• Epithelioid angiomyolipoma of the liver: case report and review of the literature

      Tryggvason, Geir; Blöndal, Sigurdur; Goldin, Robert D; Albrechtsen, Jörgen; Björnsson, Jóhannes; Jónasson, Jón G (Munksgaard, 2004-09-01)
      Hepatic angiomyolipoma is a rare tumor. Here we describe a case and review the literature.
    • Gastrointestinal stromal tumors in Iceland, 1990-2003: the icelandic GIST study, a population-based incidence and pathologic risk stratification study

      Tryggvason, Geir; Gislason, Hjortur G; Magnusson, Magnus K; Jonasson, Jon G; Department of Pathology, Landspitali University Hospital, Reykjavik, Iceland. (Wiley-Liss, 2005-11-01)
      Gastrointestinal stromal tumor (GIST) is a newly defined clinical and pathologic entity. This study examines the whole population-based incidence of GIST as well as pathologic risk stratification schemes. All patients diagnosed in Iceland with a gastrointestinal mesenchymal tumor over the years 1990-2003 were evaluated with an immunohistochemical panel including staining for c-kit. The age-adjusted incidence of GIST was calculated. Size, mitotic rate per 50 HPF and various other pathologic parameters were evaluated. Each tumor was categorized into 1 of 4 recently defined NIH risk stratification categories. Fifty-seven of the mesenchymal gastrointestinal tumors were positive for c-kit and therefore categorized as GIST. The annual incidence for the study period is 1.1 per 100,000. The median age of patients was 65.8 years and median tumor size was 4.6 cm. Only 2 of 35 gastric tumors fall into the NIH high-risk category while half of the nongastric tumors (11 of 22) fall into this high-risk category. Eight of the 57 tumors (14%) metastasized, 7 of which were nongastric. The positive predictive value for malignant behavior of the high-risk category is 46%. The negative predictive value of low- and very-low-risk NIH category is 100%. Pathologic predictors of malignant behavior are tumor size, mitotic rate, mucosal disruption, necrosis and high cellularity. Nongastric GISTs are clearly at much higher risk of a malignant behavior than gastric GISTs. This population-based GIST study estimates the incidence of GISTs at 1.1 per 100,000 and furthermore supports the NIH consensus categories for the prediction of malignant behavior of GISTs.
    • Hearing in older adults with exfoliation syndrome/exfoliation glaucoma or primary open-angle glaucoma

      Tryggvason, Geir; Jonasson, Fridbert; Cotch, Mary Frances; Li, Chuan-Ming; Hoffman, Howard J.; Themann, Christa L.; Eiriksdottir, Gudny; Sverrisdottir, Jóhanna Eyrún; Harris, Tamara B.; Launer, Lenore J.; et al. (Wiley-Blackwell, 2016-03)
      PURPOSE: To determine whether adults, aged 66-96 years, with exfoliation syndrome (XFS)/exfoliation glaucoma (XFG), or primary open-angle glaucoma (POAG) have poorer hearing than controls of similar age. METHODS: Case (XFS/XFG and POAG) and control status was diagnosed in the Reykjavik Glaucoma Studies (RGS) using slit-lamp examination, visual field testing and optic disc photographs; the RGS data were merged with the Age, Gene/Environment Susceptibility-Reykjavik Study that collected hearing data using air-conduction, pure-tone thresholds obtained at 0.5, 1, 2, 3, 4, 6 and 8 kHz categorized by better ear and worse ear, based on pure-tone averages (PTAs) calculated separately for low and middle frequencies (PTA512 - mean of thresholds at 0.5, 1 and 2 kHz) and high frequencies (PTA3468 - mean of thresholds at 3, 4, 6 and 8 kHz). Multivariable linear regression was used to test for differences in PTAs between cases and controls. RESULTS: The mean age for 158 XFS/XFG cases (30.4% male) was 77.4 years, 95 POAG cases (35.8% male) was 77.9 years, and 123 controls (46.3% male) was 76.8 years. Using multivariable linear regression analysis, there were no consistent, statistically significant differences in PTAs between the two case groups and controls in either the low- or high-frequency range, even when stratified by age group. CONCLUSION: Among the older individuals examined in this study hearing loss is highly prevalent and strongly associated with male gender and increasing age. As we did not find consistent statistically significant difference in hearing between cases and controls the diagnosis of XFS/XFG or POAG does not as such routinely call for audiological evaluation.
    • Salivary gland tumours in Iceland 1986-2015: a nationwide epidemiological analysis over a 30-year time period.

      Aegisdottir, Anna Lilja; Tryggvason, Geir; Jonsdottir, Anna Margret; Jonasson, Jon Gunnlaugur; 1Faculty of Medicine, University of Iceland, Reykjavik, Iceland. 2Department of Otorhinolaryngology, The National University Hospital of Iceland, Reykjavik, Iceland. 3Department of Pathology, The National University Hospital of Iceland, Reykjavik, Iceland. (Wiley, 2020-10-16)
      Salivary gland tumours (SGT) are a vast and heterogenous group of neoplasms. There is a relative lack of comprehensive nationwide epidemiological studies on the subject. The aim of this nationwide analysis was to gain insight into epidemiological traits, such as site, incidence and histological subtypes of SGT in general. Patients diagnosed with a primary SGT between 1986 and 2015 were identified from The Icelandic Cancer Registry and registries from all pathology departments in Iceland. Information on age, sex, tumour location and histology was retrieved from pathology reports. A total of 687 patients were diagnosed with a SGT, 609 (89%) were benign and 78 (11%) malignant. 9% of parotid gland tumours, 22% of submandibular gland tumours and 26% of minor SGT were malignant. The most common malignant tumours were mucoepidermoid carcinoma, acinic cell carcinoma and adenoid cystic carcinoma. The incidence of benign SGT was 4.9 per 100 000 among men and 7.0 per 100 000 among women. The incidence of malignant tumours was 0.59 per 100 000 for men and 0.79 per 100 000 for women. The proportion of malignant SGT is lower than most often reported. Only 10% of parotid gland tumours, 20% of submandibular gland tumours and 25% of minor salivary gland tumours are malignant. Keywords: Salivary gland; epidemiology; histology; oncology; tumour.