Terapijski pristup seroznom karcinomu jajnika niskog gradusa

Low-grade serous ovarian cancer (LGSOC) has less aggressive behavior and a better clinical outcome than high-grade serous ovarian cancer (HGSOC). Considering that this malignancy is relatively chemoresistant, surgery is the keystone of treatment, with a strong recommendation for maximal cytoreduction. Women with stage IA-IB disease should undergo observation alone after primary cytoreductive surgery. In contrast, observation, chemotherapy, or endocrine therapy are possible options for those with stage IC-IIA disease. Patients with stage IIB-IV disease receive either chemotherapy with carboplatin and paclitaxel for six cycles followed by endocrine therapy, most commonly with aromatase inhibitors, or endocrine therapy alone until disease progression or unacceptable toxicity. Surgery, chemotherapy, and endocrine therapy are also used in patients with recurrent disease. Targeted agents, especially mitogen-activated protein kinase (MEK) inhibitors and cyclin-dependent kinase (CDK) inhibitors, are currently under evaluation in this clinical setting. Additional research on the genomics of LGSOC to better define the activating gene mutations involved in the carcinogenesis is strongly warranted to improve the prognosis with this malignancy.Niskogradusni serozni karcinom jajnika (LGSOC) manje je agresivan i ima bolji klinički ishod u usporedbi s visokogradusnim seroznim karcinomom jajnika (HGSOC). Kirurško liječenje s pokušajem maksimalne citoredukcije važno je i opravdano zbog relativne kemorezistencije ovog tumora. Stadije bolesti IA-IB trebalo bi klinički pratiti nakon primarne citoredukcije, dok su kliničko praćenje, kemoterapija ili hormonska terapija predložene mogućnosti za stadije bolesti IC-IIA. Bolesnice stadija IIB-IV liječe se kemoterapijom sastavljenom od karboplatina i paklitaksela tijekom 6 ciklusa koju slijedi hormonska terapija, najčešće inhibitorima aromataze, ili pak samom hormonskom terapijom do progresije bolesti ili neprihvatljive toksičnosti. Kirurško liječenje, kemoterapija i hormonska terapija također se koriste za bolesnice s povratom bolesti. U tijeku su klinička istraživanja ciljanom terapijom, posebno s inhibitorima mitogenom-aktiviranih proteinskih kinaza (MEK) i inhibitorima kinaza ovisnih o ciklinu (CDK). Dodatna istraživanja genomike LGSOC-a, u cilju boljeg definiranja aktivacije genskih mutacija uključenih u karcinogenezu, neophodna su radi poboljšanja prognoze ove zloćudne bolesti

Future Perspectives of Personalized Oncology

Based upon an individual’s molecular make-up, personalized molecular medicine provides information regarding the origin of disease, its treatment and progression, while personalized molecular pharmacology advises on drug prescription and patient response to it, thus ensuring drug effectiveness and preventing drug toxicity or lack of response. Interindividual differences in drug responses are mostly due to structural variation in parts of genome, e.g. in genes participating in drug metabolism, transport or targeting. However, a wide variety of diseases and accompanying health conditions, including patient’s therapy or drug response, also have epigenetic or epigenomic etiology. High priority for personalized oncologic research stems from inter/intraindividual tumor heterogeneity provoked by gradual acquisition of multiple random, or programmed mutations and rearrangements as well as epigenetic alterations or by stochastic fluctuations in cell components, all in tight feedback interaction with tumor’s environmental or therapy conditions. Natural selection subsequently shapes inter/intraindividual tumor heterogeneity by promoting clonal expansion of cells that have acquired advantageous mutations for tumor population. Hence, the main rationale of personalized molecular oncology should focus on treating disease by relying on relevant structure and state of patient’s whole molecular network (genome/transcriptome/RNome/proteome/metabolome/metabonome) in interaction with its unique environmental conditions, thus implying right therapy for the right patient at the right dose and time. The future of personalized oncology should therefore rely on the methods of systems biology applied in cytology and pathology in order to develop and utilize the efficient and effective diagnostic, prognostic and predictive biomarkers, consequently providing the molecular information on tumor origin, its potential for metastasis, adequate therapy, tumor specific therapy responsiveness, and the probability of its recurrence

