Matthew J. Wasco

Regulation of pathogenic IL-17 responses in collagen-induced arthritis: roles of endogenous interferon-gamma and IL-4

IntroductionInterleukin (IL)-17 plays an important role in the pathogenesis of rheumatoid arthritis and the mouse model collagen-induced arthritis (CIA). Interferon(IFN)-γ and IL-4 have been shown to suppress Th17 development in vitro, but their potential immunoregulatory roles in vivo are uncertain. The goals of this study were to determine the relationship between Th17 responses and disease severity in CIA and to assess regulation of IL-17 by endogenous IFN-γ and IL-4.MethodsDBA1/LacJ mice were immunized with type II collagen in complete Freunds adjuvant (CFA) to induce arthritis, and treated with neutralizing antibody to IFN-γ and/or IL-4. Systemic IL-17, IFN-γ, and IL-4 were measured in serum. At the peak of disease, cytokine production was measured by ELISA of supernatants from spleen, lymph node and paw cultures. Paws were also scored for histologic severity of arthritis.ResultsJoint inflammation was associated with a higher ratio of systemic IL-17/IFN-γ. Neutralization of IFN-γ accelerated the course of CIA and was associated with increased IL-17 levels in the serum and joints. The IFN-γ/IL-4/IL-17 responses in the lymphoid organ were distinct from such responses in the joints. Neutralization of IL-4 led to increased arthritis only in the absence of IFN-γ and was associated with increased bone and cartilage damage without an increase in the levels of IL-17.ConclusionsIL-4 and IFN-γ both play protective roles in CIA, but through different mechanisms. Our data suggests that the absolute level of IL-17 is not the only determinant of joint inflammation. Instead, the balance of Th1, Th2 and Th17 cytokines control the immune events leading to joint inflammation.

Nested variant of urothelial carcinoma: a clinicopathologic and immunohistochemical study of 30 pure and mixed cases

Nested urothelial carcinoma (UC) is a rare histologic variant of UC, characterized by deceptively bland histologic features resembling von Brunns nests but usually with a poor outcome. In our experience, this variant is frequently misclassified or underrecognized as its clinicopathologic spectrum is not well defined. In addition, its relationship to usual UC and response to traditional bladder cancer management are largely unknown. Herein we report the largest series to date of 30 UC cases with pure or predominant nested morphology to identify its associated histopathologic findings, clinical outcome, and immunophenotype. Patient age ranged from 41 to 83 years (average, 63 years) with a male-female ratio of 2.3:1. The architectural pattern of the nested component ranged from a predominantly disorderly proliferation of discrete, small, variably sized nests (90%) to focal areas demonstrating confluent nests (40%), cordlike growth (37%), and cystitis cystica-like areas (33%) to tubular growth pattern (13%). The deep tumor-stroma interface was invariably (100%) jagged and infiltrative. Despite overall banal cytology, tumor nests demonstrated focal random cytologic atypia (90%) and focal high-grade cytologic atypia centered within the base of the tumor (40%). The tumor stroma ranged from having minimal stromal response to focally desmoplastic and myxoid. A component of usual UC was present in 63% of cases. The nested component demonstrated an immunophenotype identical to usual UC, with CK7, CK20, p63, and CK903 expression in 93%, 68%, 92%, and 92% of cases, respectively. At resection, all but 1 case demonstrated invasive carcinoma-9% into lamina propria, 4% into muscularis propria, 65% into perivesical fat, and 17% into adjacent organ(s). When compared with pure high-grade UC, nested UC was associated with muscle invasion at transurethral resection (31% versus 70%; P < .0001), extravesical disease at cystectomy (33% versus 83%; P < 0.0001), and metastatic disease (19% versus 67%; P < .0001). Follow-up was available on 29 patients (97%) with a median of 12 months (range, 1-31 months) of follow-up; 3 (10%) died of disease, 16 (55%) are alive with persistent or recurrent disease, and 10 (34%) are alive without disease. Response to neoadjuvant chemotherapy was observed in 2 (13%) of 15 patients. Nested UC seen either in pure form or with a component of usual UC had similarly unfavorable outcomes (P = .78). Increased awareness and familiarity with the clinicopathologic spectrum is critical for confident recognition and adequate management of this very aggressive variant of UC.

