Immune checkpoint markers and tumour mutation burden in Wilms tumour: a study of 59 cases.

Wilms tumour (WT) is the most common renal tumour in children, and studies of immune checkpoint inhibitors (ICIs) treatment and markers are limited in number. In this study we investigated the ICIs' related immune landscape by examining the expression of PD-L1, PD-1, CD8 and DNA mismatch repair (MMR) proteins by immunohistochemistry (IHC), tumour mutation burden (TMB), and correlations with histology and clinical outcome. Positive PD-L1 (SP263) expression was defined as modified combined positive score (CPS) ≥1. A total of 59 WTs (from 2000 to 2017), including eight (14.0%) with anaplasia, from 46 patients were analysed (45 primary and 14 metastatic). Thirteen WTs (13/59, 22%) were positive for PD-L1 (8 primary, 5 metastatic; CPS 1.11-3.42). Positive PD-L1 expression was associated with diffuse anaplasia (p<0.05) and significantly shorter progression-free survival (p<0.05) among WTs with favourable histology (n=39). CD8+ lymphocytes were present in all analysed WTs. A subset of CD8+ cells co-expressed PD-1, which was associated with favourable histology and treatment. MMR IHC stains identified two (2/18, 11%) WTs with isolated PMS2 loss. All six WTs analysed for TMB showed low mutation burden. We found CD8+ lymphocytes in all analysed WTs and identified a fraction of WT (17.8% of primary and 35.8% of metastatic) with positive PD-L1 CPS, suggesting potential response to ICIs in some patients.

Role of the androgen, estrogen, and progesterone receptors in adherent perinephric fat in robotic partial nephrectomy.

To determine whether androgen, estrogen, and/or progesterone signaling play a role in the pathophysiology of adherent perinephric fat (APF). We prospectively recruited patients undergoing robotic assisted partial nephrectomy during 2015-2017. The operating surgeon documented the presence or absence of APF. For those with clear cell renal cell carcinoma (ccRCC), representative sections of tumor and perinephric fat were immunohistochemically stained with monoclonal antibody to estrogen α, progesterone, and androgen receptors. Patient characteristics, operative data, and hormone receptor presence were compared between those with and without APF. Of 51 patients total, 18 (35.3%) and 33 (64.7%) patients did and did not have APF, respectively. APF was associated with history of diabetes mellitus (61.1% vs 24.2%, p = 0.009) and larger tumors (4.0 cm vs 3.0 cm, p = 0.017) but not with age, gender, BMI, Charleston comorbidity index, smoking, or preoperative estimated glomerular filtration rate. APF was not significantly associated with length of operation, positive margins, or 30-day postoperative complications but incurred higher estimated blood loss (236.5 mL vs 209.2 mL, p = 0.049). Thirty-two had ccRCC and completed hormone receptor staining. The majority of tumors and perinephric fat were negative for estrogen and progesterone while positive for androgen receptor expression. There was no difference in hormone receptor expression in either tumor or perinephric fat when classified by presence or absence of APF (p > 0.05). APF is more commonly present in patients with diabetes or larger tumors but was not associated with differential sex hormone receptor expression in ccRCC.

Enterochromaffin-like Cell Hyperplasia-Associated Gastric Neuroendocrine Tumors May Arise in the Setting of Proton Pump Inhibitor Use.