Diagnosis of Visceral Leishmaniasis by Fine Needle Aspiration Cytology of an Isolated Cervical Lymph Node: Case Report

A 61-year-old woman presented with an isolated, painless, slightly enlarged right laterocervical lymph node without any other signs and symptoms of disease. Laboratory test including hematological and biochemical parameters were normal. A cervical ultrasonography demonstrated one lymph node (10 mm) on the right laterocervical side and one small reactive lymph node on the left laterocervical side. The fine needle aspiration (FNA) smears revealed a polymorphic population of cells composed of lymphocytes, histiocytes, epitheloid cells, plasma cell, tingible body macrophages and macrophages infiltrated with Leishmania amastigotes. Treatment was initiated with Stiboglukonat Na (Pentostam) and led to a full recovery

Mikrohematurija u rutinskoj citološkoj praksi: Iskustvo jednog centra

Hematurija predstavlja prisutnost eritrocita u urinu. Može biti makroskopska, golim okom vidljiva crvena ili smeđa boja urina, ili mikroskopska koja se može otkriti samo laboratorijskim pretragama. Mikrohematurija je definirana kao prisutnost najmanje 3 eritrocita po vidnom polju velikog povećanja pri mikroskopskom analiziranju uzorka urina. Klinički, hematurija može ukazivati na benigne ili maligne bolesti zbog čega zahtijeva odgovarajuću dijagnostičku obradu. U našoj bolnici značajan udio citoloških pregleda urina odnosi se na bolesnike upućene od strane liječnika obiteljske medicine s dijagnozom hematurije. Iako je glavni cilj citološke analize urina otkrivanje urotelijalnih karcinoma visokog stupnja, u velikom broju slučajeva citologija može utvrditi druge uzroke hematurije, bez potrebe za daljnjim dijagnostičkim postupcima. Naše istraživanje je obuhvatilo 304 uzorka urina primljenih na Odjelu za citologiju Kliničkog zavoda za patologiju, sudsku medicinu i citologiju Kliničkog bolničkog centra Split kroz period od jednog mjeseca. Najčešća postavljena dijagnoza od strane liječnika obiteljske medicine bila je mikrohaematurija (40,98%). Kod pacijenata s uputnog dijagnozom hematurije u 10,4% slučajeva nisu nađeni eritrociti u uzorcima urina kroz tri uzastopna dana. U 54,4% bolesnika dijagnosticirana je mikrohematurija, ali nije utvrđen osnovni uzrok. Atipične urotelijalne stanice i stanice urotelijalnog karcinoma visokog stupnja pronađene su u 9,6% bolesnika s mikrohematurijom. Cilj istraživanja bio je prikazati naše rezultate analize urina u rutinskoj citološkoj praksi u citološkom laboratoriju kod bolesnika s uputnom dijagnozom hematurije postavljenom od strane liječnika obiteljske medicine

CLINICAL RECOMMENDATIONS FOR DIAGNOSING, TREATMENT AND MONITORING OF PATIENTS WITH OVARIAN CANCER – CROATIAN ONCOLOGY SOCIETY AND CROATIAN SOCIETY FOR GYNECOLOGY AND OBSTETRICS AS CROATIAN MEDICAL ASSOCIATION UNITS AND CROATIAN SOCIETY OF GYNECOLOGICAL ONCOLOGY

