Multiple sarcomatoid carcinomas in the small intestine with perforation: A case report and literature review.

RATIONALE: Sarcomatoid carcinoma of the small intestine is an exceedingly rare and aggressive malignancy, often diagnosed at advanced stages with a poor prognosis. This study documents a detailed case of sarcomatoid carcinoma of the small intestine, highlighting the diagnostic challenges and treatment approaches, underscored by a comprehensive review of related literature. Given the rarity of this condition, our report aims to enrich the existing diagnostic and treatment frameworks for this malignancy, emphasizing the necessity for early detection and intervention strategies. By presenting this case in conjunction with a literature review, we seek to shed light on the elusive nature of sarcomatoid carcinoma in the small intestine and propose avenues for improving patient outcomes. PATIENT CONCERNS: Case presentation A 61-year-old male patient initially presented with recurrent abdominal pain and gastrointestinal symptoms. Initial abdominal computed tomography (CT) scans and gastrointestinal endoscopy revealed only inflammatory and hyperplastic changes in the duodenum and jejunum, with a diagnosis of intestinal obstruction. Two years later, due to gastrointestinal perforation, the patient was hospitalized again. DIAGNOSES: CT scans and other examinations revealed small intestinal lesions. Four small intestinal lesions were surgically removed, and pathology and immunohistochemistry confirmed sarcomatoid carcinoma of the small intestine. A short time later, enhanced CT scans revealed metastatic lesions in the hepatic portal and adrenal glands. INTERVENTIONS: After surgery, the gastrointestinal function gradually recovered, and the patient was discharged from the hospital on a semiliquid diet. No further treatment such as radiotherapy or chemotherapy was administered postoperatively. OUTCOMES: Five months after the surgery, the patient died due to brain metastasis. LESSONS: The study outcomes reveal the aggressive nature of sarcomatoid carcinoma of the small intestine, characterized by rapid progression and poor prognosis despite surgical interventions. The patient condition rapidly deteriorated, leading to metastasis and death within 5 months postsurgery. These findings underscore the critical need for early detection and possibly innovative treatment approaches to improve survival rates. This case also highlights the potential for gastrointestinal sarcomatoid carcinoma to metastasize to distant organs, including the brain, suggesting a propensity for hematogenous spread.

Acinic cell Carcinoma with high-grade Squamoglandular and Chondrosarcomatous Transformation Mimicking 'Carcinosarcoma ex-pleomorphic Adenoma': A Wrinkle in the Proposed Nomenclature Revision for Sarcomatoid Salivary Gland Neoplasms.

While acinic cell carcinoma (AciCC) can undergo high-grade transformation (HGT) to high-grade adenocarcinoma or poorly differentiated carcinoma, other morphologies such as spindle cell/sarcomatoid carcinoma are rare and not well-characterized. We herein report a novel case of AciCC with squamoglandular and chondrosarcomatous HGT mimicking a so-called 'carcinosarcoma ex-pleomorphic adenoma'. The patient is an 81-year-old male with a two-month history of neck swelling and referred otalgia who presented with a left parapharyngeal space mass extending into retropharyngeal space and pterygoid muscles. On resection, the tumor showed considerable morphologic diversity with high-grade serous and mucous acinar components as well as cribriform to solid apocrine-like components with comedonecrosis and squamous differentiation, all of which were embedded in a chondromyxoid background ranging from paucicellular and bland to a high-grade chondrosarcoma/pleomorphic sarcoma-like appearance. Only a minor conventional AciCC component was noted. Immunostains were negative for AR and only focally positive for GCDFP-15 arguing against a true apocrine phenotype, while PLAG1 and HMGA2 were negative arguing against an antecedent pleomorphic adenoma. On the other hand, SOX-10, DOG-1 and PAS after diastase highlighted serous acinar differentiation, and mucicarmine, and NKX3.1 highlighted mucous acinar differentiation. NR4A3 immunohistochemical staining and NR4A3 fluorescence in situ hybridization were positive in the carcinomatous and sarcomatoid components while sequencing analysis of both components revealed identical alterations involving TP53, PIK3CB, ARID1A, and STK11. This unique case warrants caution in designating all salivary sarcomatoid carcinomas with heterologous elements as part of the 'carcinoma ex-pleomorphic adenoma' family.

Sarcoma of the uterine cervix: experience of a single center.

