Aim: To analyze age and sex distribution of the cardiac tumors, the most common clinical symptoms, POSTER SESIJA 70 MATERIA MEDICA • Vol. 34 • Issue 1, suplement 1 • april 2018. pathohistological types, tumor localization and compare the echocardiographic with the pathohistological size of the tumor. Introduction: The incidence of primary cardiac tumors are very rare and amounts to about 0.02%. Incidence of secondary cardiac tumors are significantly higher. Primary malignant cardiac tumors are very rare and represent to the rarest tumors in the human organism. Materials and Methods: The study covered 49 patients who were operated in the period from 2008 to 2017. Patients data are obtained from the history of the disease, the information system and pathohistological findings. Results: The average age of the patients is 53.9 years. The most common symptoms were light fatigue, heart palpitations, vertigo, dizziness, dyspnea, exhaustion, cough and stenocardia. The most commonly diagnosed are myxomas (67.3%), papillary fibroelastomas 28.6%, cavernous hemangiomas 4.1%, and metastatic tumors 2.04%. The most common tumor localization is in the left atrium 63.3%, aortic cusps 16.3%, right atrium 8.2%, mitral valve 8.2%, left ventricle 2.04% and interventricular septum 2.04%. The difference in mean echocardiographic tumor size and tumor size after surgical extirpation was not statistically significant (p = 0.706). Conclusion: Although, cardiac tumors are rare, they have a large clinical importance, primarily because of the potential for severe complications such as embolization of the arteries of the brain with the development of cerebral infarction and even the appearance of sudden death. However, timely diagnosis and surgical removal of tumors lead to patient curing in most cases.

Aim: Purpose of this report is to present metastasis of lymph nodes melanoma with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) as an example of collision tumor of an uncommon synchronic occurrence in the lymph node. Introduction: Synchronic, composite tumors are rare and their simultaneous and synchronic occurence within the same tissue/organ is even more rare. CLL/SLL is an indolent, clonal disease of mature B-lymphocytes which occurs mostly with adults. After the treatment with chemotherapeutic agents the occurence of the secondary malignancies (melanoma,squamous-cell carcinoma). Material and Methods: We present a 77 year old male who, after right sided nephrectomy caused by clear-cell carcinoma was diagnosed with CLL/SLL with bone marrow and lymph node infiltration. After three years and chemotherapy, skin changes were excised which histomorphologically resembles melanoma. After the immunotherapy for melanoma, the enlarged lymph nodes were extripated from the neck and histomorphologically and immunohistochemically treated. Results: Histomorphologically, a diffused infiltration of small B-lymphocytes was found in the lymph node, with round nuclei, condensed chromatin, inconspicuous nucleoli, scant cytoplasm unique immunophenotype: CD20 ,PAX-5 ,CD5 ,CD23 ,Cyclin D1-,CD3-. A part of lymph node was infiltrated by epitheloid cells with immunohistochemic profile: S-100 ,Melan A ,HMB-45 . Histomorphological and immunohistochemical CLL/SLL with melanoma infiltration as an example of a collision tumor was proved. Conclusion: Lymphoproliferative neoplasms including CLL/SLL represent an risk of synchronous, metachronous development of secondary malignancies including melanoma itself and they can uncommonly present themselves as synchronic collision tumors within the same organ.

Aim: We present the case of a patient aged 68 years who died of chronic heart failure caused by untreated cardiac sarcoidosis (CS). Introduction: Sarcoidosis is a multisystem disorder of unknown etiology, characterized by granulomatous infiltration and the development of noncaseating granulomas in many organ systems. Although the lungs, eyes, and skin are most commonly affected, virtually any body organ can be involved. Clinical evidence of CS is seen only in 5% of patients and the disease may present with tachyarrhythmias, conduction disturbance, heart failure, or sudden cardiac death. Case report: The patient was received in the hospital due to symptoms and signs of global cardiac decompensation with difficulties in the form of dyspnea, orthopnea, and edematous legs. Echocardiographic, cardiac cavities are very dilated with globally reduced systolic function, severe mitral regurgitation and ejection fraction about 20%. Very soon after receiving the patient is died. At autopsy, the heart was dilated, primarily the left ventricle. Histologically, the myocardium was infiltrated by numerous granulomas built of lymphocytes, epitheloid cells, and giant multicellular cells of the Langhans type. As a consequence of severe chronic heart failure, the lungs were edematous with both sides of massive plural effusions. The coronary arteries were non-significantly stenosed. Conclusion: Early diagnosis and treatment can prevent significant morbidity and mortality in patients with CS. It is very important that patients with CS in the early stage of the disease be treated with corticosteroids.

