Arthur Ott

Germline mutations in BAP1 predispose to melanocytic tumors

Common acquired melanocytic nevi are benign neoplasms that are composed of small, uniform melanocytes and are typically present as flat or slightly elevated pigmented lesions on the skin. We describe two families with a new autosomal dominant syndrome characterized by multiple, skin-colored, elevated melanocytic tumors. In contrast to common acquired nevi, the melanocytic neoplasms in affected family members ranged histopathologically from epithelioid nevi to atypical melanocytic proliferations that showed overlapping features with melanoma. Some affected individuals developed uveal or cutaneous melanomas. Segregating with this phenotype, we found inactivating germline mutations of BAP1, which encodes a ubiquitin carboxy-terminal hydrolase. The majority of melanocytic neoplasms lost the remaining wild-type allele of BAP1 by various somatic alterations. In addition, we found BAP1 mutations in a subset of sporadic melanocytic neoplasms showing histological similarities to the familial tumors. These findings suggest that loss of BAP1 is associated with a clinically and morphologically distinct type of melanocytic neoplasm.

Primary mucosal melanomas of the nasal cavity and paranasal sinuses

We present 14 patients with primary sinonasal melanomas (SM) identified from 1984–1997 in our archives (11/14 lateral nose, 1/14 nasal septum, 2/14 paranasal sinuses; 8M/6F, mean age 67.7 years, range 39–88 years). Survival was poor (median 9 months) with death related to extensive local disease and/or widespread hematogenous metastases. The following histological subtypes were identified in descending order: amelanotic small blue cell, pleomorphic, epithelioid, spindle cell and myxoid. High mitotic rate and vascular invasion, absence of tumor‐infiltrating lymphocytes and regression were features shared by all SM. Negative staining of B‐ and T‐cell markers, LCA, neuroendocrine markers such as NSE, chromogranin and synaptophysin, and CK‐negativity excluded olfactory neuroblastoma, small cell undifferentiated carcinoma, and lymphoma. S‐100 protein was expressed in all SM, but demonstrated variable staining intensity with areas of complete negativity. HMB45 was strongly and uniformly (>80%) expressed in all undifferentiated small blue cell SM. The pigmented SM were predominantly HMB45‐negative. The strong HMB45 staining in amelanotic small blue cell SM is explained by the reaction of HMB45 antibody with an oncofetal antigen found in immature melanosomes. In these poorly differentiated amelanotic malignant melanomas, antibody to HMB45 proved to be a superb diagnostic marker. We therefore strongly advocate the inclusion of HMB45 antibody in the panel of antibodies for initial work‐up of undifferentiated mucosal neoplasms, since a negative S‐100 stain in small biopsy material may result in incorrect classification of these neoplasms.

CD44 expression in sinonasal melanomas: is loss of isoform expression associated with advanced tumour stage?

The expression of the adhesion molecule CD44 was examined in 14 primary sinonasal melanomas (SMs), aggressive neoplasms with short survival times, as CD44 overexpression has been linked to poor survival in human cancers. Immunohistochemistry was performed on formalin‐fixed, paraffin‐embedded sections with CD44 isoform‐specific monoclonal antibodies to the CD44 standard (s) and variant isoforms (v) v5 and v6. CD44s, v5, and v6 were strongly expressed in a membranous pattern in SM in situ, early invasive SM, and in uninvolved respiratory/squamous epithelium. In invasive SM, membranous CD44s expression was identified in a large proportion of melanoma cells. Membranous staining of CD44v5 and v6 was lost in invasive SM, independently of the histological subtype. Diffuse cytoplasmic staining was observed focally in invasive SM and loss of cytoplasmic expression of CD44v6 and v5 was associated with advanced tumour stage in the linear‐by‐linear association test (p = 0·042 and 0·066, respectively). CD44s may not be important for malignant transformation, as it is expressed in both benign and malignant melanocytes. Loss of membranous CD44 isoform expression in widely invasive SM suggests that loss of cellular adhesion facilitates matrix and vascular infiltration and dissemination of sinonasal melanoma cells. Copyright

Syringocystadenocarcinoma papilliferum in situ originating from the perianal skin

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Clinical epidemiology of invasive cutaneous malignant melanoma in the Austrian province Styria in the years 2001-2003 and its relationship with local geographical, meteorological and economic data.

