Paul Staats

A silk-based encapsulation platform for pancreatic islet transplantation improves islet function in vivo.

The success of pancreatic islet (PI) transplantation is challenged by PI functional damage during the peritransplantation period. A silk‐based encapsulation platform including mesenchymal stromal cells (MSCs) was evaluated for islet cell delivery in vivo. Islet equivalents (IEQs) were transplanted into the epididymal fat pads of mice with streptozotocin‐induced diabetes. Three PI combinations were tested: (A) co‐encapsulated in silk with MSCs; (b) encapsulated in silk alone; or (c) pelleted. Blood glucose levels were monitored and intraperitoneal glucose tolerance test (IPGTT) was performed upon return to euglycaemia. Grafts were removed for histology and cytokine content analysis. Mice with PI grafts in silk showed a prompt return to euglycaemia. IPGTT was significantly improved with PI in silk with MSCs, compared to PI in silk alone or pelleted. Both Th1 and Th2 cytokines were increased in PI grafts in silk, but Th1 cytokines were decreased significantly with PI and MSC co‐encapsulation. Histological analysis showed osteogenesis and chondrogenesis in the silk grafts containing MSCs. Future studies will evaluate MSC stability and function in vivo and improve silk biocompatibility for applications in islet transplantation. Copyright

Diffuse mesothelioma of the peritoneum: correlation between histological and clinical parameters and survival in 73 patients

Summary There are few studies addressing survival of diffuse peritoneal mesotheliomas (DPM). In this study, survival data were obtained retrospectively from 73 patients treated with intended cytoreductive surgery for DPM, with a mean follow-up of 42 months. Mesotheliomas were classified as well differentiated papillary (WDPM, n = 2), multicystic (MCM, n = 4), and epithelioid mesotheliomas were subclassified as tubulopapillary (TPM, n = 27), solid/deciduoid (S/DM, n = 34), and or biphasic mesothelioma (BPM, n = 6). Invasion was characterised as absent (grade 0), into stroma (grade 1), into fat (grade 2), and into adjacent structures (grade 3). Peritoneal cancer index (PCI) and completeness of cytoreduction (CCR) were assessed surgically. There were no deaths in the WDPM, MCM, and epithelioid DPM with ⩽ grade 1 invasion. There was a stepwise decrease in overall survival from invasive TPM, S/DM, and BPM (p < 0.0001). By univariate analysis, advanced age (p = 0.01), incomplete CCR (p < 0.001), PCI (p = 0.004), mitotic count (p < 0.001), nuclear grade (p < 0.0001), stromal inflammation (p = 0.013), depth of invasion (p < 0.0001), necrosis (p = 0.002), and sarcomatoid growth (p < 0.0001) were associated with decreased overall survival. By multivariate analysis, only sarcomatoid growth (p = 0.0006), depth of invasion (p = 0.02), elevated CCR (CCR 2–3) (p = 0.02), and presence of inflammatory stroma (p = 0.04) were significant variables associated with decreased overall survival. DPM form a spectrum of indolent to highly aggressive tumours. Solid epithelioid/deciduoid tumours have a prognosis intermediate between biphasic mesotheliomas and invasive TPM. The presence and degree of invasion, sarcomatoid features, and inflammatory stroma are poor prognostic indicators.

Polyomavirus (BK)-associated pleomorphic giant cell carcinoma of the urinary bladder: A case report

This report describes the morphological features of a pleomorphic giant cell carcinoma with focal trophoblastic differentiation of the urinary bladder in a male, 12 years post living related donor renal transplant. The voided urine cytology demonstrated rare decoy cells admixed with markedly atypical urothelial cell clusters, papillae and giant cells. Cystoprostatectomy demonstrated a nodular mass involving the trigone and right lateral-posterior wall, adjacent to the ureteral orifice. Hematoxylin-eosin stained sections showed two synchronous malignancies: (a) pleomorphic giant cell carcinoma with focal trophoblastic differentiation of the urinary bladder, metastatic to the omentum and (b) prostatic adenocarcinoma, Gleason score 3+4=7, involving the right prostate lobe. Strong diffuse expression of polyomavirus large T antigen was demonstrated in the primary and metastatic pleomorphic giant cell carcinoma, supporting a possible role for polyomavirus (BK) in the oncogenetic pathway. The prostatic adenocarcinoma was negative for polyomavirus large T antigen. Our findings of p63, CK7 and CK903 expression in pleomorphic giant cell carcinoma suggest that the tumor is of urothelial derivation. This is the first report describing the morphological features of urinary bladder pleomorphic giant cell carcinoma with trophoblastic differentiation, positive for polyomavirus large T antigen, arising in the background of BKV reactivation.