Aim: We present an illustrative autopsy case of thrombosed giant bilateral vertebral artery aneurysms. Introduction: A 61-year-old male died at Department of Infective disease with a clinical diagnosis for bilateral bronchopneumonia, cerebral aneurism, fibro muscular dysplasia, CVI, HTA, chronic CMP, cardiac arrest. Material and Methods: Standard autopsy technic with neuropathology brain dissection and standard procedure of paraffin embedded section routinely stained with HE was performed. Results: Gross examination of the brain at the autopsy showed saccular giant bilateral vertebral artery aneurysms that measured 58 mm on the right and 40 mm on the left artery. They were tumor-like and compressed the medulla and pons. Both were thrombosed. The right was ruptured with subacute subarachnoid bleeding. Sections of the cerebral vessels exhibited minimal atherosclerotic plaques, with mild stenosis (focally up to 10%) of the left internal carotid artery. We found mild dilatation on ventricles and minimal cortical atrophy of the brain. During the microscopic examination angiodysplasia with abnormally dilated blood vessels on visceral organs, predominantly on brain and heart was detected. The cause of death was central type of cardiopulmonary insufficiency with pulmonary edema. Conclusion: We presented an extremely rare case with bilateral giant vertebral aneurysms. Giant cerebral aneurysms are ones that measure >25 mm in greatest dimension and account for ~5% of all intracranial aneurysms. They occur in the 5th-7th decades and are more common in females. Vertebral artery aneurysms constitute 0.5 to 3% of intracranial aneurysms and 20% of posterior circulation aneurysms.

To present pathological processes of the TG with histological detection of granulomas, analysis of morphological forms of granulomas, and their diagnostic significance. This paper is based on literature review and insight into the archival materials of the Institute of Pathology and Forensic Medicine of the Military Medical Academy.The presence of granulomas in the thyroid gland (TG) includes specific pathological processes such as subacute thyroiditis (SAT) and palpation thyroiditis (PT). The clinical manifestations of the granulomas may be accompanied by symmetrical or asymmetrical enlargement and palpatory pain in the gland, which requires further clinical examination. Granulomas in the TG can be associated with various benign and malignant processes. There are two large groups of granulomas: foreign-body giant cell granulomas (FBG) and immune granulomas (IGR). FBG are histiocytic reactions to chemically inert, exogenous or endogenous materials. Etiologically, IGRs arise in the framework of infectious, autoimmune, toxic, drug-induced or pathological processes of unknown etiology. According to the presence of necrosis IGRs can be further divided as necrotizing or non-necrotizing type. TG granulomas of the infectious, autoimmune or inflammatory nature of the unknown etiology are extremely rare. 1. Granulomas in specific pathological processes of the TG Subacute (de Quervain’s) thyroiditis or granulomatous thyroiditis is an inflammatory process that is clinically presented as enlarged and painful TG. In most cases, the result is a complete recovery of the TG function. Permanent hypothyroidism is found in about 5% of patients. SAT is usually preceded by upper respiratory tract infection. The disease is etiologically related to viral infections, genetic predisposition and the use of immuno therapy. Macroscopically, TG is usually symmetrically enlarged, but there are also localized forms with nodular morphology, which imitate neoplastic lesions. The microscopic characteristic is the presence of multifocal and diffusely distributed folliculocentric granulomas. They are found in different phases and consist of epitheloid histiocytes, lymphocytes, plasma cells, neutrophils, and multinuclear giant cells (MGC). At the center of the granuloma, the colloid is reduced or absent. In later phases, fibrosis can develop perifollicularly. In terms of differential diagnosis (DDG), it is important to differentiate SAT from other granulomatous inflammations. Palpation thyroiditis (Multifocal granulomatous folliculitis) is the most common pathological process in TG with microscopic