prostatectomy in a tertiary centre without NeuroSAFE between January 2000 and December 2017. We performed multivariable logistic regression to evaluate differences in risk of PSM between cohorts after controlling for clinicopathological variables. RESULTS: Patients operated with NeuroSAFE in the centralized clinic had 29% PSM at a definitive pathological RP examination. The median cumulative length of definitive PSM was 1.1 mm (interquartile range: 0.4-3.8). Among 275 men with PSM, 136 (49%) had a cumulative length ≤1 mm and 198 (72%) ≤3 mm. After controlling for PSA, Grade group, cribriform pattern, pT-stage, and pN-stage, patients treated in the centralized clinic with NeuroSAFE had significantly lower odds on PSM (odds ratio [OR]: 0.70, 95% confidence interval [CI]: 0.56-0.88; P = 0.002), PSM length >1 mm (OR: 0.14, 95% CI: 0.09-0.22; P < 0.001), and >3 mm (OR: 0.21, 95% CI: 0.14-0.30; P < 0.001). CONCLUSION: This study provides a detailed overview of surgical margin status in a centralized RP NeuroSAFE cohort. Centralization with NeuroSAFE was associated with lower PSM rates and significantly shorter PSM cumulative lengths, indicating improved control of surgical margin status.

Immunofluorescence staining of chloroplast proteins with frozen sections of plant tissues.

KEY MESSAGE: Immunofluorescence staining with frozen sections of plant tissues and a nest tube is convenient and effective, and broadens the applicability of immunofluorescence staining. Immunofluorescence staining is an indispensable and extensively employed technique for determining the subcellular localization of chloroplast division proteins. At present, it is difficult to effectively observe the localization of target proteins in leaves that are hard, or very thin, or have epidermal hair or glands with the current immunofluorescence staining methods. Moreover, signals of target proteins were predominantly detected in mesophyll cells, not the cells of other types. Thus, the method of immunofluorescence staining was further explored for improvement in this study. The plant tissue was embedded with 50% PEG4000 at -60℃, which was then cut into sections by a cryomacrotome. The sections were immediately immersed in fixation solution. Then, the sample was transferred into a special nested plastic tube, which facilitated the fixation and immunofluorescence staining procedures. The use of frozen sections in this method enabled a short processing time and reduced material requirements. By optimizing the thickness of the sections, a large proportion of the cells could be well stained. With this method, we observed the localization of a chloroplast division protein FtsZ1 in the wild-type Arabidopsis and various chloroplast division mutants. Meanwhile, the localization of FtsZ1 was also observed not only in mesophyll cells, but also in guard cells and epidermal cells in a lot of other plant species, including many species with hard leaf tissues. This method is not only easy to use, but also expands the scope of applicability for immunofluorescence staining.

Incidental findings during donor liver assessment: Single center experience.

Intraoperative consultation of donor liver is an important part of transplant evaluation and determination of liver eligibility. In this study, we describe incidental pathologic findings discovered during the pretransplant evaluation of liver donors in our Institution from 1/2010 to 12/2022. During this 13-year period 369 intraoperative consultations from 262 liver donors were performed. Of those cases, incidental findings were identified in 22 cases (5.9 %) from 19 donors (7.3 %); two donors had more than one lesion. The median age of this subset of patients was 53 years (range: 18-70) and females predominated (63 %). Sixteen of the donors had abnormal findings in the liver: 6 bile duct hamartoma (BDH), 5 hyalinized nodule with Histoplasma capsulatum, 5 focal nodular hyperplasia (FNH), 2 bile duct adenomas (BDA), 1 biliary cyst and 1 hemangioma. One donor had both FNH and a BDH. One BDH and 1 BDA case was misdiagnosed as malignancy during the frozen section evaluation. Three donors had extrahepatic pathologies: a pancreatic tail schwannoma, a low-grade appendiceal mucinous neoplasm, and a lymph node with metastatic endometrial endometrioid adenocarcinoma. Of the 19 livers, the final organ disposition was available for 9: 6 were transplanted (67 %) and 3 were discarded (33 %). Two of the 3 discarded organs were misdiagnosed BDH and BDA cases, and one was incorrectly reported as having 90 % microvesicular steatosis during the frozen assessment. We present the clinicopathologic characteristics of liver donors with incidental findings during the pre-transplant evaluation which could lead to unwarranted graft dismissal if misdiagnosed. Additionally, incidental fungal infections can have implications for immunosuppressive therapy and the decision to use or reject the graft.