Performance characteristics of ultrasound‐guided fine‐needle aspiration of axillary lymph nodes for metastatic breast cancer employing rapid on‐site evaluation of adequacy: Analysis of 136 cases and review of the literature

It has been demonstrated that axillary ultrasound‐guided fine‐needle aspiration (US‐FNA) has excellent positive predictive value for the axillary lymph node status of patients with breast cancer before surgery or neoadjuvant therapy and, thus, can obviate the need for sentinel lymph node biopsy in FNA‐positive patients. However, US‐FNA has only moderate sensitivity, in part because of the collection of nondiagnostic or equivocal specimens. Rapid on‐site evaluation for adequacy (ROSE) can improve definitive diagnosis rates but has not been well characterized in this setting.

Automated quantification of Ki-67 proliferative index of excised neuroendocrine tumors of the lung

BackgroundThe histopathologic distinction between typical carcinoid (TC) and atypical carcinoid (AC) of the lung is based largely on mitotic index. Ki-67 may aid in separation of these tumors, as well as the distinction from large cell neuroendocrine carcinoma (LCNEC).MethodsWe identified 55 surgically resected primary neuroendocrine lung tumors (39 TC, 7 AC, 9 LCNEC) based on mitotic rate and histologic features. Ki-67 proliferative index based on automated image analysis, tumor necrosis, nodal metastases, local or distant recurrence, and survival were compared across groups.ResultsThe mean mitotic count and Ki-67 index for TC, AC, and LCNEC were 0.1 and 2.3%, 3.4 and 16.8%, and 56.1 and 81.3% respectively. The Ki-67 index did not overlap among groups, with ranges of 0-6.7% for TC, 9.9-25.7% for AC, and 63.2-91.9% for LCNEC. Nodal metastases were identified in 4/39 (10%) TC, 2/7 (22%) AC, and 2/8 (25%) LCNEC. There was no survival difference between TC and AC, but there was a significant survival difference between LCNEC and TC and AC combined (p < 0.001). There was a step-wise increase in disease free survival with tumor grade: no TC recurred, 2/7 AC recurred or progressed (median interval 35.5 months), and all LCNEC recurred or progressed (median interval 10.1 months). No patient with TC or AC died of disease, compared to 7/8 LCNEC with follow-up data.ConclusionsWe conclude that Ki-67 index is a useful diagnostic marker for neuroendocrine tumors, with 7% a divider between AC and TC, and 50% a divider between LCNEC and AC. LCNEC is biologically different from AC and TC, with a much more aggressive course, and a high Ki-67 index.Virtual SlidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_174

A comparative study of honeycombing on high resolution computed tomography with histologic lung remodeling in explants with usual interstitial pneumonia.

BACKGROUND There is little information comparing high-resolution computed tomography (HRCT) findings in UIP with different components that make up remodeling histologically. DESIGN We compared histologic features with HRCT scans from 69 explants with UIP. The extent of 7 histologic features were semi-quantitated: respiratory-lined cysts, bronchiolectasis, pulmonary interstitial emphysema (PIE), lobular remodeling, areas resembling non-specific interstitial pneumonia (NSIP), desquamative interstitial pneumonia (DIP)-like pattern, and mucus pooling within cysts extending into surrounding parenchyma. Subpleural cystic spaces and areas of lobular remodeling were measured morphometrically. Histologic features were compared to three findings on HRCT: diagnostic pattern (UIP, probable UIP, or inconsistent with UIP pattern), degree of honeycombing, and degree of ground-glass opacities. RESULTS Histologically, respiratory-lined cysts were observed in 78%, bronchiolectasis in 83%, interstitial emphysema in 22%, lobular remodeling in 96%, NSIP-like areas in 87%, DIP-like reaction in 10%, and mucin extravasation in 78%. Morphometrically, cysts of PIE measured 6.2±2.9 mm, respiratory-lined cysts 3.5±2.4 mm, and bronchiolectatic cysts 3.3±1.5 mm. Remodeled lobules measured 3.6±1.1 mm. UIP pattern on CT correlated strongly with histologic extent of bronchiolectasis (p=0.001). HRCT honeycombing showed a positive correlation with histologic bronchiolectasis (p=0.001) and respiratory-lined cysts (p=0.001). GGO was positively associated with NSIP-like areas (p=0.02) and extravasated mucus (p=0.05). CONCLUSIONS HRCT findings typical of UIP and HRCT honeycombing correlate best with bronchiolectasis histologically. NSIP pattern is common, and is associated with CT finding of GGO.