detection of granulomas. It is an incidental microscopic finding involving individual or minor follicular groups. Changes arise as a result of mechanical microtrauma after the palpation of the TG. Microscopic changes are characterized by damage to the follicles with interfollicular APSTRAKTI 73 MATERIA MEDICA • Vol. 34 • Issue 1, suplement 1 • april 2018. accumulation mainly of histiocytes in the presence of lymphocytes, plasma cells and MGCs. In the DDG of PT, the following conditions must be considered: SAT, primary and secondary microscopic foci of papillary microcarcinoma, C-cell hyperplasia, and focal forms of Langerhans histiocytosis. 2. Foreign-body giant cell granuloma is frequent incidental microscopic finding in TG. It arises as a reaction to the accumulation of endogenous substances in the areas of spontaneous or degenerations induces by fine-needle aspiration biopsy (FNAB). The most common forms of FBGs on endogenous material are cholesterol granulomas. These FBGs are composed of MGCs, foamy histiocytes, and hemosiderophages arranged around crystal deposits. Depending on how old the lesion is, there may be a focal necrosis, a different degree of fibrosis, extracellular deposits of hemosiderin, and other inflammatory cells. The presence of FBGs and histiocytic aggregates is not only important in the preoperative cytological diagnostics, but also in the post-operative pathohistological analysis of TG nodules. Large nuclei of histiocytes with hypochromasia, nuclear membrane irregularities and the presence of MGC can imitate the cytological features of papillary thyroid carcinoma (PTC). Exogenous biomaterials are rarely cause of FBGs in TG. After thyroidectomy, in cases of diagnosed TG malignancies, the presence of suture FBGs in thyroid bed imitates recurrence or the rest of malignancy and is the cause of repeated surgeries. 3. Necrotizing granulomas (NGR) in TG Granulomas with necrosis may be of infectious and noninfectious etiology. Tuberculosis is the most common cause of NGR in TG. Tuberculosis in TG can be presented as a solitary nodal lesion, diffuse microlesions, nodular goiter, and rarely as an abscess or a chronic skin sinus. As a infectious cause of NGR in TG, sporadically reported cases have been caused by histoplasmosis, coccidioidomycosis and nocardiosis. Rare non-infectious NGR in TG or in the TG bed, of autoimmune etiologies, have been described as part of Wegener’s granulomatosis and rheumatoid arthritis. Post-operative necrotizing granulomas also represent NGR of non-infectious cause. Microscopically, there is a morphology that matches post biopsy granulomas in other organs (prostate, urinary bladder). 4. Non-necrotizing granulomas (NNGR) in TG Sarcoidosis is a multi-systemic chronic granulomatous inflammation of unknown etiology. Thyroid is rarely affected by sarcoidosis. Macroscopically, the gland is diffusely or nodularly enlarged or reduced in volume. Interstitially localized NNGR represent a typical histological presentation. Sarcoidosis of TG should be distinguished from the sarcoid-like stromal reactions of PTC in the gland or regional lymph nodes. In these cases, it is necessary to clinically exclude the systemic disease. 5. Granulomas and histiocytic reactions in neoplastic processes of TG Apart from the described FBGs, PT and sarcoid-like reactions, in epithelial tumors of the TG histiocytic aggregates (not granulomas) may also be seen as secondary changes after FNAB. Interfollicular/ intraluminal presence of MGCs with or without the presence of histiocytes and granuloma-like morphology represents a characteristic finding in PTC. The cytological and histological detection of MGCs is one of the diagnostic criteria for PTC. Their presence in tumors may be due to a reaction to an altered colloid produced by PTC or as a non-specific immune response to due tumor cells. Conclusion: Granulomas in the TG are not rare. Knowing the morphology of granulomas, pathological processes and the circumstances in which they occur is significant in DDG of primary tumors of the TG, their recurrence and metastases in the cervical lymph nodes. The diagnosis of granulomatous inflammation in TG can be based on the histological characteristics of granulomas in correlation with clinical and laboratory findings.