CONTEXT.­: Hypergastrinemia states such as achlorhydria from gastric mucosal atrophy or a gastrin-producing tumor in humans have been associated with the development of enterochromaffin-like (ECL) cell hyperplasia and gastric neuroendocrine tumors (GNETs). Whether drugs that can elevate serum gastrin levels, such as proton pump inhibitors (PPIs), can produce the same tissue effect is not known, and there is no concrete evidence linking the use of PPIs to GNETs outside animal models and case reports. OBJECTIVE.­: To explore the clinicopathologic association for GNETs of presumed ECL cell origin that cannot be reliably placed into any of the 3 established categories currently recognized by the World Health Organization. DESIGN.­: This is a retrospective clinicopathologic study of GNETs in the body/fundus during a period of 15 years (2005-2019). RESULTS.­: Of a total of 87 cases, 57 (65.5%) were associated with atrophic gastritis, 2 (2.3%) were associated with Zollinger-Ellison syndrome, and 28 (32.2%) were unclassified. Of the latter, 11 were consistent with true sporadic/type 3 GNETs, while 17 had background mucosal changes of parietal cell and ECL cell hyperplasia but without underlying detectable gastrinoma, and 88.2% (15 of 17) of patients from this group had documented long-term PPI use. This subtype of GNETs was more commonly multifocal and of higher grade (P = .03) than "true" sporadic GNETs. CONCLUSIONS.­: A subset of GNETs arises in the background of gastric mucosal changes suggestive of hypergastrinemia, but without underlying gastrinoma, and could be linked to long-term PPI use.

Limitations of Free Light Chain Assays caused by the Matrix Effect.

BACKGROUND: Serum free light chain (FLC) assays are used clinically to measure the concentration of κ and λ FLC in patients with suspected or diagnosed plasma cell proliferative disorders. Previous studies have demonstrated a loss of linearity in low concentration ranges of these assays. We hypothesized that this result could be caused by a matrix effect. METHODS: Recovery studies were performed for κ and λ FLC in both serum and saline using the Freelite assay (Binding Site) on a Cobas c502 system (Roche). Samples were analyzed either at the recommended dilution or undiluted. Follow-up studies were performed in varying matrices ranging from 0% to 100% saline. Retrospective patient data were analyzed to assess the impact on reported κ FLC, λ FLC, and κ/λ ratio. RESULTS: FLC in a serum matrix demonstrated underrecovery relative to samples diluted in saline for both κ and λ FLC. Of 255 patient samples with λ FLC measured undiluted (λ FLC <6.0 mg/L), an unexpected gap was observed in patient results between 2.0 and 6.0 mg/L. In addition, 23 patients measured serially with λ FLC between 2.0 and 6.0 mg/L demonstrated dramatic changes in κ/λ ratio, with no changes in κ FLC, likely because of the matrix effect. CONCLUSIONS: The κ and λ Freelite assays exhibit a matrix effect when samples are tested undiluted, which has the potential to affect the κ/λ ratio. Consequently, our laboratory has stopped reporting λ FLC <6.0 mg/L.

Unexpected High Prevalence of Lymphocytic Infiltrates in Myenteric Ganglions in Intestinal Inertia.

Intestinal inertia is a severe form of gut dysmotility that may require surgical resection. Loss of myenteric ganglion cells has been proposed as a possible etiology. Preclinical models have also suggested that virus infection-associated ganglionitis may be an alternative pathogenic factor. We determined to the extent intestinal inertia is associated with the lack of myenteric ganglion cells or ganglionitis using resection specimens from 27 intestinal inertia and 28 colon cancer patients. A hot spot approach with 5 HPFs was used for quantifying inflammatory cells. CD3, CD8, and CD20 immunohistochemistry was used to quantify T and B lymphocytes, along with subtyping the T-lymphocyte population by CD8. None of the intestinal inertia nor control cases showed the absence of myenteric ganglion cells. A total of 15 (55.6%) of the intestinal inertia cases showed inflammatory cell infiltration in the myenteric ganglion cells, compared with only 1 of 28 (3.6%) control cases (P<0.0001 by Fisher exact test). The inertia cases with inflammatory infiltrates were all associated predominantly with lymphocytes, including 3 cases (11.1%) with concurrent eosinophil infiltration, and 1 case (3.7%) with concurrent neutrophil infiltration. Furthermore, all 15 inertia cases with myenteric lymphocytic ganglionitis were associated with T lymphocytes (100%), including 1 case with a subset of concurrent B lymphocytes. The average CD3 count was 3.8 cells/HPF. CD8 immunohistochemical stain showed positive staining in 12 of the 15 cases (80%) with CD8-positive cells ranging from 1 to 8/HPF. In contrast, the only control case with lymphocytic ganglionitis showed mixed B and T lymphocytes and eosinophils. The high prevalence of T-lymphocyte infiltration in the myenteric ganglion in intestinal inertia cases suggests a possible pathogenic role.