Rak jajnika i jajovoda po učestalosti je peta zloćudna bolest žena u Hrvatskoj. Histološki je rak jajnika najčešće epitelnog podrijetla, i to seroznog podtipa. Rjeđi su različiti neepitelni malignomi jajnika, a posebnu skupinu čine epitelni karcinomi niskoga zloćudnog potencijala karakterizirani neinvazivnošću, klinički indolentnim tijekom i dobrom prognozom te primarni rak potrbušnice i rak jajovoda. Klinički su ovi zloćudni tumori u ranim stadijima razvoja uglavnom asimptomatski, zbog čega se najčešće dijagnosticiraju u kasnijim stadijima bolesti. Dijagnoza se potvrđuje patohistološkim nalazom, a iznimno citološkim nalazom nakon provedene dijagnostičke obrade. O liječenju odlučuje multidisciplinarni tim uzimajući u obzir dob, opće stanje i komorbiditete bolesnice, kao i obilježja samog tumora uključujući stadij bolesti, histološki tip i gradus tumora. Principi liječenja primarnog raka potrbušnice i jajovoda temelje se na principima liječenja epitelnog raka jajnika koji obuhvaćaju primjenu kirurških zahvata, kemoterapije, imunoterapije i hormonske terapije, kao i suportivno-simptomatskih mjera tijekom cijelog liječenja. Razlikuje se terapijski pristup rjeđim, neepitelnim histološkim tipovima tumora koji se češće dijagnosticiraju u ranim stadijima bolesti, imaju indolentniji tijek pa se kod ovih bolesnica češće primjenjuju poštedni kirurški zahvati s ciljem očuvanja plodnosti. U tekstu koji slijedi predstavljene su kliničke upute s ciljem standardizacije postupaka i kriterija postavljanja dijagnoze, liječenja te praćenja bolesnica s rakom jajnika, jajovoda i potrbušnice u Republici Hrvatskoj.Ovarian cancer together with fallopian tube represents the fifth most common female cancer in the Republic of Croatia. Epithelial ovarian cancer, serous subtype, encompasses most of malignant ovarian neoplasms. Less common are various non-epithelial ovarian malignancies. A special group consists of epithelial carcinomas of low malignant potential with clinically indolent flow, good prognosis and no invasion, and primary cancer of the peritoneum and fallopian tube cancer. Clinically, these malignant tumors are generally asymptomatic in early stages, and usually diagnosed in advanced stages. The diagnosis is confirmed by pathological examination, and occasionally, cytological findings after completing diagnostic procedures. Multidisciplinary team makes treatment decisions, taking into account age, general condition and comorbidities of the patient and characteristics of the tumor itself, including disease stage, histological type and grade of the tumor. The principles of treatment of primary peritoneal and fallopian tube cancer are based on the principles of treatment of epithelial ovarian cancer involving surgery, chemotherapy, immune and hormone therapy, and symptomatic-supportive care throughout the treatment. Less common histological types have a different treatment approach being more frequently diagnosed in the early stages of the disease, have more indolent flow, so in these patients conservative surgeries with the goal of preserving fertility are more often employed. The following text presents the clinical guidelines in order to standardize the procedures and criteria for the diagnosis, management, treatment and monitoring of patients with ovarian carcinoma, fallopian tube and primary peritoneal cancer in the Republic of Croatia

CLINICAL RECOMMENDATIONS FOR DIAGNOSING, TREATMENT AND MONITORING OF PATIENTS WITH ENDOMETRIAL CANCER – CROATIAN ONCOLOGY SOCIETY AND CROATIAN SOCIETY FOR GYNECOLOGY AND OBSTETRICS AS CROATIAN MEDICAL ASSOCIATION UNITS AND CROATIAN SOCIETY OF GYNECOLOGICAL ONCOLOGY

Rak trupa maternice javlja se u većini slučajeva u poslijemenopauzalnih žena, a najčešće se očituje ginekološkim krvarenjem. Nakon raka jajnika i vrata maternice treći je uzrok smrti žena od raka spolnog sustava. Dijagnoza se postavlja patohistološkim pregledom kiretmana ili bioptata, a definitivni stadij bolesti utvrđuje se analizom uzoraka dobivenih histerektomijom i obostranom salpingoovariektomijom sa zdjeličnom i paraaortalnom limfadenektomijom. U tekstu koji slijedi sadržane su kliničke upute s ciljem standardizacije postupaka i kriterija postavljanja dijagnoze, liječenja i praćenja bolesnica s rakom trupa maternice u Republici Hrvatskoj.Uterine cancer occurs mainly in postmenopausal women, usually as vaginal bleeding. Following ovarian and cervical cancer it is the third most common cause of female reproductive system cancer death. Diagnosis is set by analyzing samples obtained via hysterectomy with salpingo-oophorectomy and pelvic / paraaortal lymphadenectomy. The following text presents the clinical guidelines in order to standardize the procedures and criteria for the diagnosis, treatment and monitoring of patients with uterine cancer in the Republic of Croatia