OBJECTIVES: To investigate the clinicopathological characteristics and prognosis of patients with primary sarcoma of the uterine cervix. METHODS: We identified all patients with primary cervical sarcomas treated at our institution from 2002 to 2020 and analyzed the clinicopathological characteristics and prognosis. RESULTS: 34 patients were identified, 7 (20.6%) patients had leiomyosarcoma, 6 (17.6%) had carcinosarcoma, 5 (14.7%) had Ewing sarcoma, 4 (11.8%) had rhabdomyosarcoma, 4 (11.8%) had undifferentiated sarcoma, 2 (5.9%) had adenosarcoma, 2 (5.9%) had endometrial stromal sarcoma, 1 (2.9%) had dermatofibrosarcoma protuberans, 1 (2.9%) had alveolar soft tissue sarcoma and 2 (5.9%) had sarcoma not otherwise specified. The median age of the whole patients was 43.5 years (range, 13-63). The median age of patients with Ewing sarcoma or rhabdomyosarcoma was 22 years (range, 13-39) and 17 years (range, 13-36 years), respectively. The distribution by stage was: stage I in 21 (61.8%) patients, stage II in 4 (11.8%), stage III in 6 (17.6%) and stage IV in 3 (8.8%). Overall, 30 patients (88.2%) received surgical treatment. The median follow-up was 33.3 months (range 3.6-187.3 months). 11 patients died within 2 years after diagnosis, most of them were patients with carcinosarcoma or undifferentiated sarcoma (45.5%, 5/11). In the entire cohort, 2- and 5-year OS were 67.2% and 56.9%, respectively. 5-year OS was 25.0% for undifferentiated sarcoma, 50.0% for rhabdomyosarcoma, 50.0% for carcinosarcoma, 53.3% for Ewing sarcoma, 57.1% for leiomyosarcoma. CONCLUSION: Cervical sarcomas are rare neoplasms with multiple histological subtypes and follow an aggressive course. Prognosis may be associated with tumor histology and stage.

Case report: Pathological complete response induced by immunochemotherapy in a case of Pulmonary Sarcomatoid Carcinoma staged IIIA-N2.

Pulmonary sarcomatoid carcinoma (PSC) represents a rare and highly aggressive variant of lung cancer, characterized by its recalcitrance to conventional therapeutic modalities and the attendant dismal prognosis it confers. Recent breakthroughs in immunotherapy have presented novel prospects for PSC patients; nevertheless, the utility of neoadjuvant/conversional immunotherapy in the context of PSC remains ambiguous. In this report, we present a middle-aged male presenting with Stage III PSC, notable for its high expression of the programmed death-ligand 1 (PD-L1), initially deemed as non-resectable for sizeable tumor mass and multiple lymph nodes metastases. The patient underwent a transformation to a resectable state after a regimen of three cycles of platinum-based chemotherapy plus immunotherapy. Following definitive surgical resection, the individual realized a pathological complete response (pCR), culminating in a significant prolongation of event-free survival (EFS). This case underscores the viability of employing immunochemotherapy as a neoadjuvant/conversional strategy for chosen cases of PSC.

Neoadjuvant Chemotherapy in Locally Advanced Sinonasal Teratocarcinosarcoma a Rare Malignancy: An Audit From an Academic Tertiary Care Centre in India.

AIMS: Sinonasal teratocarcinosarcomas (SNTCS) are rare sinonasal malignancies, the incidence of which is less than 1% of all tumors. There is limited data available on SNTCS's, often as case reports and small case series. The management of SNTCS is complicated because of its location, locally aggressive biology, difficulty in achieving complete resection, and limited data on chemotherapy in these malignancies. This audit was performed to understand the role of neoadjuvant chemotherapy (NACT) in SNTCS's, its ability to downstage the disease, achieve complete resection, and impact on long-term survival outcomes. METHODS: This was a retrospective analysis of a prospectively maintained database approved by the Institutional Ethics Committee (IEC). The baseline characteristics, the extent of tumor, Kadish stage, NACT regimen, and adverse events were extracted from the Electronic Medical Records and the patient's case file. Patients with baseline extensive/inoperable disease were referred for NACT from the multidisciplinary joint clinic followed by response assessment (RECIST v1.1). Patients underwent skull-base surgery if respectable post-completion of NACT, however, if deemed unresectable were treated with non-surgical modalities or palliative therapies. RESULTS: The data of 27 patients were evaluated from the year 2015-2022. The median age was 42 years (IQR:30-56) and 85.2% (n = 23) were males. The ECOG-PS was 0-1 in 88.8% (n = 24) patients. All 27 patients received NACT in view of extensive disease at presentation. 74.1% (n = 20) patients received Cisplatin-Etoposide and 25.9% (n = 7) received other chemotherapy regimens. The median number of chemotherapy cycles was 2(IQR:2-3). 96.3% patients (n = 26) completed the planned NACT cycles. 70.4% (n = 19) patients achieved a partial response in post-NACT imaging. 77.8% (n = 18) underwent surgery, 18.5% (n = 5) received CTRT, and 7.4% (n = 2) received definitive-RT alone. The median PFS and OS of the cohort was 19months (95%CI:12.0-25.6) and 23months (95%CI:5.94-40.06) respectively. CONCLUSION: NACT is safe, feasible, and effective with significant response rates, leading to effective downstaging, resectability and improved survival in patients with locally advanced SNTCS's.