Background:Melanoma incidence rates vary within Europe. The highest incidences are reported in Scandinavia, the lowest in the southern parts, but incidences themselves also vary within the different countries. Objective:We investigated the incidence of invasive cutaneous melanoma in Styria, a province of Austria, in the years 2001–2003. Methods:Data from 1,082 patients, 511 males and 571 females (mean age 58.2 years) with primary melanoma were collected. For each patient, information regarding residence was available, and therefore the geographic distribution of melanoma on district level was investigated with particular reference to the mean number of sun hours, mean altitude, number of companies with more than 200 employees and median income. Results:The mean annual incidence (age-standardized rate) was 24.5 per 100,000 (95% CI: 22.4–26.6), lifetime risk 1 in 52. Districts with a higher number of sun hours and higher altitude showed lower melanoma incidences. Higher median income was associated with higher melanoma incidence (p < 0.001). Conclusion:The high incidence of invasive melanoma in Styria is unclear and a causal relationship between higher income and melanoma incidence remains speculative. Further investigations, especially concerning lifestyle and environmental factors, may unravel additional causative factors.

Ratio of marked and excised sentinel lymph nodes and scintigraphic appearance time in melanoma patients with negative sentinel lymph node

AIM Metastases can occur in up to 15% of all melanoma patients with negative sentinel lymph node examination (SN -). We retrospectively investigated the number of preoperatively marked sentinel lymph nodes (SNs) with lymphoscintigraphy and effectively surgically removed SNs in SN--patients with cutaneous melanoma >or=0.5 mm. Ratio of these parameters was calculated and impact of this ratio as well as impact of scintigraphic appearance time (SAT) on disease progression was studied. MATERIALS AND METHODS Data on 122 SN--patients--70 women (58%), mean age 56.5 years--were analyzed. Mean follow-up time was 58 months. RESULTS Mean tumour thickness of all patients was 2.3 mm. In 51 patients (42%) the number of SNs marked in lymphoscintigraphy was higher than excised in surgery, in 47 patients (38%) the same number as marked was excised and in 24 patients (20%) a lower number was marked than excised. Metastases occurred in 17 patients (14%) after a mean time of 24.8 months. Mean tumour thickness (5.4 mm) was significantly higher in these patients than in the other patients (p = 0.000). Ratio of marked and excised SNs had no influence on disease progression; the only parameter influencing outcome was tumour thickness (p = 0.000). Short SAT was significantly associated with higher tumour thickness (p = 0.004). CONCLUSION Our study indicates that, in routine clinical practice, it suffices to harvest the first SN, as the ratio of marked and excised SNs has no impact on disease progression.

Natural history of invasive cutaneous melanoma in Styria, Austria 2001–2003

Background: Rising melanoma incidences have created the need of assessment of epidemiological and clinical data.

Urothelial carcinoma with abundant myxoid stroma: evidence for mucus production by cancer cells

Dear Editor, Urothelial carcinoma has a propensity for aberrant differentiation, with squamous and glandular being the most common histological variants [1]. Notably, divergent differentiation occurs more frequently in high-grade and high-stage tumours [2]. Recently, urothelial carcinoma with abundant myxoid stroma has been identified as a new histological variant [3]. The origin of stromal mucin, however, is currently unclear. A 66-year-old male with history of gastric signet ring cell carcinoma presented with haematuria and unspecific lower abdominal pain. Cystoscopy disclosed a polypoid lesion, measuring 3 cm in largest diameter, which extended from the bladder wall into the lumen and was removed by transurethral resection. Histology revealed non-invasive papillary urothelial lowgrade carcinoma with mild architectural and cytologic atypia. Parts of the lesion showed infiltration of the lamina propria by high-grade cancer cells. The most striking morphological feature was an abundant myxoid stroma which covered approximately 30 % of the lesion. Notably, mucin production was evident also in non-invasive cancer areas, as documented by the presence of intercellular mucin leading to a cord-like and ultimately microcystic pattern (Fig. 1a–c). Neoplastic glandular epithelium was not observed. Histochemical stains for Alcian blue and PAS showed positivity of extracellular mucinous material, but reactivity was also observed within the cytoplasm of cancer cells (Fig. 1d–e). Upon immunohistochemistry, the tumour cells were positive for p63, keratin 7 and 20, E-cadherin, MUC1, MUC2 and MUC5AC (Fig. 1f–h). Electron microscopy performed on formalin-fixed, paraffin-embedded material disclosed nonmembrane-bound cytoplasmatic globules, consistent with mucus droplets (Fig. 2). Prominent myxoid stroma has been described as pseudosarcomatous stroma reaction associated with urothelial carcinoma and as sarcomatoid urothelial carcinoma. Recently, Tavora et al. [3] introduced the term “urothelial carcinoma with abundant myxoid stroma” for otherwise typical urothelial tumours showing marked extracellular mucin deposition which should not be confused with primary or secondary adenocarcinoma of the bladder as well as benign lesions, such as cystitis glandularis with intestinal metaplasia, endocervicosis and villous adenomas [3, 4]. Although their series was small and follow-up limited, the authors suggested that this new variant might be less aggressive compared to conventional urothelial carcinoma. Most probably, Cox et al. [5] described the same tumour variant under the name “invasive urothelial carcinoma with chordoid features”. Their tumours were similarly characterized by prominent myxoid stroma and intercellular mucin deposition, leading to cord-like epithelial architecture and microcystic pattern, as was also shown for our case. According to Tavora et al. [3], the origin of mucin is unclear, particularly in the absence of overt glandular epithelium. Our case, however, clearly shows mucin production by otherwise typical urothelial cancer cells in both invasive and non-invasive tumour areas. This finding illustrates the capacity of urothelial cancer cells to show divergent, i.e. aberrant mucinous differentiation. In our opinion, M. M. Gilg :B. Wimmer :A. Ott :C. Langner (*) Institute of Pathology, Medical University of Graz, Auenbruggerplatz 25, 8036 Graz, Austria e-mail: cord.langner@medunigraz.at Virchows Arch (2012) 461:99–101 DOI 10.1007/s00428-012-1253-8