Intraoperative frozen section analysis of margin status as a quality indicator in gastric cancer surgery.

INTRODUCTION: Positive pathologic margins following gastric cancer (GC) resection carries a poor prognosis. We evaluated intraoperative frozen section (IFS) analysis of resection margins (RMs) as a quality indicator in GC surgery. METHODS: Patients referred to a provincial cancer agency with surgically resected non-metastatic GC between 2004 and 2012 were included. Associations between IFS analysis, other baseline characteristics, RMs, and overall survival (OS) were assessed using logistic regression, Kaplan-Meier analyses, and Cox proportional hazards modeling. RESULTS: Among 377 patients, median age was 67 years, 68% were male, and 16% had +RMs. Thirty-four percent of patients underwent IFS analysis, which protected against +RMs (odds ratio [OR]: 0.34, 95% confidence interval [CI]: 0.16-0.73, p = 0.006) and improved OS (hazards ratio [HR]: 0.72, 95% CI: 0.54-0.98, p = 0.037). OS following re-resection of IFS positive patients was similar to IFS negative patients (69 vs. 54 months, p = 0.317). Stage III disease (OR: 12.8, 95% CI: 3.00-55.0, p = 0.001) and gastroesophageal junction tumors (OR: 2.25, 95% CI: 1.05-4.78, p = 0.036) predicted +RMs. Stage III disease led to worse OS (HR: 2.89, 95% CI: 1.92-4.34, p < 0.001) while intestinal histology improved OS (HR: 0.67, 95% CI: 0.50-0.90, p = 0.007). CONCLUSIONS: IFS analysis reduce +RMs and improve OS and should be incorporated in curative intent GC surgery for patients with locally advanced GC.

Utility and diagnostic accuracy of intraoperative frozen sections in hepato-pancreato-biliary surgical pathology.

BACKGROUND AND PURPOSE: Hepato-pancreato-biliary (HPB) surgeries are one of the most challenging and complex procedures. Intraoperative frozen section (IFS) diagnosis plays a pivotal role in management decisions. Comprehensive large cohort studies evaluating utility of IFS in HPB malignancies are lacking. This study aimed to evaluate the accuracy of frozen section analysis and to analyse discrepancies and impact of IFS on the surgical decisions. PATIENTS AND METHODS: This was a retrospective study of IFS received for the HPB specimens between years 2009 and 2021. The results were compared to the permanent sections to evaluate diagnostic accuracy, sensitivity and specificity. Indications, disagreements and impact on the surgical management were analysed. RESULTS: A total of 1008 specimens were evaluated: bile duct margin (279; 27.7%), gallbladder (203; 20.1%), liver lesions (125 cases; 12.4%), lymph nodes (147; 14.6%), pancreatic margin (120; 11.9%) and deposits (134; 13.3%). IFS were diagnosed as negative for malignancy (805; 79.9%), positive for dysplasia (8; 0.8%), suspicious for malignancy (6; 0.6%) and positive for malignancy (189; 18.8%). The overall diagnostic accuracy was 98.4%, and the discordant rate was 1.6%. The sensitivity, specificity, positive predictive value and negative predictive value were 94.7%, 99.4%, 97.5% and 98.6% respectively. The most important reason of discordant results was technical, followed by interpretational and sampling errors. CONCLUSION: The study demonstrates high diagnostic accuracy (98.4%) of IFS in a large dataset of HPB specimens. This comprehensive analysis apprises of the indications, errors and the impact of IFS diagnosis on subsequent HPB surgical management.

Frozen Sections in Decision-Making Regarding the Axillary Procedures in Breast Conserving Surgery for Intraductal Carcinoma at Preoperative Diagnosis.

