The Relevance of Radial Margin Status in Perihilar Cholangiocarcinoma: A State-of-the-Art Narrative Review.

BACKGROUND: Prognosis of perihilar cholangiocarcinoma (PHCC) is poor, and curative-intent resection is the most effective treatment associated with long-term survival. Surgery is technically demanding since it involves a major hepatectomy with en bloc resection of the caudate lobe and extrahepatic bile duct. Furthermore, to achieve negative margins, it may be necessary to perform concomitant vascular resection or pancreatoduodenectomy. Despite this aggressive approach, recurrence is often observed, considering 5-year recurrence-free survival below 15% and 5-year overall survival that barely exceeds 40%. SUMMARY: The literature reports that survival rates are better in patients with negative margins, and surprisingly, R0 resections range between 19% and 95%. This variability is probably due to different surgical strategies and the pathologist's expertise with specimens. In fact, a proper pathological examination of residual disease should take into consideration both the ductal and the radial margin (RM) status. Currently, detailed pathological reports are lacking, and there is a likelihood of misinterpreting residual disease status due to the missing of RM description and the utilization of various definitions for surgical margins. KEY MESSAGES: The aim of PHCC surgery is to achieve negative margins including RM. More clarity in reporting on RM is needed to define true radical resection and consistent design of oncological studies for adjuvant treatments.

Pre-Implantation Kidney Biopsies in Extended Criteria Donors: From On Call to Expert Pathologist, from Conventional Microscope to Digital Pathology.

The number of patients awaiting a kidney transplant is constantly rising but lack of organs leads kidneys from extended criteria donors (ECD) to be used to increase the donor pool. Pre-transplant biopsies are routinely evaluated through the Karpinski-Remuzzi score but consensus on its correlation with graft survival is controversial. This study aims to test a new diagnostic model relying on digital pathology to evaluate pre-transplant biopsies and to correlate it with graft outcomes. Pre-transplant biopsies from 78 ECD utilized as single kidney transplantation were scanned, converted to whole-slide images (WSIs), and reassessed by two expert nephropathologists using the Remuzzi-Karpinski score. The correlation between graft survival at 36 months median follow-up and parameters assigned by either WSI or glass slide score (GSL) by on-call pathologists was evaluated, as well as the agreement between the GSL and the WSIs score. No relation was found between the GSL assessed by on-call pathologists and graft survival (P = 0.413). Conversely, the WSI score assigned by the two nephropathologists strongly correlated with graft loss probability, as confirmed by the ROC curves analysis (DeLong test P = 0.046). Digital pathology allows to share expertise in the transplant urgent setting, ensuring higher accuracy and favoring standardization of the process. Its employment may significantly increase the predictive capability of the pre-transplant biopsy evaluation for ECD, improving the quality of allocation and patient safety.

Endoscopic ultrasound fine-needle biopsy to assess DAXX/ATRX expression and alternative lengthening of telomeres status in non-functional pancreatic neuroendocrine tumors.

BACKGROUND/OBJECTIVES: Death domain-associated protein (DAXX) and/or α-thalassemia/mental retardation X-linked (ATRX) chromatin remodeling genes mutations and alternative lengthening of telomeres (ALT) activation are associated with more aggressive behavior of non-functional pancreatic neuroendocrine tumors (NF-PanNETs). We aimed to evaluate the reliability of such markers on endoscopic-ultrasound fine-needle biopsy (EUS-FNB) specimens. METHODS: Patients who underwent EUS-FNB and subsequent surgical resection for PanNETs between January 2017 and December 2019 were retrospectively identified. Immunohistochemistry (IHC) to evaluate DAXX/ATRX expression and fluorescence in situ hybridization (FISH) for ALT status were performed. Primary outcome was the concordance rate of markers expression between EUS-FNB and surgical specimens. Secondary aims were association between markers and lesion aggressiveness, their diagnostic performance in predicting aggressiveness, and agreement of preoperative and post-surgical Ki67-based grading. RESULTS: Forty-one NF-PanNETs (mean diameter 36.1 ± 26.5 mm) were included. Twenty-four showed features of lesion aggressiveness. Concordance of expressions of DAXX, ATRX, and ALT status between EUS-FNB and surgical specimens were 95.1% (κ = 0.828; p < 0.001), 92.7% (κ = 0.626; p < 0.001), and 100% (κ = 1; p < 0.001), respectively. DAXX/ATRX loss and ALT-positivity were significantly (p < 0.05) associated with metastatic lymphnodes and lymphovascular invasion. The combination of all tumor markers (DAXX/ATRX loss + ALT-positivity + grade 2) reached an accuracy of 73.2% (95%CI 57.1-85.8) in identifying aggressive lesions. Pre- and post-operative ki-67-based grading was concordant in 80.5% of cases (k = 0.573; p < 0.001). CONCLUSION: DAXX/ATRX expression and ALT status can be accurately evaluated in a preoperative setting on EUS-FNB samples, potentially improving the identification of patients with increased risk and poorer prognosis.