Pancreatic adenocarcinoma with multiple eosinophilic extracellular deposits consistent with noncalcified psammoma bodies

Dear Editor, Adenocarcinomas commonly show extracellular mucin deposits, which, e.g., in breast cancer, may undergo secondary degenerative changes such as calcification. Psammoma bodies representing lamellated calcifications are a common morphologic feature of papillary carcinoma of the thyroid, serous adenocarcinoma of the ovary, and meningiomas. A 63-year-old male presented with unspecific epigastric pain and obstructive jaundice. Abdominal computed tomography revealed a mass lesion within the head of the pancreas, measuring 1.8 cm in the largest diameter, with infiltration of the duodenal wall, stricture of the distal bile duct, and dilatation of the biliary system. In addition, cancer spread to regional lymph nodes and liver was noted (Fig. 1). Endoscopy disclosed ulceration of the duodenal mucosa by penetrating tumor and multiple biopsies were obtained. Upon histology, the tumor turned out to be a poorly differentiated ductal adenocarcinoma. The tumor infiltrated the duodenal mucosa, showed multifocal lymphatic permeation, and was characterized by multiple eosinophilic extracellular deposits that were commonly, yet not invariably surrounded by cancer cells (Fig. 2a–b). The deposits were PAS-positive (Fig. 2c) and appeared lamellated, consistent

Abstract LB-125: Germline mutations in BAP1 predispose to melanocytic nevi and melanoma

Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL We describe an autosomal-dominant syndrome characterized by multiple non-pigmented, exophytic melanocytic nevi and an increased susceptibility for melanoma, caused by germline mutations in the histone deubiquitinase BAP1. To identify the causative alterations, we performed comprehensive genomic analyses in two unrelated families with numerous dermal nevi composed largely of large, epithelioid melanocytes with abundant amphophilic cytoplasm and large, pleomorphic, vesicular nuclei with prominent nucleoli. Both families each had one proband with uveal melanoma, and three probands in one family had cutaneous melanoma. Array-based comparative genomic hybridization (aCGH) revealed losses of parts of or the entire chromosome 3 in 11 of 22 neoplasms studied. Genotypic analyses revealed that the deletions invariably affected the chromosome from the unaffected parent. Genome partitioning of the minimally deleted region on chromosome 3p21 followed by massively parallel sequencing revealed two different inactivating germline mutations of the BAP1 tumor suppressor gene that in both families segregated with the phenotype. In almost all tumors the remaining wild type BAP1 allele was eliminated by deletion, separate inactivating mutations, or loss of heterozygosity. 35 of 40 nevi (88%) showed mutations in BRAF, while the uveal melanomas had mutations in GNAQ. Our data identify BAP1 as a highly penetrant susceptibility gene for melanocytic neoplasia. Somatic BAP1 mutations have recently been reported in uveal melanoma and linked to the metastatic phenotype. Our observation of frequent bi-allelic inactivation of BAP1 in nevi indicates that the role of BAP1 in melanocytic neoplasia is more complex, and may differ depending on other factors such as the type of melanocyte (uveal or cutaneous) and the co-existing oncogenic mutation. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr LB-125. doi:10.1158/1538-7445.AM2011-LB-125