Clinicopathologic determinants of pathologic treatment response in neoadjuvant treated rectal adenocarcinoma.

Neoadjuvant treatment (NAT) followed by total mesorectal excision is currently considered the standard of treatment for rectal adenocarcinoma. The degree of pathologic treatment response (pTR) correlates significantly with the recurrence free survival and overall survival (OS). However, it remains unclear which clinical and pathologic factors are associated with a more robust response to NAT, including showing pathologic complete response (pCR). Chemokine receptor 4 (CXCR4) overexpression has been associated with unfavorable OS in some studies. In this study, we sought to evaluate the clinicopathologic determinants of pTR in neoadjuvant treated rectal adenocarcinoma (NAT-RA). We retrospectively identified 91 patients who underwent pre-treatment diagnostic biopsy, NAT, and surgical resection at our institution. The archival slides were reviewed for pathologic features in the pre-treatment biopsies and for assessment of pTR in the resection specimens according to the current College of American Pathologist (CAP)'s guidelines. pCR was obtained in 16.5% of the cases, whereas 20.9% had near pCR, 30.8% had partial response, and 31.9% had a poor/no response. CXCR4 immunohistochemical analysis was also performed on the pre-treatment biopsies. Lower pre-treatment cT-stage (p = 0.019) and pre-treatment AJCC cTNM stage groups (p = 0.004), longer time interval between completion of NAT and resection (p = 0.022), and presence of tumor-infiltrating lymphocytes in the pre-treatment biopsies (p = 0.019) were significantly associated with a better pTR. CXCR4 nuclear expression was associated with a lower percentage of residual tumor (p = 0.036). Pre-treatment CEA levels, tumor differentiation, CAP treatment response groups and lower percentage of residual tumor were associated with a better OS.

The Angular Spectrum of the Scattering Coefficient Map Reveals Subsurface Colorectal Cancer.

Colorectal cancer diagnosis currently relies on histological detection of endoluminal neoplasia in biopsy specimens. However, clinical visual endoscopy provides no quantitative subsurface cancer information. In this ex vivo study of nine fresh human colon specimens, we report the first use of quantified subsurface scattering coefficient maps acquired by swept-source optical coherence tomography to reveal subsurface abnormities. We generate subsurface scattering coefficient maps with a novel wavelet-based-curve-fitting method that provides significantly improved accuracy. The angular spectra of scattering coefficient maps of normal tissues exhibit a spatial feature distinct from those of abnormal tissues. An angular spectrum index to quantify the differences between the normal and abnormal tissues is derived, and its strength in revealing subsurface cancer in ex vivo samples is statistically analyzed. The study demonstrates that the angular spectrum of the scattering coefficient map can effectively reveal subsurface colorectal cancer and potentially provide a fast and more accurate diagnosis.

Clinicopathological correlation of large-for-gestational age placenta in pregnancies with pregestational diabetes.

Studies have demonstrated an association between pregestational diabetes (preGDM) and a higher prevalence of large-for-gestational age placentas (LGA). However, frequency of placental pathologies and perinatal outcomes in LGA placentas is lacking. We aimed to determine differences in perinatal outcome or placental pathology between LGA placentas and appropriate-for-gestational age (AGA) placentas from pregnancies complicated by preGDM. We found LGA placentas are associated with significantly higher neonatal weight but lower fetal-to-placental weight ratio (f/p) for both T1DM and T2DM. T2DM LGA placentas possessed a significantly higher prevalence of placental insufficiency (f/p<10th percentile). Compared to LGA groups, more chronic villitis were seen in the AGA T2DM group, and more acute chorioamnionitis in the T1DM AGA group. No significant differences were seen in maternal BMI or glycemic control. In pregnancies complicated with preGDM, LGA placentas had generally lower placental efficiency than AGA placentas.

Dysplasia in Gallbladder: What Should We Do?