[Primary hepatic sarcomatoid carcinoma, an unusual case]. / Carcinoma sarcomatoide hepático primario metastásico, una neoplasia infrecuente.

Primary hepatic sarcomatoid carcinoma is a very aggressive tumor, representing 0.4-0.7% of all primary hepatic neoplasms. The disease is associated with liver disease due to hepatotropic viruses and is more prevalent in Asians. Histology shows sarcomatous and carcinoma components. It does not have pathognomonic clinical or imaging characteristics and its diagnosis is based on the pathological and immunohistochemistry findings. Surgery could prolong survival in localized stages. We report the case of a 72-year-old Korean patient with a history of chronic liver disease due to B virus, who was diagnosed with primary hepatic sarcomatoid carcinoma with bone and lymph node metastases.

El carcinoma sarcomatoide primario hepático es un tumor agresivo que representa el 0.4-0.7% de todas las neoplasias primarias hepáticas. Se asocia a hepatopatía por virus hepatotropos, es más prevalente en la población asiática y en su histología se evidencian componentes de carcinoma y sarcoma. No posee características clínicas ni imagenológicas patognomónicas y su diagnóstico se realiza en base a los hallazgos de la anatomía patológica e inmunohistoquímica. La cirugía en estadio localizado representa la única modalidad terapéutica con impacto en la sobrevida. Reportamos el caso de una paciente de 72 años, coreana, con antecedentes de hepatopatía crónica por virus B, a quien se le diagnosticó un carcinoma sarcomatoide hepático primario con metástasis ósea y ganglionares.

Risk of endometrial cancer after RRSO in BRCA 1/2 carriers: a multicentre cohort study / Riesgo de cáncer de endometrio después de RRSO en portadoras de BRCA 1/2: un estudio de cohorte multicéntrico

Objective: To know the risk of endometrial cancer (EC) in a population of women with BRCA 1/2 pathogenic or likely pathogenic variants after risk-reducing salpingo-oophorectomy (RRSO). Methods: The study cohort included data from 857 women with BRCA mutations who underwent RRSO visited four hospitals in Catalonia, Spain, from January 1, 1999 to April 30, 2019. Standardized incidence ratio (SIR) of EC was calculated in these patients using data from a regional population-based cancer registry. Results: After RRSO, eight cases of EC were identified. Four in BRCA 1 carriers and four in BRCA2 carriers. The expected number of cases of EC was 3.67 cases, with a SIR of 2.18 and a 95% CI (0.93–3.95). Conclusions: In our cohort, the risk of EC in BRCA1/2 carriers after RRSO is not greater than expected. Hysterectomy is not routinely recommended for these patients.(AU)

Is Primary Poorly Differentiated Sarcomatoid Malignancy of the Parotid Gland Sarcomatoid Undifferentiated/Dedifferentiated Melanoma? Report of Three Unusual Cases Diagnosed by Fine-Needle Aspiration Combined with Histological, Immunohistochemical, and Molecular Analyses.