BACKGROUND: Axillary evaluation is unnecessary for pure ductal carcinoma in situ (DCIS); however, it is performed because of the risk of upstaging to invasive cancer. We assessed the role of intraoperative frozen section (IOF) biopsy in reducing invasive cancer upstaging and axillary evaluation in preoperative DCIS patients. METHODS: We reviewed patients with preoperative DCIS who underwent breast-conserving surgery (BCS) with IOF biopsy. Positive IOF biopsy findings were defined as the presence of invasive or micro-invasive cancer. The IOF biopsy and permanent pathology findings were compared. RESULTS: Seventy-eight patients underwent BCS with IOF biopsy. Six patients showed positive IOF biopsy findings; five of these patients showed concordant permanent pathology findings. Sentinel lymph node biopsy (SLNB) was positive in one patient. Thirteen patients with invasive breast cancer were missed by IOF biopsy; they underwent SLNB during the second surgery. None of them had metastatic lymph nodes. The sensitivity and specificity of IOF biopsy were 27.7% and 98.3%, respectively, with 82.1% accuracy. None of the other factors showed statistically significant relationships with the permanent pathology findings, except for the IOF biopsy findings. CONCLUSION: IOF evaluation can aid in detecting the invasiveness of tumors in patients with preoperative DCIS.

Neural Network Based Classification of Breast Cancer Histopathological Image from Intraoperative Rapid Frozen Sections.

Breast cancer is the leading cause of cancer-related mortality in women worldwide. Despite the rapid developments in diagnostic techniques and medical sciences, pathologic diagnosis is still recognized as the gold standard for disease diagnose. Pathologic diagnosis is a time-consuming task performed for pathologists, needing profound professional knowledge and long-term accumulated diagnostic experience. Therefore, the development of automatic and precise histopathological image classification is essential for medical diagnosis. In this study, an improved VGG network was used to classify the breast cancer histopathological image from intraoperative rapid frozen sections. We adopt a transformed loss function by adding a penalty to cross-entropy in our training stage, which improved the accuracy on test data by 4.39%. Laplacian-4 was used for the enhancement of images, which contributes to the improvement of the accuracy. The accuracy of the proposed model on training data and test data reached 88.70% and 82.27%, respectively, which outperforms the original model by 9.39% of accuracy in test data. The process time was less than 0.25 s per image on average. Meanwhile, the heat maps of predictions were given to show the evidential regions in histopathological images, which could drive improvements in the accuracy, speed, and clinical value of pathological diagnoses. In addition to helping with the actual diagnosis, this technology may be a benefit to pathologists, surgeons, and patients. It might prove to be a helpful tool for pathologists in the future.

Converted-hepatopancreatoduodenectomy for an intraoperative positive ductal margin after pancreatoduodenectomy in distal cholangiocarcinoma.

PURPOSE: Pancreatoduodenectomy (PD) is the standard treatment for distal cholangiocarcinoma, and a negative ductal margin (DM0) is indispensable for the long-term survival. When intraoperative frozen sections of ductal margin after PD are positive, converted-hepatopancreatoduodenectomy (C-HPD) is the final option available to gain an additional ductal margin. However, the efficacy of C-HPD remains unclear. METHODS: Patients who underwent PD or C-HPD for distal cholangiocarcinoma between 2002 and 2019 were analyzed. The type of hepatectomy in C-HPD was restricted to left hepatectomy to prevent posthepatectomy liver failure. RESULTS: Of 203 patients who underwent PD for distal cholangiocarcinoma, 49 patients exhibited intraoperative positive ductal margin (DM1) after PD. Eleven patients underwent C-HPD for intraoperative DM1 after PD, in which intraoperative DM1 with invasive carcinoma (DM1inv) was observed in 3 patients, and intraoperative DM1 with carcinoma in situ (DM1cis) was observed in 8 patients. The median additional ductal margin yielded by C-HPD was 9 mm (interquartile range 7-13 mm). C-HPD eradicated intraoperative DM1inv in 3 patients, with 2 patients showing DM0 and 1 patient showing DM1cis. Regarding 8 patients who underwent C-HPD for intraoperative DM1cis, 4 patients had DM0, but the others had DM1cis. C-HPD was associated with a high complication rate, but no mortality was observed. The median survival time of patients who underwent C-HPD was 48.8 months. CONCLUSION: C-HPD was able to safely eradicate intraoperative DM1inv after PD. However, the length of the resected bile duct according to C-HPD may not be sufficient to remove intraoperative DM1cis after PD.