Cluster analysis of immunohistochemical profiles delineates CK7, vimentin, S100A1 and C-kit (CD117) as an optimal panel in the differential diagnosis of renal oncocytoma from its mimics

Carvalho J C, Wasco M J, Kunju L P, Thomas D G & Shah R B
(2011) Histopathology58, 169–179

The expression of MUM1 in cutaneous T-cell lymphoproliferative disorders

MUM1 is a member of the interferon regulatory factor family of transcription factors. It is normally expressed in plasma cells, late B cells, and activated T cells, and has been described in several B-cell malignancies. Although its expression has been reported in some T-cell neoplasms, the full range and character of expression have not been explored. We studied 58 cases of T-cell lymphoproliferative lesions, including systemic and cutaneous anaplastic large cell lymphoma, lymphomatoid papulosis (LyP), mycosis fungoides (MF), MF with large cell transformation, and Sézary syndrome (SS). Nearly all cutaneous (5/5) and systemic anaplastic large cell lymphomas (4/5) were positive for MUM1, mainly in the large cell population. Similarly, 12 of 16 types A and C LyP showed MUM1 reactivity in greater than 50% of the large cells. Focal MUM1 staining was seen in 3 type B LyP, mostly in reactive lymphoid cells. All 9 MF with large cell transformation expressed MUM1 in large cells, where it paralleled CD30 expression. In comparison, most MF (11/12) were MUM1 negative. Interestingly, all SS cases (8/8) were MUM1 positive, 3 of which demonstrated diffuse staining. There was a significant difference in MUM1 expression between MF and SS groups as well as between MF and large cell transformation of MF groups (P < .001 for both). In summary, MUM1 is not helpful in separating different types of CD30-positive lymphoproliferative disorders. Potentially, MUM1 could serve as an adjunct marker for SS and/or large cell transformation of MF.

Expression of γ-H2AX in melanocytic lesions

gamma-H2AX is a marker of activated DNA damage and is overexpressed in many malignancies and their precursor lesions. Previous studies have demonstrated the expression of gamma-H2AX in melanoma and dysplastic nevus, but its diagnostic and prognostic utility in a full range of melanocytic lesions has not been fully studied. In the current study, we investigated gamma-H2AX expression in a total of 162 melanocytic lesions. We found that gamma-H2AX was observed at higher levels (percentage and intensity of staining) in melanoma in situ (12/13), primary cutaneous melanoma (32/33; with the exception of desmoplastic melanoma), and metastatic melanoma (58/62), which was statistically different from that in benign nevus (7/9), dysplastic nevus (6/10), and Spitz nevus (5/9) considered together (P < .0001). Of note, desmoplastic melanoma (20/26) demonstrated weak or negative gamma-H2AX staining. The expression of gamma-H2AX did not show significant correlation with many melanoma prognostic factors, including Breslow depth, mitotic rate, and sentinel lymph node status. Except for desmoplastic melanoma, no difference in gamma-H2AX levels was observed among various melanoma subtypes. The overexpression of gamma-H2AX in melanoma as opposed to nevus indicates its possible role in melanomagenesis. Based on the overlap in subsets of nevi and melanomas, the potential clinical utility of this antibody remains uncertain until further studies have been carried out in a larger cohort of melanocytic lesions, including borderline cases.

Utility of antiphosphorylated H2AX antibody (gamma-H2AX) in diagnosing metastatic renal cell carcinoma.

The differential diagnosis of metastatic renal cell carcinoma (RCC) includes, although is not limited to, hepatocellular carcinoma (HCC) and adrenocortical carcinoma (ACC) due to overlapping morphology. Immunohistochemical markers, including RCC marker (RCC-Ma) have been employed with varying success in the differential diagnosis of RCC. Our preliminary tissue microarray study demonstrated that γ-H2AX, an antibody that specifically reacts with phosphorylated histone H2AX, stained many primary RCC strongly and did not stain HCC or ACC, prompting us to evaluate its utility in these tumors and to compare it with RCC-Ma. Seventy-one cases of metastatic RCC, 18 HCC, and 21 ACC were stained with γ-H2AX and RCC-Ma and the sensitivity and specificity of each marker was compared. RCC-Ma demonstrated a membranous pattern of staining in 70% of RCC cases (50/71), and none of the ACC or HCC (100% specificity for RCC). Nuclear staining by γ-H2AX had a similar sensitivity of 70% for RCC but a lower specificity of 77%, as it was seen in 1 of 18 HCC (5%) and 8 of 21 (38%)ACC. In metastatic RCC, 83% (39/47) of tumors with a higher nuclear grade stained with γ-H2AX, compared with 46% (11/24) of low nuclear grade (equivalent of Fuhrman 2 and lower) tumors. RCC-Ma had a similar rate of staining in low and high-grade tumors, 75% (18/24) and 68% (32/47), respectively. More importantly, of RCCs that were negative for RCC-Ma, 14 of 21 (67%) were positive for γ-H2AX. The results suggest γ-H2AX is a useful adjunct in diagnosis of metastatic RCC when RCC-Ma is negative and in higher grade RCC, which are often a diagnostic challenge. A nuclear pattern of staining of γ-H2AX has a comparable sensitivity with RCC-Ma, and the interpretation is easier and more reliable. RCC-Ma is 100% specific for RCC, but only when a membranous pattern of staining is interpreted as positive.