p53 protein, MAPK and topoisomerase II α in serous ovarian carcinomas

Cilj istraživanja. Cilj ovog istraživanja bio je utvrditi razinu imunohistokemijske ispoljenosti p53 proteina, MAPK i topoizomeraze IIα u seroznim karcinomima jajnika niskog i visokog gradusa, te utvrditi njihovu povezanost sa kliničko-patološkim prognostičkim pokazateljima, dužinom slobodnog intervala bez bolesti i ukupnim preživljenjem te odgovorom na kemoterapiju. Materijali i metode. U istraživanje je uključena 81 bolesnica sa seroznim karcinomom jajnika, operirana u razdoblju od 1995. do 2005. godine. Uzorci tumora bojani su imunohistokemijski primjenom protutijela za p53, MAPK i topo IIα. Učinjena je i KRAS/BRAF mutacijska analiza na uzorcima 73 tumora. Rezultati. Deset bolesnica (12.3%) dijagnosticirano je u ranom kliničkom stadiju bolesti. Od 81 seroznog karcinoma, 13.6% morfološki je odgovaralo karcinomu niskog gradusa (tip I tumori), a 86.4% karcinomu visokog gradusa (tip II tumori). Serozni karcinomi niskog i visokog gradusa statistički se značajno razlikuju prema imunohistokemijskom izražaju p53 proteina (P=<0.001), MAPK (P=0.003), i topoizomeraze IIα (P=0.001). Pozitivna imunohistokemijska reakcija na p53 protein nađena u 85.7% karcinoma visokog gradusa i u niti jednom karcinomu niskog gradusa. Mutacija KRAS gena nađena je u 54.5% karcinoma niskog gradusa i u samo 13.8% karcinoma visokog gradusa (P=0.006). BRAF mutacija nije nađena ni u jednom uzorku. Pozitivan MAPK izražaj bio je prisutan u dva od pet uzoraka niskog gradusa i u 11 od 54 uzorka visokog gradusa koji su bili negativni na KRAS mutaciju, što govori u prilog činjenici da aktivacija MAPK signalnog puta nije isključivo vezana uz KRAS mutaciju. Kod sedam (11.7%) uzoraka karcinoma koji su morfološki odgovarali karcinomima visokog gradusa, zabilježili smo i mutaciju KRAS gena koja je obilježje puta karcinogeneze tip I i pozitivan imunohistokemijski izražaj p53 proteina, obilježje puta karcinogeneze tip II. U pet od sedam ovih uzoraka nađeni su i morfološki dijelovi koji odgovaraju seroznom borderline tumoru i/ili seroznom karcinomu niskog gradusa. Prema rezultatima uninominalne analize, klinički stadij bolesti (P=0.007) i pozitivan imunohistokemijski izražaj MAPK proteina (P=0.027) vezani su uz duži slobodni interval bez bolesti (DSF), dok su dob bolesnica iznad 60 godina (P=0.044), veličina ostatnog tumora (P<0.001), nalaz vaskularne invazije (P=0.002), viši gradus tumora (P=0.025) te klinički stadij III-IV (P=0.010) povezani s kraćim ukupnim preživljenjem (OS). Prema rezultatima multinominalne analize, ostatni tumor (P<0.001) i vaskularna invazija (P=0.084) nezavisni su predskazatelji kraćeg preživljenja bolesnica sa seroznim karcinomom jajnika, dok su se klinički stadij bolesti (P=0.004) i pozitivan imunohistokemijski izražaj MAPK proteina (P=0.077) potvrdili kao nezavisni predskazatelji slobodnog intervala bez povrata bolesti. Imunohistokemijski izražaj p53 proteina, MAPK i topoizomeraze IIα nije povezan s odgovorom na kemoterapiju temeljenu na platini. Bolesnice sa MAPK negativnim karcinomom i potpunim odgovorom na prvu liniju kemoterapije imaju kraće vrijeme do pojave recidiva bolesti (P=0.060). Zaključak: Iako je istraživanje ograničeno malim brojem seroznih karcinoma niskog gradusa, dokazali smo da se karcinomi niskog i visokog gradusa značajno razlikuju prema imunohistokemijskom izražaju p53 proteina, MAPK, i topoizomeraze IIα te se imunohistokemijsko bojanje na navedene biljege može koristiti u razdvajanju morfološki dvojbenih uzoraka. Postoje morfološka, imunohistokemijska i molekularna prekapanja između ove dvije skupine karcinoma, koja upućuju na mogućnost transformacije karcinoma niskog gradusa u karcinome visokog gradusa, vjerojatno potaknuta