IS CONFIRMATION OF PARATHYROID TISSUE BY FROZEN SECTION SUPERIOR TO LOCALIZATION OF SOLITARY PARATHYROID ADENOMA USING INTRAOPERATIVE GAMMA PROBE SURVEY? A RETROSPECTIVE COHORT STUDY.

Context: In the surgical treatment of primary hyperparathyroidism, intraoperative localization of the diseased glands is an essential issue. We aimed to evaluate the impact of the intraoperative frozen section during radio-guided focused parathyroidectomy and compare its efficiency with intraoperative gamma probe survey and measurement of intraoperative quick parathyroid hormone. Methods: All consecutive patients underwent radio-guided focused parathyroidectomy for primary hyperparathyroidism due to solitary parathyroid adenoma. The outcomes of parathyroidectomy were evaluated by serum levels of calcium and parathyroid hormone. The primary outcome was the surgical cure diagnosed by normal serum calcium levels in the sixth postoperative month. Results: A total of 55 patients with a mean age of 54.3±12.2 years were evaluated. The diagnostic accuracy of the preoperative localization tests was calculated as 92.7%. The intraoperative gamma probe survey impacted the operative plans of four patients (7.3%) by localizing the diseased gland in other positions. The accuracy of intraoperative quick parathyroid hormone and frozen section analysis was 100% for both. In all patients, serum calcium and PTH levels dropped to normal in the sixth postoperative month. There were no cases of the persistent or recurrent disease during the follow-up period. Conclusion: The results of the intraoperative gamma probe survey, intraoperative quick parathyroid hormone, and frozen section were concordant with the final pathology in all cases. In four patients (7.3%), intraoperative gamma probe survey impacted the operative plans. The intraoperative gamma probe survey may be used as the sole intraoperative method to locate the correct position of the solitary parathyroid adenoma.

Could concurrent biopsy and microwave ablation be reliable? Concordance between frozen section examination and final pathology in CT-guided biopsy of lung cancer.

PURPOSE: Microwave ablation combined with concurrent biopsy has been used for lung cancer. Frozen section (FS) diagnosis is an important supplement for the final pathology (FP). Thus, a retrospective study was conducted to evaluate the concordance between FS examination and FP in the computed tomography (CT)-guided biopsy of lung cancer. MATERIALS AND METHODS: Patients who underwent percutaneous transthoracic needle lung biopsies and were diagnosed using both intraoperative FS examination and FP were retrospectively enrolled. Concordance between FS findings and FP in the diagnosis of malignant lung cancer and the definitive histology types were recorded. RESULTS: Overall, 163 patients were enrolled. The concordance rate in the diagnosis of malignant tumors was 96.3%. The definitive histology types were concordant between FS examinations and FP in 112 patients (68.7%). Lung cancers undefined with FS but diagnosed as adenocarcinoma with FP were the most common type, observed in 18 patients. The concordance in the histology type was lower for those requiring immunohistochemistry for FP diagnoses (47.3 vs. 79.6%, p < 0.000). Concordance rates differed for the different histology types diagnosed using FP (adenocarcinoma vs. squamous cell carcinoma vs. small-cell lung cancer vs. others, 76.6 vs. 56.2 vs. 69.2 vs. 0.0%, p < 0.000). CONCLUSIONS: FS was inferior to FP in the diagnosis of definitive histology types, but had a high concordance with FP in the diagnosis of malignant lung cancer.

How accurate is frozen section pathology compared to permanent pathology in detecting involved margins and lymph nodes in breast cancer?