INTRODUCTION: On occasional cholecystectomies, pathologists encounter incidental dysplasia in the gallbladder mucosa in the sections submitted per protocol for histologic examination. If dysplasia is identified, additional sections are taken and/or the gallbladder is entirely submitted to rule out underlying adenocarcinoma. The aim of our study was to assess the incidence of subsequent identification of invasive adenocarcinoma on additional sections, after an incidentally detected dysplasia was noted on a routine cholecystectomy section. We also aimed to study the significance of the incidental detection of dysplasia and adenocarcinoma, as well as showing the association of gallbladder dysplasia to synchronous or metachronous dysplasia/neoplasia in the biliary tract. MATERIAL AND METHODS: Our study was approved by the Institutional Review Board. We retrospectively identified 41 consecutive cases of routine cholecystectomies from 1991 to 2017, which had no clinical suspicion of neoplasia, and did not have any identifiable mass lesion, but on histopathologic analysis, had neoplasia (adenocarcinoma in 4 cases, and dysplasia in 37 cases). The pathologies of all cases were reviewed, and the diagnosis and grade of dysplasia were confirmed. The clinical information was obtained from the electronic medical records. RESULTS: Of the 37 cases with dysplasia, 10 (27%) had high-grade dysplasia (HGD) and the remaining showed low-grade dysplasia (LGD). All 4 cases of adenocarcinoma had some gross abnormalities (such as porcelain gallbladder, or ruptured, thickened, and roughened walls, or a granular mucosa). In contrast, none of the 37 cases with dysplasia had any gross abnormality. In 24 (of 37) cases of dysplasia, additional sections were submitted (median 8; ranging from 2 to 29), and in 11 cases, the gallbladder was entirely submitted. None of these cases showed any additional pathologic finding on the extra sections. Interestingly, 7 cases with dysplasia (18.9%; 6 LGD and 1 HGD) were associated with a concomitant pancreatobiliary malignancy. For the remaining 30 cases, follow-up information was available in 16 cases (53.3%) with a mean follow-up of 76.5 months (ranging from 12 to 204 months). None of these showed any subsequent development of pancreatobiliary neoplasms. CONCLUSION: Incidentally detected gallbladder dysplasia in a cholecystectomy specimen, without any gross abnormality, has almost no risk of a hidden invasive carcinoma. Although cholecystectomy is sufficient treatment for gallbladder dysplasia, in our study cohort, 18.9% of cases with incidental dysplasia in gallbladder had an associated pancreatobiliary carcinoma, which supports the hypothesis of multifocal neoplastic potential in the pancreatobiliary tree (also known as field effect). Although follow-up on 16 cases shows no subsequent development of any other pancreatobiliary neoplasm, this number is probably not enough to rule out a serial imaging follow-up of patients who have reported dysplasia in their gallbladder, to assess for subsequent development of neoplasia elsewhere in the pancreaticobiliary tree.

Malignant Transformation of a Desmoplastic Ameloblastoma to Squamous Cell Carcinoma: A Case Report.

Ameloblastomas are the most common odontogenic tumors, excluding odontomas. Several morphologic variants have been described including follicular, plexiform, acanthomatous, granular cell, basaloid and desmoplastic. Desmoplastic ameloblastoma differs from other conventional ameloblastomas microscopically, clinically, and radiographically. Ameloblastic carcinoma, the malignant counterpart of ameloblastoma is characterized by cytologic features of malignancy combined within the overall histologic features of conventional ameloblastoma. Malignant transformation of ameloblastoma to squamous cell carcinoma is a controversial subject. Here we report a case of a desmoplastic ameloblastoma with malignant transformation to squamous cell carcinoma in a 49 year old African American man. The patient underwent tumor resection and radiation therapy with no evidence of disease recurrence or progression 16 months post operatively. To our knowledge malignant transformation of a desmoplastic ameloblastoma to squamous cell carcinoma has not so far been reported. This observation may lend some support to the argument that desmoplastic ameloblastoma is phenotypically and biologically distinct entity.

Feasibility of co-registered ultrasound and acoustic-resolution photoacoustic imaging of human colorectal cancer.