Intimal sarcomas of the aorta and iliofemoral arteries: a clinicopathological study of 26 cases

Summary Aortic sarcomas are predominantly endoluminal tumours that are believed derived from the intima. Because of their rarity, relatively little is known about their pathological features. We report a series of 26 aortic and iliofemoral tumours with histopathological and clinical data. Of the 26 cases, there were 16 men (63.6 ± 13 years) and 10 women (58.6 ± 18 years). Tumours occurred in the abdominal aorta (13), descending thoracic aorta (8), iliac or femoral arteries (4) and ascending aorta (1). Presenting tumour manifestations included claudication or peripheral vascular disease (6), pain (5), pulsatile aneurysm (2) abdominal aortic aneurysm (AAA; 2), occluded graft (2), renal artery stenosis (1), pain from bone metastasis (1), aortic rupture (1), fever (1), weight loss (1), vasculitis (1) impotence (1), incidental finding (1) and bowel ischaemia (1). The diagnosis was not suspected clinically in any case. The tumours were sampled by endarterectomy (9), aortic resection (8), repair of aneurysm (5), and in four the diagnosis was made at autopsy. Histologically and immunohistochemically, 13 were categorised as poorly differentiated angiosarcomas, seven as undifferentiated sarcomas, three as osteosarcomas, two as myxofibrosarcomas, and one as myxoid sarcoma, not otherwise specified. The undifferentiated sarcomas and angiosarcomas were histologically similar to one another and were characterised by tumour cells within and overlying thrombus. The angiosarcomas were defined by diffuse CD31 expression with co-expression of pancytokeratin in 10 (77%). Undifferentiated sarcomas were composed of spindled and/or epithelioid cells and 71% expressed smooth muscle actin. Histological material from metastatic tumours was available in two osteosarcomas and two undifferentiated sarcomas, and showed undifferentiated pleomorphic sarcoma in all cases. In this series, half of aortic intimal sarcomas are histologically undifferentiated and express endothelial and epithelial markers (epithelioid angiosarcoma). The second largest group is undifferentiated sarcoma without immunohistochemical evidence of endothelial differentiation and frequent actin positivity. Rare types include myxofibrosarcoma and osteosarcoma.

Orphan Adhesion GPCR GPR64/ADGRG2 Is Overexpressed in Parathyroid Tumors and Attenuates Calcium‐Sensing Receptor‐Mediated Signaling

Abnormal feedback of serum calcium to parathyroid hormone (PTH) secretion is the hallmark of primary hyperparathyroidism (PHPT). Although the molecular pathogenesis of parathyroid neoplasia in PHPT has been linked to abnormal expression of genes involved in cell growth (e.g., cyclin D1, retinoblastoma, and β‐catenin), the molecular basis of abnormal calcium sensing by calcium‐sensing receptor (CaSR) and PTH hypersecretion in PHPT are incompletely understood. Through gene expression profiling, we discovered that an orphan adhesion G protein‐coupled receptor (GPCR), GPR64/ADGRG2, is expressed in human normal parathyroid glands and is overexpressed in parathyroid tumors from patients with PHPT. Using immunohistochemistry, Western blotting, and coimmunoprecipitation, we found that GPR64 is expressed on the cell surface of parathyroid cells, is overexpressed in parathyroid tumors, and physically interacts with the CaSR. By using reporter gene assay and GPCR second messenger readouts we identified Gαs, 3′,5′‐cyclic adenosine monophosphate (cAMP), protein kinase A, and cAMP response element binding protein (CREB) as the signaling cascade downstream of GPR64. Furthermore, we found that an N‐terminally truncated human GPR64 is constitutively active and a 15–amino acid–long peptide C‐terminal to the GPCR proteolysis site (GPS) of GPR64 activates this receptor. Functional characterization of GPR64 demonstrated its ability to increase PTH release from human parathyroid cells at a range of calcium concentrations. We discovered that the truncated constitutively active, but not the full‐length GPR64 physically interacts with CaSR and attenuates the CaSR‐mediated intracellular Ca2+ signaling and cAMP suppression in HEK293 cells. Our results indicate that GPR64 may be a physiologic regulator of PTH release that is dysregulated in parathyroid tumors, and suggest a role for GPR64 in pathologic calcium sensing in PHPT.

Real-time MR Imaging Guidance for Percutaneous Core Biopsy of US- and CT-negative Lesion

Biopsies traditionally are performed under ultrasound (US), computed tomography (CT), or fluoroscopic guidance. In situations in which lesions are difficult to visualize with US or CT guidance, magnetic resonance (MR) imaging often can provide better imaging results. The authors describe a case in which a recurrent calf mass not well visualized under fluoroscopy, CT, or US was identified on MR imaging. In the absence of real-time needle visualization, percutaneous interventions under MR guidance have been limited by prohibitively long imaging times. A novel guidance system providing real-time MR guidance of needle position was used to procure a core biopsy specimen of the lesion.

Non-Neoplastic Findings

The category “negative for intraepithelial lesion or malignancy” is used for specimens that show a spectrum of nonneoplastic changes, including those associated with protective and reactive responses to inflammation, hormonal alterations, and colonizing or infectious organisms. Recognition of the wide variety of normal cellular presentations is key for the accurate discrimination from neoplastic conditions. Many characteristic patterns of reaction in normal cells can be important clues to the underlying causative process. Some of these patterns have features which are also seen in neoplasia, hence recognition of the key reactive changes is essential for overall accuracy. An expanded variety of “normal” findings as well as non-neoplastic mimics of classic epithelial abnormalities are included in this chapter, providing a more complete representation of the morphologic variations that can be encountered in cervical cytology preparations.