Ova mala kliničko-patološka kategorija tumora se odlikuje nepredvidljivošću kliničkog toka i/ili ishoda bolesti, a tome u prilog često govore i patohistološka obeležja tumora koja pružaju samo neke odlike maligniteta, sugerišu mogući maligni potencijal ili pokazuju odlike između benignih i malignih proliferacija1. Boljim definisanjem dijagnostičkih kriterijuma danas su ovi tumori smanjeni na manje od 5% svih tumora u GI i HBP sistemima, a njihov maligni potencijal se često posredno izražava kao proliferativni, recidivni ili metastatski potencijal2,3. Najveći broj njih odnosi se na dobro diferentovane neuroendokrine tumore (NET), gastrointestinalne stromalne tumore (GIST) i mucinozne cistične neoplazije (MCN). Od epitelnih neoplazija nejasnog malignog potencijala u digestivnoj cevi se posebno izdvajaju mucinozne neoplazije apendiksa i cekuma (do 0,2% tumora GIT) često praćene rupturom i peritonealnim pseudomiksomom kao tzv. „diseminovana peritonealna mucinoza“4. One se odlikuju „cistadenomskom“ morfologijom, ponekad kompleksne acinusne i mikrocistične organizacije sa displastičnim epitelom i mucinoznom (pseudo)invazijom zida, ali bez invazivnosti epitelnih elemenata5. Slična histološka obeležja vide se u kod mucinoznih cističnih neoplazija (MCN) u biliopankreatičnom traktu i jetri, gde se displastične epitelne promene duktusa pankreasa (analogne pankreasnoj intraepitelnoj neoplaziji PanIN I-III), i bilijarnih duktusa (analogne bilijarnoj intraepitelnoj neoplaziji BilIN I-III) u perifernim zonama razgranavanja moraju jasno razlikovati od rane invazije, tj. od adenokarcinoma6. Kad su u pitanju adenomatozni polipi sa pseudoinvazijom u digestivnom traktu, oni se moraju razlikovati od pravih „malignih polipa“ tj. adenomatoznih polipa sa ranom invazijom koji pokazuju disekciju stromalnih elemenata mukoze i submukoze i izazivaju dezmoplastičnu reakciju. Pseudoinvazija se odlikuje odsustvom infiltrativnog tipa rasta, dezmoplazije, uočavanjem strome (lamine proprije) oko prolabiranih glandularnih struktura, hemoragijom, hemosiderofagijom, a nekada i invertnim rastom, bilo pulzionim ili limfovaskularnim, kao i stvaranjem limfoglandularnih kompleksa sa fokalnim limfoidnim agregatima7. Kada su u pitanju dobro diferentovani NET, danas se pored klasične i imunohistohemijske dijagnostike obavezno moraju odrediti i korelirati mitotski indeks (MI) izražen na 10 polja velikog mikroskopskog uveličanja, ali određen na najmanje 50 polja, kao i procentualni proliferativni Ki-67 indeks određen u području najveće aktivnosti na najmanje 500 ćelija. Na taj način određuje se stepen maligniteta NET koji po novoj klasifikaciji iz 2017. godine koji pored NET-G1 i NET-G2 podrazumeva i novouvedeni dobro diferentovani NET visokog stepena (NET-G3) za tumore sa MI preko 20 /10HPF i Ki-67 indeks preko 20%, ali koji se moraju razlikovati od slabo diferentovanih neuroendokrinih karcinoma (NEC) istih ili viših vrednosti ovih parametara8. Značajna je i grupa visceralnih mezenhimalnih tumora nejasnog malignog potencijala koji se pojavljuju u digestivnom sistemu, posebno za GIST kao najčešći od njih i koji čini oko 2% klinički značajnih tumora u abdomenu. Danas su jasno definisani AFIP kriterijumi malignog potencijala (Miettinen, 2005) i NIH kriterijumi metastaskog potencijala (Fletcher, 2002) koji čine i sastavni deo aktuelnih TNM klasifikacija. Oni uključuju obavezne podatke o preciznoj lokalizaciji i veličini