The Prognostic Role of True Radical Resection in Perihilar Cholangiocarcinoma after Improved Evaluation of Radial Margin Status.

BACKGROUND: The evaluation of surgical margins in resected perihilar cholangiocarcinoma (PHCC) remains a challenging issue. Both ductal (DM) and radial margin (RM) should be considered to define true radical resections (R0). Although DM status is routinely described in pathological reports, RM status is often overlooked. Therefore, the frequency of true R0 and its impact on survival might be biased. OBJECTIVE: To improve the evaluation of RM status and investigate the impact of true R0 on survival. METHODS: From 2014 to 2020, 90 patients underwent curative surgery for PHCC at Verona University Hospital, Verona, Italy. Both DM (proximal and distal biliary margin) and RM (hepatic, periductal, and vascular margin) status were evaluated by expert hepatobiliary pathologists. Patients with lymph-node metastases or positive surgical margins (R1) were candidates for adjuvant treatment. Clinicopathological and survival data were retrieved from an institutional database. RESULTS: True R0 were 46% (41) and overall R1 were 54% (49). RM positivity resulted in being higher than DM positivity (48% versus 27%). Overall survival was better in patients with true R0 than in patients with R1 (median survival time: 53 vs. 28 months; p = 0.016). Likewise, the best recurrence-free survival was observed in R0 compared with R1 (median survival time: 32 vs. 15 months; p = 0.006). Multivariable analysis identified residual disease status as an independent prognostic factor of both OS (p = 0.009, HR = 2.68, 95% CI = 1.27-5.63) and RFS (p = 0.009, HR = 2.14, 95% CI = 1.20-3.83). CONCLUSION: Excellent survival was observed in true R0 patients. The improved evaluation of RM status is mandatory to properly stratify prognosis and select patients for adjuvant treatment.

WSI validation studies in breast and gynecological pathology.

BACKGROUND: In the last two decades, there has been marked development in virtual slide technology as well as its application in various subspecialties of pathology. In particular, there have been several studies examining the utility of whole slide imaging (WSI) in breast and gynecological pathology. The aim of this systematic review is to analyse published evidence regarding validation studies of WSI applied specifically to the female genital tract and breast pathology. METHODS: A systematic search was carried out in Pubmed and Embase databases and studies dealing with the validation of a WSI system for breast and gynaecological pathology. The topics evaluated concerned expertise of engaged pathologists, varied specimens, scanners, washout period, experience viewing WSI, and diagnostic concordance of WSI to traditional light microscopic diagnoses. RESULTS: Of 1467 publications retrieved, 23 studies were included. Most of these studies concerned breast pathology. Validation guidelines recommended by the College of American Pathologists pertaining to a dataset of at least 60 cases, washout period, and recording intra-observer variability were followed by most studies. Major challenges encountered with WSI included difficulty identifying high-grade nuclear atypia and mitotic count for borderline ovarian tumors, interpretation of squamous intraepithelial lesions in liquid-based cervical cytology, and grading breast cancer. DISCUSSION: Published data demonstrates the value of utilizing WSI in breast and gynecological pathology. Key issues reported with WSI systems were problems related to focus, resolution and the contrast and brightness of immunohistochemical staining patterns. Grading breast cancer and mitotic count remained challenging in WSI as in conventional microscopy.

Neuroendocrine tumor (NET) of the vagina in the light of WHO 2020 2-tiered grading system: clinicopathological report of the first described case.