INTRODUCTION: Poorly differentiated primary sarcomatoid parotid malignancies are extremely rare. These tumors have not been consistently studied by morphology, immunohistochemistry, or molecular techniques. CASE PRESENTATION: We report three unusual cases of parotid gland poorly-differentiated sarcomatoid malignancy investigated by fine-needle aspiration and studied histologically, by immunohistochemistry and molecular investigations. Aspirates showed poorly specific polymorphous sarcomatoid malignancy in all cases. Histologically, all cases were polymorphous high-grade malignancies, and additionally, one case showed epithelial structures and was finally classified as salivary carcinosarcoma. Immunohistochemistry showed classical melanocytic markers negativity but positivity for PRAME, CD10, and WT1 in all three tumors and for CD56 in two tumors, which can potentially be supportive of melanocytic origin. Although not entirely specific, molecular characterization also suggested the melanocytic lineage of these tumors. CONCLUSION: Although rare, primary malignant melanoma of salivary gland was already described, but undifferentiated/dedifferentiated amelanotic forms are unknown in this localization up today. Further case reports of similar presentations are required to confirm the unequivocal primary origin of these obscure neoplasms in the parotid gland.

[A Case of Multidomain Integrated Treatment Strategy 
for Complex Primary Pulmonary Sarcomatoid Carcinoma].

Pulmonary sarcomatoid carcinoma (PSC) is a rare and highly malignant tumor, which includes the following five pathologic types: pleomorphic carcinoma, spindle cell carcinoma, giant cell carcinoma, carcinosarcoma and pulmonary blastoma. The onset of PSC is occult with non-specific clinical symptoms and signs. The clinical manifestations include irritating cough, bloody sputum, dyspnea, chest pain and so on, which are closely related to the growth and invasion site of the tumor. PSC tends to metastasize early, so most patients are already in local advanced stage or advanced stage with a median survival of 9 months at the time of hospital visit. A patient with primary PSC which led to 90% stenosis in central airway was treated by combined method of vascular and tracheoscopic intervention in our respiratory center. This treatment prolonged the patient's survival time and got a satisfactory effect at 19-month follow-up after surgery. Herein we report the case for clinical reference.
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Clinical and multiparametric MRI features for differentiating uterine carcinosarcoma from endometrioid adenocarcinoma.

INTRODUCTION: The purpose of our study was to differentiate uterine carcinosarcoma (UCS) from endometrioid adenocarcinoma (EAC) by the multiparametric magnetic resonance imaging (MRI) features. METHODS: We retrospectively evaluated clinical and MRI findings in 17 patients with UCS and 34 patients with EAC proven by histologically. The following clinical and pathological features were evaluated: post- or pre-menopausal, clinical presentation, invasion depth, FIGO stage, lymphaticmetastasis. The following MRI features were evaluated: tumor dimension, cystic degeneration or necrosis, hemorrhage, signal intensity (SI) on T2-weighted images (T2WI), relative SI of lesion to myometrium on T2WI, T1WI, DWI, ADCmax, ADCmin, ADCmean (RSI-T2, RSI-T1, RSI-DWI, RSI-ADCmax, RSI-ADCmin, RSI-ADCmean), ADCmax, ADCmin, ADCmean, the maximum, minimum and mean relative enhancement (RE) of lesion to myometrium on the arterial and venous phases (REAmax, REAmin, REAmean, REVmax, REVmin, REVmean). Receiver operating characteristic (ROC) analysis and the area under the curve (AUC) were used to evaluate prediction ability. RESULTS: The mean age of UCS was higher than EAC. UCS occurred more often in the postmenopausal patients. UCS and EAC did not significantly differ in depth of myometrial invasion, FIGO stage and lymphatic metastasis. The anterior-posterior and transverse dimensions were significantly larger in UCS than EAC. Cystic degeneration or necrosis and hemorrhage were more likely occurred in UCS. The SI of tumor on T2WI was more heterogeneous in UCS. The RSI-T2, ADCmax, ADCmean, RSI-ADCmax and RSI-ADCmean of UCS were significantly higher than EAC. The REAmax, REAmin, REAmean, REVmax, REVmin and REVmean of UCS were all higher than EAC. The AUCs were 0.72, 0.71, 0.86, 0.96, 0.89, 0.84, 0.73, 0.97, 0.88, 0.94, 0.91, 0.69 and 0.80 for the anterior-posterior dimension, transverse dimension, RSI-T2, ADCmax, ADCmean, RSI-ADCmax, RSI-ADCmean, REAmax, REAmin, REAmean, REVmax, REVmin and REVmean, respectively. The AUC was 0.997 of the combined of ADCmax, REAmax and REVmax. Our study showed that ADCmax threshold value of 789.05 (10-3mm2/s) can differentiate UCS from EAC with 100% sensitivity, 76.5% specificity, and 0.76 AUC, REAmax threshold value of 0.45 can differentiate UCS from EAC with 88.2% sensitivity, 100% specificity, and 0.88 AUC. CONCLUSION: Multiparametric MRI features may be utilized as a biomarker to distinguish UCS from EAC.