BACKGROUND: Frozen section (FS) pathology has multiple limitations, and different institutions report variable experiences with the use of FS for diagnosis of tumor involvement. We aimed to compare the FS accuracy with that of permanent pathology (gold standard) regarding marginal involvement and lymph node status using data from the largest breast cancer registry in Iran. METHODS: In this retrospective study, women who had both FS and permanent pathology reports were included. The two pathology reports were cross compared with regard to the involvement of tumor margins and sentinel lymph nodes. RESULTS: Overall, 2786 patients entered the study. Mean age of patients was 48.96±11.44 years. A total of 1742 margins were analyzed. Accordingly, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of FS pathology for detection of involvement of involved margins were 78.49%, 97.63%, 65.1%, and 98.7%, respectively. The accuracy and area under the curve (AUC) for FS pathology were 96.61% and 0.73 (95% CI: 0.64-0.831), respectively. A total of 1702 sentinel lymph node biopsies were assessed. Sensitivity, specificity, PPV, and NPV, of FS pathology for detection of lymph node involvement, were 87.1%, 98%, 95.5%, and 93.3%, respectively. Accuracy and AUC of FS for diagnosis of involved lymph nodes were 94.1% and 0.926 (95% CI: 0.909-0.942), respectively. CONCLUSION: Frozen pathology is a suitable method for identifying involved sentinel lymph nodes in patients with breast cancer, but this method has a less than optimum efficacy for detecting and confirming marginal involvement.

Preoperative CT-based radiomics combined with intraoperative frozen section is predictive of invasive adenocarcinoma in pulmonary nodules: a multicenter study.

OBJECTIVES: Develop a CT-based radiomics model and combine it with frozen section (FS) and clinical data to distinguish invasive adenocarcinomas (IA) from preinvasive lesions/minimally invasive adenocarcinomas (PM). METHODS: This multicenter study cohort of 623 lung adenocarcinomas was split into training (n = 331), testing (n = 143), and external validation dataset (n = 149). Random forest models were built using selected radiomics features, results from FS, lesion volume, clinical and semantic features, and combinations thereof. The area under the receiver operator characteristic curves (AUC) was used to evaluate model performances. The diagnosis accuracy, calibration, and decision curves of models were tested. RESULTS: The radiomics-based model shows good predictive performance and diagnostic accuracy for distinguishing IA from PM, with AUCs of 0.89, 0.89, and 0.88, in the training, testing, and validation datasets, respectively, and with corresponding accuracies of 0.82, 0.79, and 0.85. Adding lesion volume and FS significantly increases the performance of the model with AUCs of 0.96, 0.97, and 0.96, and with accuracies of 0.91, 0.94, and 0.93 in the three datasets. There is no significant difference in AUC between the FS model enriched with radiomics and volume against an FS model enriched with volume alone, while the former has higher accuracy. The model combining all available information shows minor non-significant improvements in AUC and accuracy compared with an FS model enriched with radiomics and volume. CONCLUSIONS: Radiomics signatures are potential biomarkers for the risk of IA, especially in combination with FS, and could help guide surgical strategy for pulmonary nodules patients. KEY POINTS: • A CT-based radiomics model may be a valuable tool for preoperative prediction of invasive adenocarcinoma for patients with pulmonary nodules. • Radiomics combined with frozen sections could help in guiding surgery strategy for patients with pulmonary nodules.

Direct intraoperative assessment of total mesorectal excision specimens by expert pathologists in patients with very low rectal cancer prevents unnecessary abdominoperineal resections.

PURPOSE: In patients with low rectal cancer, the intraoperative assessment of sufficient distal resection margins can be challenging. The assessment determines whether reconstruction can be performed or whether permanent colostomy is required. The goal of the present study was to evaluate intraoperative assessment of the total mesorectal excision (TME) specimen during an interruption of the operation. METHODS: The intraoperative strategy of eight patients with low rectal cancer was evaluated. In all cases, intraoperative pathological assessment of the TME specimen by an expert pathologist together with the surgeon was performed. Assessment of the distance of the tumor to the resection margin was measured macroscopically as well as microscopically. RESULTS: All patients underwent neoadjuvant chemoradiation. The tumor was located at an average 4.8 ± 1.4 cm from the anal verge. In all cases, preoperative MRI revealed mrT3 tumors. The intraoperative assessment showed a median distal resection margin of 10 mm (2-15 mm). In six patients, sufficient margins allowed for reconstruction while in two patients APR was needed. In three patients (37.5%), the pathological assessment changed the operative strategy: In one patient APR could be avoided while two patients required APR instead of the anticipated TME. CONCLUSION: The intraoperative assessment of the TME specimen by an expert pathologist together with the surgeon is a valuable tool to avoid unnecessary APR or R1 resections. We therefore suggest routine intraoperative pathological assessment in all operations for borderline low rectal cancers.

