The 20th century was the most eventful period in the history of Zemun Hospital and it brought many changes. Working through out both world wars, the hospital staff aided those who were wounded or ill, both soldiers and civilians. Throughout this period, the hospital worked in three different countries, under various administrations and owners.

Aim: To determine prognosic significance of RAS oncogene mutation detection in patients with metastatic colorectal carcinoma (mCRC). Introduction: CRC is still third most common cancer of both genders and second cause of death from malignancy in Western countries. In recent years, detecting RAS mutation in mCRC tumor tissue has became an imperative in selecting patients for monoclonal antibodies targeted therapy to Epidermal Growth Factor Receptor (EGFR). Nevertheless, there is no consensus regarding prognostic relevance of determining RAS status in patients with mCRC. Material and methods: Study included 116 patients with surgicaly resected CRC at Oncology Insitute of Vojvodina between January and December 2016. KRAS mutation detection was performed in formalin-fixed paraffin embeded tumor tissue samples processed by real-time chain polymerase reaction (real-time PCR) and applyng Cobas® KRAS Mutation Test and Cobas® 4800 System for detection of mutations in codons 12/13 and 61 of KRAS gene. Results: Average age in tested population was 65 years, with a male gender predominance (66.4%). Presence of KRAS mutation was found in 50.9% patients: 44.8% in codons 12/13, 4.3% in codon 61 and 1.7% in both codons 12/13 and 61. RAS mutated colorectal carcinomas (n=59) compared with RAS wildtype colorectal cancers, were significantly associated with male gender, moderately differentiated tumors, lymphovascular invasion and local nodal metastases. Conclusion: Our results show that, beside predictive, KRAS can also have prognostic significance regarding risk assesment for lymphovascular invasion and presence of local and distant metastases.

Aim: Immunohistochemistry findings along with clinical features, are significantly important in differentiating the Extrapleural SFT in the neck, from other well-circumscribed mesenchymal neoplasms at this locations. Introduction: We present a rare case of a Extrapleural SFT in a 57 years old man in the neck, without significant past medical history. Material and Methods: The patient had a painless slow growing tumor, in right sight of the neck, diagnosed with physical examination. Total excision with local anesthesia was done, without previously biopsy of the tumor and other clinical investigations. Standard procedures for histology and immunohistochemical stains were done. Results: Tumor was well circumscribed, encapsulated measuring 5,5x4x4 cm. On section, the cut surface had a multinodular, whitish and firm appearance. On microscopic examination tumor was composed of alternating hypocellular and hypercellular areas separated from each other by thick bands of collagen and branching haemangiopericitoma like vessels. The tumor cells were round to spindle-shaped with little cytoplasm, indistinct borders, dispersed chromatin within vesicular nuclei. Area of myxoid change and subcapsular focus of hemorrhage was present, and 2 mitoses/10 HPF were found. Immunohistochemistry revealed diffuse positivity for CD34, Vimentin and BCL2, focal positivity for CD99, S100, SMA, and negativity for CKWS and EMA. Ki67 showed low proliferating index 3-5%. Conclusion: Although most cases of SFT are benign, there is no strict correlation between morphology and behavior, so patients with extrapleural solitary fibrous tumor have need of long-term post-resection follow-up. Further studies are needed to determine the optimal management of these neoplasms.

Pulmonary Langerhans cell histiocytosis (PLCH) is a rare disease of unknown etiology, which most commonly affects men, smokers, aged from 20 to 40. It is diagnosed by histological analysis of material obtained by lung biopsy, with immunohistochemical proving of Langerhans cells. The aim of this research is to determine pathohistological characteristics of PLCH and analyzing demographic, clinical and radiological parameters. Retrospective analysis of medical data for 13 patients, proven for PLCH at Institute for Pulmonary diseases of Vojvodina in period of fifteen years. PLCH was found at 9 (69.3%) women and at 4 (30.7%) men, average age 34.7 years. Main clinical symptoms were cough (76.9%) and chest pain (61.5%). Out of 13 patients, 11 (84.6%) were smokers. In most cases PLCH histologically corresponded to the cellular phase of the disease (46.1%), proliferative phase was present at 5 (38.4%), and the fibrotic phase at 2 (15.5%) patients. Immunohistochemically, Langerhans’ cells were positive for presence of CD1a and S-100 antigens in all 13 of analyzed cases, while CD68 antigen was positive in 6 patients. In 6 patients (46.2%) there was disease regression, and at 7 (53.8%) patients the disease progressed despite the applied therapy. In our research, PHLC was more common in younger females, smokers with cough and chest pain. At most of the patients, histologically disease was in the cellular phase. Langerhans cells were positive to presence of CD1a and S100 antigens in all 13 patients. At more than half of the patients the disease progresses despite the applied therapy.

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC), which attempts to standardize reporting and cytological criteria for fine-needle aspiration of thyroid nodules and was first introduced in 2009, has been updated. Although much of the original TBSRTC remains the same, several “enhancements” have been introduced in the 2017 version based on new data and developments in the field. The 2017 revision reaffirms that every thyroid FNA report should begin with one of six diagnostic categories, the names of which remain unchanged since they were first introduced: nondiagnostic or unsatisfactory; benign; atypia of undetermined significance (AUS) or follicular lesion of undetermined significance (FLUS); follicular neoplasm or suspicious for a follicular neoplasm; suspicious for malignancy; and malignant. In the frst edition of TBSRTC, the implied risk of malignancy (MOP) for each diagnostic category was calculated and provided as a range based on a review of the literature at that time: 0–3% for benign, ~5–15% for atypia of undetermined signifcance (AUS) or follicular lesion of undetermined signifcance (FLUS), 15–30% for follicular neoplasm or suspicious for follicular neoplasm, 60–75% for suspicious for malignancy, and 97–99% for the malignant category. In the second edition, these ranges have been revised, especially for the so-called “indeterminate” categories, representing estimates calculated primarily from studies of large case cohorts and meta-analyses of ultrasound-guided thyroid FNA published after 2007. Notably, the new document reinterprets the previous version in one major way, and that is TBSRTC’s careful accommodation of the new noncancer category of noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) tumors, which prior to April 2016 were categorized as thyroid cancer. NIFTP tumors have nuclear changes on cytologic evaluation that are identical to other forms of thyroid cancer, but on close long-term clinical follow-up they do not appear to recur or metastasize, and therefore, they do not behave clinically like thyroid cancer. NIFTP tumors typically fall into categories 3, 4, or 5, and can only be diagnosed as “not cancer” after a full surgical excision is performed and the entire tumor specimen is examined under a microscope. There have also been a number of other enhancements with the 2017 update: • The option of molecular testing in the standard management of AUS/FLUS and FN/SFN has been included. • The definition and diagnostic criteria for FN/SFN has been modified: cases demonstrating mild nuclear changes associated with papillary thyroid carcinoma are now included. The definition and diagnostic criteria for the papillary thyroid carcinoma subset of the malignant category now suggest limiting use to cases with “classical” features of papillary thyroid carcinoma. TBSRTC is now the most common classification worldwide for the reporting of thyroid FNA specimens. In view of this, ABSTRACTS 92 MATERIA MEDICA • Vol. 34 • Issue 1, suplement 1 • april 2018. new suggestions will be useful for various aspects of thyroid FNA including nomenclature, differential diagnosis, the potential impact of NIFTP on the indeterminate diagnostic categories, utility of molecular and IHC markers, and clinical management.