Up to now, a vaginal well-differentiated neuroendocrine tumor (NET) has never been well described in the literature. A 2-cm vaginal nodule morphologically revealed a proliferation of mild to moderately atypical eosinophilic epithelioid cells, without tumor cell necrosis. Immunohistochemistry (IHC) showed positivity for CK (AE1/AE3), chromogranin A, and synaptophysin, focal positivity for CDX2, and negativity for PAX8 and TTF1. Metastatic origin was excluded by imaging and the morphological context with benign mucinous glands as present in the surgical resection specimen. Considering mitotic index and Mib1/Ki67 (8 mitoses/2 mm2; >20%), the case was diagnosed as vaginal NET G2 in the light of the WHO 2020 grading system for the gynecologic neuroendocrine neoplasms (NENs). Ranges of Mib1-Ki67 are not yet standardized. Currently, mitotic index and tumor cell necrosis were taken into consideration for the grading system. Gynecologic NENs still represent a diagnostic challenge. A clinico-radiologic workup and an appropriate diagnostic path ruling out the metastatic nature are mandatory to achieve the diagnosis.

Diagnostic impact of safety protocols for processing peritoneal washing specimens during the global pandemic of coronavirus disease 2019: A comparative study from 195 cytological samples.

BACKGROUND: The global pandemic of the coronavirus disease 2019 represents a major concern for health services worldwide, and has also induced major changes in cytopathology practice. AIM: We aimed to verify the diagnostic performance of cytological evaluation under a new safety protocol during the pandemic compared to the standard pre-pandemic procedure. We also aimed to assess how cytological diagnoses and sampling were impacted during the pandemic period compared to the pandemic-free period in 2019. MATERIALS AND METHODS: Cytological samples of peritoneal washings taken during the first 10 months of the pandemic emergency in Italy (March 11, 2020 to January 11, 2021) were compared to samples from the preceding 10-month time frame (May 11, 2019 to March 10, 2020). RESULTS: One hundred ninety-five specimens were analysed in the present study. We observed no noticeable differences in cytological diagnoses during the pandemic period compared to the pre-pandemic period. The case numbers by diagnostic category for the pre-pandemic vs pandemic periods, respectively, were as follows: non-diagnostic, 0 vs 0 cases; negative for malignancy, 86 vs 52 cases; atypia of uncertain significance, 7 vs 1 cases; suspicious for malignancy, 0 vs 2 cases; malignant, 42 vs 4 cases. CONCLUSION: While a consistent reduction in the number of cytological examinations has been observed during the COVID-19 period, our institutional safety protocol for processing cytological samples did not affect the diagnostic reliability of peritoneal washing cytology.

Comparison between EUS-guided fine-needle aspiration cytology and EUS-guided fine-needle biopsy histology for the evaluation of pancreatic neuroendocrine tumors.

BACKGROUND/OBJECTIVES: Studies comparing EUS-guided fine-needle aspiration (EUS-FNA) with EUS-guided fine-needle biopsy (EUS-FNB) for the evaluation of pancreatic neuroendocrine tumors (pNETs) are lacking. We aimed at comparing EUS-FNA with EUS-FNB in terms of Ki-67 proliferative index (PI) estimation capability, cellularity of the samples, and reliability of Ki-67 PI/tumor grading compared with surgical specimens. METHODS: Patients diagnosed with pNETs on EUS and/or surgical specimens were retrospectively identified. Specimens were re-evaluated to assess Ki-67 PI feasibility, sample cellularity by manual counting, and determination of Ki-67 PI value. Outcomes in the EUS-FNA and EUS-FNB groups were compared. Kendall rank test was used for Ki-67 PI correlation between EUS and surgical specimens. Subgroup analysis including small (≤20 mm), non-functioning pNETs was performed. RESULTS: Three-hundred samples from 292 lesions were evaluated: 69 EUS-FNA cytology and 231 EUS-FNB histology. Ki-67 PI feasibility was similar for EUS-FNA and EUS-FNB (91.3% vs. 95.7%, p = 0.15), while EUS-FNB performed significantly better in the subgroup of 179 small pNETs (88.2% vs. 96.1%, p = 0.04). Rate of poor cellulated (<500 cells) specimens was equal between EUS-FNA and EUS-FNB. A significant correlation for Ki-67 PI values between EUS and 92 correspondent surgical specimens was found in both groups, but it was stronger with EUS-FNB (tau = 0.626, p < 0.0001 vs. tau = 0.452, p = 0.031). Correct grading estimation was comparable between the two groups (p = 0.482). CONCLUSION: Our study showed stronger correlation for Ki-67 values between EUS-FNB and surgical specimens, and that EUS-FNB outperformed EUS-FNA in the evaluation of small pNETs. EUS-FNB should become standard of care for grading assessment of suspected pNETs.