Diagnostic performance of intraoperative assessment in grade 2 endometrioid endometrial carcinoma.

BACKGROUND: Endometrial carcinoma is the most common gynecologic malignancy in developed countries. Grade 2 carcinoma is associated with pelvic lymph-node metastasis, depending on selected risk factors. Intraoperative assessment (IOA) can identify patients at risk for lymph node metastasis who should undergo staging surgery. Our objective was to establish the diagnostic precision of IOA in determining the need for surgical staging in grade 2 endometrioid endometrial carcinoma. METHODS: Two hundred twenty-two patients underwent IOA. Results were compared to the final pathology report. The accuracy of the IOA parameters was calculated. Variables were evaluated in patients with positive versus negative IOA. Overall and disease-free survivals were calculated according to IOA, lymphadenectomy, and nodal metastasis. RESULTS: IOA was positive in 80 patients. It showed an accuracy of 76.13% when compared with the postoperative assessment. The best individual parameter was myometrial invasion. Nodal metastasis was observed in 16 patients in the positive IOA group and 7 patients in the negative group. Patients with lymph node metastasis had a 5-year overall survival rate of 80.9%, whereas patients without metastasis had a 5-year overall survival rate of 97.9%. CONCLUSIONS: IOA is an adequate tool to identify high-risk patients in grade 2 endometrial carcinoma. Myometrial invasion is the individual parameter that yields the highest diagnostic precision.

The Impact of Omission of Intraoperative Frozen Section Prior to Orthotopic Neobladder Reconstruction.

PURPOSE: Current guidelines recommend confirming a negative urethral margin prior to orthotopic neobladder reconstruction. We investigated our rate of urethral positive margins and recurrence in the absence of intraoperative frozen section. MATERIALS AND METHODS: We retrospectively reviewed clinical and pathological data on 357 patients who underwent radical cystectomy and orthotopic urinary diversion without intraoperative frozen section. At a median followup of 27 months the rates of positive urethral margins and urethral recurrence were tabulated. Differences in overall and recurrence-free survival in patients with a positive urethral margin were analyzed by Cox regression to generate the HR with the 95% CI. RESULTS: We identified 6 urethral recurrences (1.6%) during followup. The urethral recurrence rate was not higher in patients with a positive urethral margin (p=0.22). In the 15 patients with positive urethral margins overall survival was unchanged (HR 0.98, 95% CI 0.24-4.04). When accounting for lymph node staging, recurrence-free survival was not significantly worse in patients with positive urethral margins (HR 2.33, 95% CI 0.95-5.73). CONCLUSIONS: Omitting intraoperative frozen section prior to orthotopic neobladder reconstruction appears safe with a rate of urethral recurrence similar to that in historical series. It may allow for increased performance of orthotopic urinary diversions.

The impact on oncological outcomes after radical prostatectomy for prostate cancer of converting soft tissue margins at the apex and bladder neck from tumour-positive to -negative.

OBJECTIVES: To assess the impact of conversion from histologically positive to negative soft tissue margins at the apex and bladder neck on biochemical recurrence-free survival (BCRFS) and distant metastasis-free survival (DMFS) after radical prostatectomy (RP) for prostate cancer. MATERIALS AND METHODS: The records of 2 013 patients who underwent RP and intra-operative frozen section (IFS) analysis between July 2007 and June 2016 were reviewed. IFS analysis of the urethra and bladder neck was performed, and if malignant or atypical cells remained, further resection with the aim of achieving histological negativity was carried out. Patients were divided into three groups according to the findings: those with a negative surgical margin (NSM), a positive surgical margin converted to negative (NCSM) and a persistent positive surgical margin (PSM). RESULTS: Among the 2 013 patients, rates of NSMs, NCSMs and PSMs were 75.1%, 4.9%, and 20.0%, respectively. The 5-year BCRFS rates of patients with NSMs, NCSMs and PSMs were 89.6%, 85.1% and 57.1%, respectively (P < 0.001). In both pathological (p)T2 and pT3 cancers, the 5-year BCRFS rate for patients with NCSMs was similar to that for patients with NSMs, and higher than for patients with PSMs. The 7-year DMFS rates of patients with NSMs, NCSMs and PSMs were 97.8%, 99.1% and 89.4%, respectively (P < 0.001). Among patients with pT3 cancers, the 7-year DMFS rate was significantly higher in the NCSM group than in the PSM group (98.0% vs 86.7%; P = 0.023), but not among those with pT2 cancers (100% vs 96.9%; P = 0.616). The 5-year BCRFS rate for the NCSM group was not significantly different from that of the NSM group among the patients with low- (96.3% vs 95.8%) and intermediate-risk disease (91.1% vs 82.8%), but was lower than that of the NSM group among patients in the high-risk group (73.2% vs 54.7%). CONCLUSIONS: Conversion of the soft tissue margin at the prostate apex and bladder neck from histologically positive to negative improved the BCRFS and DMFS after RP for prostate cancer; however, the benefit of conversion was not apparent in patients in the high-risk group.