tumora i mitotskom indeksu izraženom na 50 polja velikog mikroskopskog uveličanja9. Na osnovu toga se prepostavljaju stepeni rizika malignog toka bolesti i uključivanja adjuvantnih terapijskih protokola, dok je za lečenje metastatske i/ili neresektabilne bolesti neophodno određivanje mutacionog statusa KIT, PDGFRA, SDHA i SDHB gena. Takođe je značajno prepoznavanje i nalčin dijagnostike inflamatornog miofibroblastnog tumora (IMT) koji najčešće zahvata adolescente i mlade ženske odrasle osobe (75% intra-abdominalno i ponekad multinodularno), a histološki se odlikuje karakterističnom mešavinom inflamatornih (posebno limfoplazmocitnih i histiocitnih) i stromalnih (posebno miofibroblastnih) elemenata10. Karakteristična nuklearna imunoreaktivnost za ALK-1 protein se vidi samo u oko 50% slučajeva. Ovaj tip tumora ima nepredvidiv tok, ali se recidivi (29%) i metastaze (4%) češće javljaju kod epiteloidnih hipercelularnih i mitotski aktivnijih tumora sa pojavom nuklearne atipije stromalnih ćelija11. Hepato-biliopankreatični tumori nejasnog malignog potencijala osim pomenutih MCN podrazumevaju i intraduktalne papilarne mucinozne neoplazme (IPMN) sa teškom epitelnom displazijom (analogne BilIN III, PanIN III) ali bez pridružene mikroinvazije ili jasnih adenokarcinoma12. Takođe, hepatomi nejasnog malignog potencijala su hepatoidni tumori koji odgovaraju hepatocelularnim adenomima (HCA) s ati- 75 MATERIA MEDICA • Vol. 34 • Issue 1, suplement 1 • april 2018. pijom neoplastičnih ćelija i koji ne ispunjavaju sve ostale parametre maligniteta (elementi invazivnosti, trabekularna dezorganizacija i povećanje broja gredica, evidentna mitotska aktivnost) a po pravilu su “beta-katenin aktivišući tip” HCA koji se imunohistohemijski može dokazati i koji pokazuje visok stepen maligne transformacije13. Usled toga je neophodno ekstezivno uzorkovanje velikih HCA tumora da se ne bi previdela fokalna maligna alteracija. U jetri se retko može videti i epiteloidni hemangioendoteliom (EHE), nepredvidivog kliničkog toka, koji se često pogrešno interpretira kao (adeno)karcinom. Po pravilu se javlja kod osoba srednjeg životnog doba, kao multipla nodularna promena (80%) i javlja se s ekstrahepatičnim širenjem u 50% slučajeva. Neophodno je da se kod mladih jasno razlikuje od infantilnog hemangioendotelioma. Mikroskopski se odlikuje zonalnošću sa centralnom miksohondroidnom i sklerotičnom promenom u kojoj se vide dendritične tumorske ćelije, dok se periferno uočavaju delom obliterisani a delom prošireni sinusoidi sa papilarnim projekcijama atipičnog endotela14. Često se u tumorskim ćelijama vide intracitoplazmatske vakuole koje mogu sadržati eritrocite. Mora se razlikovati od dobro diferentovanog angiosarkoma visokom celularnošću i jačom atipijom, što je povezano i sa malignom alteracijom EHE. Pankreasna solidno-pseudopapilarna neoplazija se odlikuje češćim benignim kliničkim tokom nego recidivima i veoma retkim metastaziranjem. Opisala ju je Virginia Franz (1959) kao pedijatrijski benigni tumor, ali se danas izdvaja boljom mikroskopskom karakterizacijom kod adolescenata i mladih (10-45 god.). Obilno se javlja u distalnom pankreasu, promera od 3-15 cm kao jasno ograničen, lobuliran, hemoragičan tumor. Histološki ga odlikuju papilarnost, pseudorozete, holegranulomi i fokalna hijalinizacija15. Maligni potencijal i rizik metastaziranja se povezuju sa hipercelularnošću, atipijom i izraženijom mitotskom aktivnošću. 