mutacijom p53 gena. Razdvajanje seroznih karcinoma jajnika u dvije grupe u budućnosti bi trebalo utjecati na potencijalne metode prevencije i probira, uz različit pristup liječenju bolesnica sa seroznim karcinoma jajnika niskog i visokog gradusa.Background: The aim of this study was to assess the immunohistochemical expression of p53, MAPK and topoisomerase II alpha in ovarian serous carcinomas (OSCs), and their relation with clinicopathological prognostic factors, disease free and overall survival and chemotherapy response. Methods: The study included 81 patients with OSCs who underwent surgery between 1995 and 2005. Formalin fixed paraffin embedded tumour sections were reviewed and examined immunohistochemically using antibodies against p53, MAPK and topoII alpha. KRAS and BRAF mutational analysis was performed on 73 available microdissected samples. Results: Ten patients (12.3%) were diagnosed in early stage of disease. Of 81 cases of OSCs, 13.6% were of low-grade (Type I) and 86.4% were of high-grade (Type II) morphology. We have found statistically significant differences in the immunohistochemical expression of p53 (P=<0.001), MAPK (P=0.003) and topo IIα (P=0.001) between these two groups. In the high-grade group, 85.7% of cases showed positive p53 immunoexpression, but none of the low-grade samples was p53 positive. KRAS mutation was found in 54.5% of low-grade and 13.8% of high-grade OSCs (P=0.006). None of the samples had BRAF mutation. MAPK positivity showed two of five low-grade carcinomas and 11 of 54 high-grade carcinomas with wild-type KRAS, suggesting that activation of MAPK pathway is not ultimately related to KRAS mutation. We identified seven (11.7%) high-grade samples that showed both KRAS mutation, which is a hallmark of Type I pathway of carcinogenesis, and p53 immunopositivity, which is a hallmark of Type II pathway. In five of seven high-grade samples we have found elements of serous borderline tumour and/or low-grade serous carcinoma. On uninominal analysis, early FIGO stage (P=0.007) and positive MAPK immunoexpression (P=0.027) were significantly associated with longer disease free survival (DFS), while age over 60 (P=0.044), residual disease (P<0.001), vascular invasion (P=0.002), high-grade morphology (P=0.025) and FIGO stage III-IV (P=0.010) were related to significantly shorter overall survival (OS). Multinominal analysis revealed that residual disease (P<0.001) and vascular invasion (P=0.084) were independent predictors of shorter survival, while early FIGO stage (P=0.004) and positive MAPK immunoexpression (P=0.077) were independent predictors of disease free survival. Positive p53, MAPK and topo IIα immunoexpression was not associated with response to platinum-based chemotherapy. Patients with MAPK negative carcinomas and complete response to first-line chemotherapy have significantly shorter disease free interval (P=0.060). Conclusions: Although this study is limited by its humble number of low-grade samples, we have found statistically significant differences in the immunohistochemical expression of p53, MAPK and topo IIα between low-grade and high-grade carcinomas, therefore immunohistochemical staining with these markers could be a useful additional tool in distinguishing morphologically questionable samples. There are morphological, immunohistochemical and molecular overlaps between these two groups, which indicate the possibility of transformation of low-grade into high-grade carcinomas, probably triggered by p53 gene mutation. Separation of ovarian serous carcinomas in two groups in the future should influence the potential methods of prevention and screening, with a different approach to treatment of patients with low-grade and high-grade serous carcinomas