[Tumor-suspected focal lesion on the renal hilus]. / Tumorverdächtiger Herdbefund am Nierenhilus.

Mucosal structures of a non-neoplastic organ can result in a pitfall diagnosis of adenocarcinoma in the case of a wrong correlation with other organs, in this case caused by an adherent gallbladder to the hilar structures of the right kidney. Clinical and radiological data are absolutely crucial for a correct classification.

Pulmonary sclerosing pneumocytoma remains a diagnostic challenge using frozen sections: a clinicopathological analysis of 59 cases.

AIMS: Using intraoperative frozen sections to diagnose pulmonary sclerosing pneumocytoma is always challenging. However, an accurate diagnosis is needed to guide surgical management and prevent unnecessary treatment. The aim of this study was to investigate the most frequently misdiagnosed histological patterns and evaluate the potential diagnostic pitfalls of using frozen sections. METHODS AND RESULTS: We reviewed retrospectively 59 cases of sclerosing pneumocytoma that underwent an intraoperative frozen section examination. All original frozen section slides and permanent section slides were reviewed. The rate of accurate diagnosis using frozen sections was 44.1%, the deferral rate was 15.3% and 10 cases (16.9%) were misdiagnosed as malignancy. A solid-predominant pattern is misdiagnosed more frequently than other growth patterns. We also summarised the five major diagnostic pitfalls, including hypercellularity, glandular spaces, desmoplasia-like sclerosis, cellular atypia and coagulative necrosis. CONCLUSIONS: In addition to evaluating the tumour circumscription and identifying the various growth patterns, we propose that the key to avoiding a misdiagnosis is to recognise the dual-cell populations in a tumour, i.e. cuboidal surface cells and stromal round cells.

Diagnostic Utility of Histological Analysis for Detecting Ongoing Infection During Two-Stage Revision Arthroplasty in Patients With Inflammatory Arthritis.

BACKGROUND: Surgeons often rely on intra-operative histology (frozen sections [FS]) to determine the next step in surgical management during the second stage (re-implantation surgery) of 2-stage revision arthroplasty. The purpose of the study is to assess the accuracy of permanent sections (PS) and FS in the diagnosis of persistent infection during re-implantation in patients with an inflammatory arthritis. METHODS: From 2001 to 2016, 47 planned second-stage revision total hip arthroplasty and total knee arthroplasty in patients with inflammatory arthritis were identified. Revisions were classified as having persistent infection if they were Musculoskeletal Infection Society positive at the time of second stage. PS or FS was considered to be positive for infection when at least one of the specimens demonstrated an acute inflammation. Receiver operating characteristic analysis was performed to obtain the diagnostic parameters. RESULTS: There were 9 (19%) persistent infections. Both PS and FS had very high specificity (PS = FS = 94.7%). Sensitivity of PS was higher than FS, although not statistically significant (PS = 88.9%, FS = 55.6%, P = .083). Overall, PS had a better diagnostic utility than FS (area under the curve: PS vs FS = 0.92 vs 0.75, P = .045). Four specimens had discrepancies between PS and FS histology. In all 4 instances, the specimens were read as positive (infected) by PS, but negative by FS. CONCLUSION: Histological analysis is recommended at the time of re-implantation surgery even in patients with inflammatory arthritis. PS had a better diagnostic utility than FS suggesting that areas of acute inflammation may be scattered and may not always be captured in the specimens taken for FS.