Spinal intramedullary uterine carcinosarcoma metastasis.

Intramedullary spinal cord metastases (ISCM) are a rare and challenging manifestation of metastatic cancer that have devastating impacts on the individual's neurological function, survival expectancy and overall quality of life. Given the rarity and poor prognosis, there is a lack of consensus in management. Uterine carcinosarcoma itself is a rare cancer, accounting for less than 3% of all uterine cancers. It carries a poor prognosis, with only one-third of patients surviving beyond 5 years. There are no previous reports of uterine carcinosarcoma metastases to the spinal cord. Here, we present the case of a woman in her late 70s with a uterine carcinosarcoma intramedullary metastasis that was refractory to radiotherapy treatment and responded favourably to surgical debulking.

Clinicopathological characteristics of odontogenic carcinosarcoma: A systematic review.

BACKGROUND: The aim of the present systematic review was to summarize evidence on odontogenic carcinosarcoma, analyzing clinical, epidemiological, imaging, histopathological, immunohistochemical, therapeutic, and prognostic features of this tumor. MATERIALS AND METHODS: This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Searches were performed in the Ovid MEDLINE (Wolters Kluwer), PubMed (National Library of Medicine), Web of Science (Thomson Reuters), Scopus (Elsevier), and LILACS (Latin American and Caribbean Center on Health Sciences Information) databases, without publication date or language restrictions. Case reports or case series of OCS reporting clinical, radiological, and histopathological data that confirmed the diagnosis were selected. The Joanna Briggs Institute-University of Adelaide tool was used for critical appraisal of the included articles. RESULTS: Odontogenic carcinosarcoma is a rare, aggressive tumor associated with high mortality; however, the metastasis rate is low. The tumor has a male predilection. The mean patient age is 40 years, but there is no predilection for age. The left posterior mandible is the most affected site, but no specific radiographic features have been reported. CONCLUSION: Given its rarity, dentists, oral-maxillofacial surgeons, and physicians need to be aware of odontogenic carcinosarcoma in order to increase the diagnostic potential, preventing delays in diagnosis and treatment and thus contributing to lower morbidity of the tumor.

Carcinosarcoma of the parotid gland: a case report and review of the literature.

BACKGROUND: Carcinosarcoma of the parotid gland is an extremely rare malignancy comprising of 0.04-0.16% of all salivary gland tumors. This is the first case of an adenoid cystic carcinoma with chondrosarcoma to the best of our knowledge. They consist of distinct carcinomatous and sarcomatous components and may arise de novo or from a preexisting pleomorphic adenoma. CASE PRESENTATION: Herein we present a case of an 80-year-old white female who presented with progressively increasing left facial swelling over 6 weeks. Magnetic Resonance Imagining revealed a mass (3.4 cm) in the parotid gland with a predominant cystic/necrotic component. The cytology was atypical (Milan3) and a total parotidectomy and selective lymph node dissection was done. The resection showed extensive necrosis with high grade sarcomatous (chondrosarcoma) areas. The epithelial component was adenoid cystic carcinoma with perineural invasion. The patient is currently undergoing radiotherapy of the tumor bed and skull base due to propensity of perineural invasion of the adenoid cystic component. The most common carcinomas in carcinosarcomas of salivary glands are adenocarcinoma and squamous cell carcinoma. CONCLUSION: Carcinosarcoma is a high-grade aggressive lesion with a poor prognosis and should be treated aggressively. More studies are needed to understand the origin of these tumors.

A rare case of thyroid carcinosarcoma arising from recurrent papillary thyroid cancer: Case report and review of the literature.

BACKGROUND: Thyroid carcinosarcoma represents a rare subtype of thyroid cancer, distinguished by its unique histopathology-simultaneous malignant epithelial and mesenchymal cells. The occurrence of thyroid carcinosarcoma arising from recurrent papillary thyroid cancer is exceptionally infrequent. METHODS: Study outlines a patient's thyroid carcinosarcoma journey, covering presentation, recurrence, diagnostics, surgeries, and follow-up. A PubMed search gathered data on pathological features and treatment approaches for thyroid carcinosarcoma. RESULTS: The patient initially diagnosed with papillary thyroid cancer underwent thyroidectomy, neck dissection, and radioactive iodine therapy. Recurrence revealed thyroid carcinosarcoma, featuring papillary carcinoma, squamous cell carcinoma, and spindle cell components. Total laryngectomy followed by adjuvant radiotherapy and chemotherapy. The patient was followed for 17 months with no evidence of disease. CONCLUSIONS: This extraordinary case exemplifies a rare instance of local relapse in form of thyroid carcinosarcoma following an initial diagnosis of papillary thyroid carcinoma. Surgical resection and chemoradiotherapy show promising outcomes in managing this challenging condition.