p53 protein, MAPK and topoisomerase II α in serous ovarian carcinomas

Cilj istraživanja. Cilj ovog istraživanja bio je utvrditi razinu imunohistokemijske ispoljenosti p53 proteina, MAPK i topoizomeraze IIα u seroznim karcinomima jajnika niskog i visokog gradusa, te utvrditi njihovu povezanost sa kliničko-patološkim prognostičkim pokazateljima, dužinom slobodnog intervala bez bolesti i ukupnim preživljenjem te odgovorom na kemoterapiju. Materijali i metode. U istraživanje je uključena 81 bolesnica sa seroznim karcinomom jajnika, operirana u razdoblju od 1995. do 2005. godine. Uzorci tumora bojani su imunohistokemijski primjenom protutijela za p53, MAPK i topo IIα. Učinjena je i KRAS/BRAF mutacijska analiza na uzorcima 73 tumora. Rezultati. Deset bolesnica (12.3%) dijagnosticirano je u ranom kliničkom stadiju bolesti. Od 81 seroznog karcinoma, 13.6% morfološki je odgovaralo karcinomu niskog gradusa (tip I tumori), a 86.4% karcinomu visokog gradusa (tip II tumori). Serozni karcinomi niskog i visokog gradusa statistički se značajno razlikuju prema imunohistokemijskom izražaju p53 proteina (P=<0.001), MAPK (P=0.003), i topoizomeraze IIα (P=0.001). Pozitivna imunohistokemijska reakcija na p53 protein nađena u 85.7% karcinoma visokog gradusa i u niti jednom karcinomu niskog gradusa. Mutacija KRAS gena nađena je u 54.5% karcinoma niskog gradusa i u samo 13.8% karcinoma visokog gradusa (P=0.006). BRAF mutacija nije nađena ni u jednom uzorku. Pozitivan MAPK izražaj bio je prisutan u dva od pet uzoraka niskog gradusa i u 11 od 54 uzorka visokog gradusa koji su bili negativni na KRAS mutaciju, što govori u prilog činjenici da aktivacija MAPK signalnog puta nije isključivo vezana uz KRAS mutaciju. Kod sedam (11.7%) uzoraka karcinoma koji su morfološki odgovarali karcinomima visokog gradusa, zabilježili smo i mutaciju KRAS gena koja je obilježje puta karcinogeneze tip I i pozitivan imunohistokemijski izražaj p53 proteina, obilježje puta karcinogeneze tip II. U pet od sedam ovih uzoraka nađeni su i morfološki dijelovi koji odgovaraju seroznom borderline tumoru i/ili seroznom karcinomu niskog gradusa. Prema rezultatima uninominalne analize, klinički stadij bolesti (P=0.007) i pozitivan imunohistokemijski izražaj MAPK proteina (P=0.027) vezani su uz duži slobodni interval bez bolesti (DSF), dok su dob bolesnica iznad 60 godina (P=0.044), veličina ostatnog tumora (P<0.001), nalaz vaskularne invazije (P=0.002), viši gradus tumora (P=0.025) te klinički stadij III-IV (P=0.010) povezani s kraćim ukupnim preživljenjem (OS). Prema rezultatima multinominalne analize, ostatni tumor (P<0.001) i vaskularna invazija (P=0.084) nezavisni su predskazatelji kraćeg preživljenja bolesnica sa seroznim karcinomom jajnika, dok su se klinički stadij bolesti (P=0.004) i pozitivan imunohistokemijski izražaj MAPK proteina (P=0.077) potvrdili kao nezavisni predskazatelji slobodnog intervala bez povrata bolesti. Imunohistokemijski izražaj p53 proteina, MAPK i topoizomeraze IIα nije povezan s odgovorom na kemoterapiju temeljenu na platini. Bolesnice sa MAPK negativnim karcinomom i potpunim odgovorom na prvu liniju kemoterapije imaju kraće vrijeme do pojave recidiva bolesti (P=0.060). Zaključak: Iako je istraživanje ograničeno malim brojem seroznih karcinoma niskog gradusa, dokazali smo da se karcinomi niskog i visokog gradusa značajno razlikuju prema imunohistokemijskom izražaju p53 proteina, MAPK, i topoizomeraze IIα te se imunohistokemijsko bojanje na navedene biljege može koristiti u razdvajanju morfološki dvojbenih uzoraka. Postoje morfološka, imunohistokemijska i molekularna prekapanja između ove dvije skupine karcinoma, koja upućuju na mogućnost transformacije karcinoma niskog gradusa u karcinome visokog gradusa, vjerojatno potaknuta