Case 1: Clinical History -The patient was an 18-year-old woman with a history of primary amenorrhea. The physical examination revealed normal female external genitalia, moderate breast development, scarce pubic hair, and scant axillary hair. Pelvic examination revealed an absence of a uterus. The vagina ended in a blind pouch and measured 6cm in length. An abdominal ultrasonogram showed solid bilateral gonadal structures measuring 31x15mm right, and 30x 6mm left in the pelvic cavity without any evidence of a uterus. These findings were confirmed by MRI scan. Serum levels of estradiol and testosterone were 45.7pg/mL and 7.5nmol/L, respectively. FSH and LH levels were 8.46mlU/ml and 20.2mlU/ml. Cytogenetic analysis of peripheral blood lymphocytes revealed a 46,XY karyotype, with translocation t(13,14) inherited from her father. The molecular investigation confirmed active SRY with amplification of 6 nonpolymorphic loci on AZFa, AZFb, and AZFc regions on Y chromosome. Three months after her first referral the patient underwent bilateral prophylactic laparoscopic gonadectomy. The patient is being followed up regularly and she has no complaints after five years. Pathological Findings- Grossly, the right gonad was 4.3x1.8x1.8cm and the left gonad was 4.5x2.0x1.7cm. The right fallopian tube was 3.8cm long and 0.2cm in diameter, while the left one was 1.5cm long and 0.2cm in diameter. In addition, 4 cysts measuring 0.3- 1cm in diameter were found in the fat tissue on the surface of the left fallopian tube. The cut surface of the right gonad resembled testicular tissue showing two discrete, firm, well-demarcated, slightly bulging, homogenous, light grey-tan colored nodules, measuring 0.1 and 0.9cm in maximal dimension. Three similarly looking nodules were present in the left gonad measuring 0.4-0.5cm in diameter. In addition, a white whorled, firm, smooth muscle body fused to one pole of the gonad was found bilaterally measuring 1.2cm right, and 1.3cm left. Microscopically, both gonads were composed of varying proportions of small and solid, or less frequently larger, with early lumen formation seminiferous tubules lined by immature Sertoli cells, surrounded with fibrous, focally edematous stroma in which prominent Leydig cells were present. Rare tubules contained Sertoli cells with abundant cytoplasm filled with coarse, eosinophilic granules. The nodules were composed of solid immature tubules lined by cylindrical immature Sertoli cells separated by fibrous stroma containing fewer Leydig cells. Fallopian tubes were hypoplasic, while the cysts were lined by a single layer of cuboidal to columnar cells some of which had cilia. Thus, the clinical, laboratory, imaging, genetic and histological findings confirmed the diagnosis of complete androgen insensitivity syndrome with bilateral testicular hamartomas.Discussion Androgen insensitivity syndrome (AIS) is a disorder where there is resistance to androgen actions influencing both the morphogenesis and differentiation of androgen-responsive body structures. It is the most common type of male pseudohermaphroditism, characterized by an absence of androgen receptor activity due to a mutation at Xq11–q12 localization on the androgen receptor gene. the. In the largest series of 43 patients with the AIS published by Rutgers and Scully hamartomas were present in 63% of the cases, while Sertoli cell adenomas were reported in 23% and malignant tumors including two seminomas, one intratubular germ cell neoplasm with early stromal invasion and a malignant sex cord tumor in 9% of the cases. Case 2: Clinical History- The patient was a 17-year-old girl with primary amenorrhea. On external examination, she had an unambiguous female phenotype albeit with poor breast development. Her external genitalia had a normal appearance but internal examination showed a hypoplastic uterus. Ultrasonography failed to show follicular activity in the gonads. Her gonadotropins were high (FSH, 55.6mU/ml; LH, 18.3mU/ml) and estradiol was low (20.0pg/ml). Nonmosaic 46,XY karyotype was detected in patient’s leukocytes by cytogenetic analysis. Under the tentative clinical diagnosis of pure gonadal dysgenesis, a prophylactic bilateral laparoscopic gonadectomy with bilateral salpingectomy was performed. A biopsy specimens from the gonads were sent for cytogenetic analysis. The sequencing of the SRY gene of the proband revealed a C/G substitution at the first nucleotide of codon 133, leading to Arg/Gly replacement in the SRY protein. The mutation was also present in patient’s father, who is a phenotypically normal male. APSTRAKTI 77 MATERIA MEDICA • Vol. 34 • Issue 1, suplement 1 • april 2018. The patient is alive and well 12 years after the operation without any evidence of disease. Pathological Findings- Macroscopically, both fallopian tubes were 4cm long and 0.4cm in diameter, while the gonads were measuring 3x2.2x1.2cm the right, and 2.2x0.8x1cm the left. Upon dissection, both gonadal streaks had a similar, variegated appearance with multiple areas of microcalcification. The histological evaluation of the