A phase 2 trial of zanidatamab in HER2-overexpressed advanced endometrial carcinoma and carcinosarcoma (ZW25-IST-2).

OBJECTIVE: HER2 overexpression is associated with decreased overall survival in metastatic endometrial cancer. Trastuzumab with chemotherapy has demonstrated efficacy for first-line management of advanced HER2+ endometrial carcinoma, but HER2-directed therapy in the recurrent setting is limited. Zanidatamab (ZW25), a humanized, bispecific antibody that simultaneously binds the 2 distinct HER2 epitopes bound by trastuzumab and pertuzumab, has demonstrated safety and activity in HER2+ tumors. Here, we report the results of a phase 2, open-label study evaluating the efficacy and safety of zanidatamab in patients with HER2+ metastatic endometrial carcinoma/carcinosarcoma who received prior treatment. METHODS: We enrolled 16 patients with HER2+ endometrial carcinoma/carcinosarcoma after progression on ≤2 lines of therapy on a single-arm phase 2 study of zanidatamab. The primary endpoint was overall response rate (ORR; complete or partial response) by Response Evaluation Criteria in Solid Tumors version 1.1. HER2 immunohistochemistry and fluorescence in situ hybridization (FISH) were performed on pretreatment samples. Intratumor HER2 genetic heterogeneity was assessed. RESULTS: This study did not meet its primary efficacy endpoint. Although a clinical benefit rate of 37.5% was observed by 24 weeks, only 1 patient achieved a partial response (ORR, 6.2%). Eight patients had HER2 intratumor heterogeneity or lacked HER2 amplification by FISH. Decreased HER2 expression on repeat pretreatment samples was observed in 3 (75%) of 4 patients evaluated. CONCLUSIONS: We observed a low response rate to zanidatamab in recurrent HER2+ endometrial carcinoma/carcinosarcoma, which may be driven by downregulation of HER2 expression. Repeat HER2 testing should be considered prior to second-line HER2-directed therapy. CLINICALTRIALS: govidentifier: NCT04513665.

Incidence and treatment outcomes of ovarian carcinosarcoma from the national cancer registry of Korea.

OBJECTIVE: To investigate the incidence and survival outcomes of ovarian carcinosarcoma in Korea between 1999 and 2018. METHODS: Patients diagnosed with ovarian carcinosarcoma between 1999 and 2018 were identified from the Korea Central Cancer Registry (KCCR) and their information was collected. Age-standardized incidence rates (ASRs), annual percent changes (APC), and relative survival rates of ovarian carcinosarcoma were calculated and compared to those of epithelial ovarian cancer. RESULTS: According to the KCCR, 458 cases of ovarian carcinosarcoma were detected, and accounted for 1.5% (458/30,679) of all epithelial ovarian cancers in Korea between 1999 and 2018. The ASR of ovarian carcinosarcoma between 1999 and 2018 was 0.064 per 100,000 women. The incidence rate of ovarian carcinosarcoma increased during the study period, with an ASR of 0.029 per 100,000 in 1999 and 0.073 per 100,000 in 2018. The APC of ovarian carcinosarcoma during 1999-2018 was 5.86 (p<0.001). The median overall survival (OS) of patients with ovarian carcinosarcoma was 39 months, and the 5-year OS rate was 42.5%. Among ovarian carcinosarcomas, patients with localized stages showed better clinical outcomes than those with regional or distant stages (5-year OS, 60.8%, 57.9%, and 32.8%, respectively; p<0.001). In addition, younger (<50 years) patients showed better OS than older (≥50 years) patients (5-year OS, 52.6% vs. 40.2%; p<0.001). CONCLUSION: Our nationwide registry-based study demonstrated that the incidence of ovarian carcinosarcoma increased from 1999 to 2018 in Korea. Patients with advanced-stage disease and older age (≥50 years) had poorer survival outcomes.