Multiple Adverse Histological Features Increase the Odds of Under Staging T1 Bladder Cancer

PURPOSE The clinical under staging of T1 bladder cancer potentially delays therapy and undermines survival. In this study we evaluated clinicopathological features to aid in the identification of patients with clinical T1 bladder cancer at risk for under staging. MATERIALS AND METHODS We identified patients diagnosed with clinical T1 bladder cancer who underwent cystectomy within 4 months. Muscularis propria was present and uninvolved in initial biopsies or patients had a re-staging biopsy with muscle [corrected] present. Under staging was defined as pT2 or greater, N+ or M+ disease at radical cystectomy. A logistic regression multivariable model was used for the risk of under staging. Overall survival was assessed using the Kaplan-Meier method. RESULTS Of 95 patients 26 (27%) had under staged disease. Median followup was 24 months. Compared to accurately staged cases under staged cases were more likely to have muscularis mucosae invasion (54% vs 19%, p = 0.001), mixed histology (42% vs 17%, p = 0.02) and urethral involvement (31% vs 10%, p = 0.03). In a multivariable model muscularis mucosae invasion increased the odds of under staging 9-fold (95% CI 1.5-54.5, p = 0.01). The cumulative association of these risk factors increased the odds of under staging 20-fold (95% CI 1.8-217, p = 0.0029). Median overall survival (years) was lower in patients with under staged disease (1.4 vs 10.6, p <0.001), those with muscularis mucosae invasion (2.2 vs 6.5, p = 0.04) and those with urethral involvement (25th percentile 0.8 vs 2.0, p = 0.01). CONCLUSIONS Under staging adversely impacts survival. Muscularis mucosae invasion, urethral involvement and mixed histology cumulatively increase the risk of under staging, and may be valuable in counseling patients regarding early, aggressive intervention.

IMP‐3 expression in melanocytic lesions

Background: Insulin‐like growth factor‐II mRNA‐binding protein 3 (IMP‐3 ), a member of the insulin‐like growth factor mRNA‐binding protein family, is expressed in several human malignancies, including melanomas. However, the expression of IMP‐3 has not been explored in melanoma in situ, various histologic subtypes of invasive melanomas and atypical Spitz tumors.

Leiomyoma of the Adrenal Gland Presenting as a Non-Functioning Adrenal Incidentaloma: Case Report and Review of the Literature

A 31-year-old woman was incidentally found to have a large right adrenal mass by computed tomography imaging and underwent a workup that included endocrinological evaluation and positron emission tomography imaging. Laboratory results revealed the mass to be non-functioning. Imaging studies revealed a 9-cm heterogeneous mass that was not FDG avid. Because of concern for adrenal cortical carcinoma, the patient underwent a successful right adrenalectomy. Pathology examination demonstrated an 11-cm circumscribed mass consisting of uniform spindle cells without nuclear pleomorphism, necrosis, or mitotic activity. The diagnosis of leiomyoma was supported by a panel of immunohistochemical stains. Adrenal leiomyomas have been reported in the literature, although most are small and not preoperatively suspicious for malignancy. This case illustrates that benign tumors such as leiomyomas, when large and heterogeneous on imaging, can clinically mimic adrenal cortical carcinomas and should be included in the differential diagnosis of adrenal incidentalomas.

Benign Diseases and Neoplasms of the Penis

This article provides comprehensive review of benign diseases and neoplastic conditions of the penis. It describes and provides representative images of clinical, key pathologic features and ancillary techniques to aid in differential diagnoses. It examines these diseases from the epidemiologic standpoint, looks at environmental and genetic factors, and outlines the new histologic entities for penile neoplasms with distinct outcomes and clinical behavior that have been proposed in recent years.