mutacijom p53 gena. Razdvajanje seroznih karcinoma jajnika u dvije grupe u budućnosti bi trebalo utjecati na potencijalne metode prevencije i probira, uz različit pristup liječenju bolesnica sa seroznim karcinoma jajnika niskog i visokog gradusa.Background: The aim of this study was to assess the immunohistochemical expression of p53, MAPK and topoisomerase II alpha in ovarian serous carcinomas (OSCs), and their relation with clinicopathological prognostic factors, disease free and overall survival and chemotherapy response. Methods: The study included 81 patients with OSCs who underwent surgery between 1995 and 2005. Formalin fixed paraffin embedded tumour sections were reviewed and examined immunohistochemically using antibodies against p53, MAPK and topoII alpha. KRAS and BRAF mutational analysis was performed on 73 available microdissected samples. Results: Ten patients (12.3%) were diagnosed in early stage of disease. Of 81 cases of OSCs, 13.6% were of low-grade (Type I) and 86.4% were of high-grade (Type II) morphology. We have found statistically significant differences in the immunohistochemical expression of p53 (P=<0.001), MAPK (P=0.003) and topo IIα (P=0.001) between these two groups. In the high-grade group, 85.7% of cases showed positive p53 immunoexpression, but none of the low-grade samples was p53 positive. KRAS mutation was found in 54.5% of low-grade and 13.8% of high-grade OSCs (P=0.006). None of the samples had BRAF mutation. MAPK positivity showed two of five low-grade carcinomas and 11 of 54 high-grade carcinomas with wild-type KRAS, suggesting that activation of MAPK pathway is not ultimately related to KRAS mutation. We identified seven (11.7%) high-grade samples that showed both KRAS mutation, which is a hallmark of Type I pathway of carcinogenesis, and p53 immunopositivity, which is a hallmark of Type II pathway. In five of seven high-grade samples we have found elements of serous borderline tumour and/or low-grade serous carcinoma. On uninominal analysis, early FIGO stage (P=0.007) and positive MAPK immunoexpression (P=0.027) were significantly associated with longer disease free survival (DFS), while age over 60 (P=0.044), residual disease (P<0.001), vascular invasion (P=0.002), high-grade morphology (P=0.025) and FIGO stage III-IV (P=0.010) were related to significantly shorter overall survival (OS). Multinominal analysis revealed that residual disease (P<0.001) and vascular invasion (P=0.084) were independent predictors of shorter survival, while early FIGO stage (P=0.004) and positive MAPK immunoexpression (P=0.077) were independent predictors of disease free survival. Positive p53, MAPK and topo IIα immunoexpression was not associated with response to platinum-based chemotherapy. Patients with MAPK negative carcinomas and complete response to first-line chemotherapy have significantly shorter disease free interval (P=0.060). Conclusions: Although this study is limited by its humble number of low-grade samples, we have found statistically significant differences in the immunohistochemical expression of p53, MAPK and topo IIα between low-grade and high-grade carcinomas, therefore immunohistochemical staining with these markers could be a useful additional tool in distinguishing morphologically questionable samples. There are morphological, immunohistochemical and molecular overlaps between these two groups, which indicate the possibility of transformation of low-grade into high-grade carcinomas, probably triggered by p53 gene mutation. Separation of ovarian serous carcinomas in two groups in the future should influence the potential methods of prevention and screening, with a different approach to treatment of patients with low-grade and high-grade serous carcinomas