Colorectal cancer is the second leading cause of cancer death in the United States. Significant limitations in screening and surveillance modalities continue to hamper early detection of primary cancers or recurrences after therapy. In this study, we describe a new registered ultrasound (US) and acoustic-resolution photoacoustic microscopy (AR-PAM) system and report its initial testing in ex vivo human colorectal tissue. A total of 8 colorectal specimens were imaged, which included 2 polyps, 4 malignant colon cancers, and 2 treated colorectal cancers. In each specimen, normal tissue was also imaged for internal control. Initial data have demonstrated the feasibility of identifying colorectal cancer imaging features and the invasion depth using co-registered US and an AR-PAM system. In normal tissue, we found that our system consistently demonstrates the multi-layer structure of normal colonic tissue while differentiating layers with elevated vascularity; these findings highly correlated with histologic findings of each specimen. For malignant colorectal samples, the tissue structure is highly disorganized as seen in US, and photoacoustic imaging revealed distorted vascular distribution inside the tumor. Notably, AR-PAM of tumor beds after complete tumor destruction by radiation and chemotherapy yielded a pattern identical to benign tissue. Quantitative analysis of photoacoustic spectral slope has demonstrated more high-frequency components in malignant tissue as compared to the normal colon tissue, which may be caused by significantly increased microvessel networks. In summary, we demonstrate the successful differentiation of benign and malignant colorectal tissue with our co-registered ultrasound and photoacoustic system.

Infantile Hemangioma Presenting as Colocolic Intussusception in an Infant Case Report with Review of Pathologic Lead Points.

Infantile hemangioma (IH) is one of the most common vascular anomalies of early childhood and is usually recognized in the first few weeks to months of life as a solitary cutaneous lesion. This report documents our experience with a GLUT-1 positive IH presenting as the pathologic lead point in a colocolic intussusception in a 10-week-old infant who had no skin lesions. Literature suggests approximately 2% of all children presenting with an intussusception require surgical intervention; however, an IH as the pathologic lead point is unique.

Evans Syndrome Complicated by Intratubular Hemoglobin Cast Nephropathy.

Evans syndrome (ES) is a rare autoimmune disorder whose exact pathophysiology is unknown. It is characterized by the simultaneous or subsequent development of autoimmune hemolytic anemia (AIHA) and immune thrombocytopenia (ITP). Intravascular hemolysis, with hemoglobinemia, is known to produce acute kidney injury; however, the development of intratubular hemoglobin casts (hemoglobin cast nephropathy) in the setting of acute hemolysis is uncommon. Likewise, the association of ES and acute renal failure is equally uncommon. We present a case of a 7-year-old girl with ES who developed acute kidney injury in the setting of intravascular hemolysis and had widespread intratubular hemoglobin casts.

Rheumatoid arthritis clinical features and management strategies at an urban tertiary facility in Pakistan.

OBJECTIVE: To determine the presentation patterns, biologically vulnerable patient groups and treatment strategies of rheumatoid arthritis. METHODS: The retrospective study was conducted at the Rheumatology Clinic of Liaquat National Hospital and Medical College, Karachi, and comprised data of rheumatology patients who presented between September 2006 and September 2012. After screening all the files, rheumatoid arthritis cases were identified. Data collection was done using a questionnaire that included patient demographics, co-morbidities, clinical manifestations and drug therapy. SPSS 13 was used for statistical analysis. RESULTS: Of the 2300 files screened, 500(21.7%) related to patients of rheumatoid arthritis. The mean age at presentation of these 500 patients was 41±15 years. There were 367(73.4%) women and they presented at an earlier age compared to men (p<0.024). Erosions were present in 198(40%) patients on X-rays and 22(4.4%) had joint deformities. Seropositive rheumatoid arthritis was associated with higher erythrocyte sedimentation rate levels (p<0.014), but did not differ from seronegative rheumatoid arthritis in terms of Disease Activity Score-28 levels (p<0.21). CONCLUSIONS: The skewed gender distribution was likely an effect of rheumatoid arthritis biology rather than due to issues of healthcare accessibility. Seronegative RA is likely to present late though it is as destructive as the seropositive disease.