gonads confirmed a gonadoblastoma of 3cm in diameter in the right gonad and a predominantly “burnt-out” gonadoblastoma of 2.2cm in the left gonad with only a microscopic focus of recognizable gonadoblastoma less than 1mm in diameter. The tumors were composed of primordial germ cells intimately admixed with sex cord elements, which surrounded round spaces filled with eosinophilic basement membrane-like material. The atypical germ cells had abundant clear or pale, slightly granular cytoplasm and round vesicular nuclei with prominent nucleoli. The small, often fusiform sex cord element cells had uniform round or oval nuclei with indiscernible nucleoli and scant cytoplasm. The uninvolved gonadal tissue bilaterally had the morphology of a streak gonad composed largely of ovarian-type stroma, with extended calcification and small germinal inclusion cysts present, without any follicles. The fallopian tubes were infantile. Therefore, the histopathological findings confirmed the diagnosis of bilateral gonadoblastoma in streak gonads, FIGO Stage IB, in a patient with a XY gonadal dysgenesis (Swyer syndrome). Discussion: XY gonadal dysgenesis (GD) is a result of abnormal testis development in utero. Pure 46,XY GD should be considered when an adolescent presents as a phenotypic female with delayed puberty and primary amenorrhea. Rarely, they may present with a detectable abdominal or pelvic gonadoblastoma mass. When the presumptive diagnosis suggests GD, further criteria may strengthen the diagnosis, while ultimately, the most definitive diagnosis is through biopsy of the gonads. Bilateral streak gonads are seen in pure XY GD. The risk of otherwise undetected gonadoblastoma in XY GD patients is high, and prophylactic or therapeutic gonadectomy is therefore often indicated when XY GD is diagnosed. 

Aim: To present three cases and review literature of splenic myoid angioendothelioma (SMA) focusing on immunohistochemical features. Introduction: SMAs are very rare, mainly in middle-aged and elderly patients of both sexes and are characterized by a mixed proliferation of cord capillaries and myoid cells, distinguished from other splenic angioendotheliomas by additional myogenic/myofibroblast differentiation. Material and Methods: Three cases of SMA from the Department of Histopathology Registry of Clinical Centre of Serbia were detected during last 12 years (2006-2017) in one male and two female patients (42,5 ys average age). Histomorphological findings were revised by reviewing all serial HE sections, histochemical trichrome stains and immunohistochemical stainings for CD8, CD31, CD34, CD68, SMA, desmin and Ki-67. Results: All cases showed sharply demarcated non-encapsulated solitary tumors with diameters 42, 55 and 20 mm. Histologically there are dense network of capillary blood vessels intermingled with polygonal myoid stromal cells and at least focally expressed non-homogeneous cellularity of stromal and lymphoid cells with focal sclerosis. Neocapillaries show distinctive CD8- / CD31 / CD34 immunophenotype (differing them from splenic hamartomas) and characteristic mixture with myogenic elements (differing them from cord capillary hemangiomas): intense SMA (3/3), rare focal desmin (2/3) and focal CD68 (1/3) immunoexpression. Conclusion: SMA is underrecognized type of vascular neoplasia, which has a clinico-pathological differential diagnostic significance because it radiologically imitates splenic metastase. Cellular form of SMA must be distinguished from hamartoma, but also from hemangiopericytoma and well-differentiated angiosarcoma of the spleen

Aim: We present an unusual case of malignant gastrointestinal stromal tumor filling the entire abdominal cavity. Introduction: Gastrointestinal stromal tumors are the most common mesenchymal neoplasms of the gastrointestinal tract. Small tumors are generally benign, but large tumors disseminate to the liver, omentum and peritoneal cavity. They rarely occur in other abdominal organs. Material and Metods: The operative material consisted of segment of ileum where a tumor mass of 8 cm was found originating from the wall and fragments of small intestinal serosa and omentum where multiple nodular tumor mases were found. Representative samples were taken, and were paraffin embedded and stained routinely with Hematoxyllin-Eosin. Additionally immunohistochemical analyses were performed using the antibodies c-kit, CD34, Vimentin, CKAE1/AE3, Ki67 and others. Results: Microscopic analysis revealed a malignant gastrointestinal stromal tumor with a high mitotic rate of 58/50 HPF mitoses. However clinical reports stated that an additional large 12 cm tumor mass was found in the liver that was not removed. Conclusion: Gastrointestinal stromal tumors are the most common gastrointestinal mesenchymal neoplasms but presence of multiple tumor masses on various organs and sites is rare. Presence of multiple tumors in various organs brings about the issues of possibility of multiple primaries or the proper detection of the original tumor mass.

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.