[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [General pathology](https://durgical.com/en/general-pathology/) › [Female genital tract](https://durgical.com/en/general-pathology/areas/female-genital/) › High-grade endometrial cancers: serous, clear cell, carcinosarcoma # High-grade endometrial cancers: serous, clear cell, carcinosarcoma - Lesion Three aggressive endometrial cancers of older women: they come from p53 damage rather than estrogen and spread to the abdomen early. Updated Nov 12, 2026 ## Key points - Serous: papillae and slit-like glandular spaces, marked nuclear atypia, many mitoses, psammoma bodies; p53 aberrant (strong diffuse or completely absent). - Serous endometrial intraepithelial carcinoma can already spread beyond the uterus. - Clear cell: clear or hobnail cells in papillary, tubulocystic or solid patterns; high grade by definition. - Carcinosarcoma: malignant glands plus malignant stroma, sometimes with heterologous elements (rhabdomyoblasts, cartilage); monoclonal; TP53 often mutated; prior pelvic radiation is a risk factor. - All three are staged surgically and treated aggressively; prognosis is worse than endometrioid carcinoma stage for stage. ## What it is Serous carcinoma, clear cell carcinoma and carcinosarcoma are high-grade endometrial cancers of older women that do not follow the estrogen pathway. Serous carcinoma arises from serous intraepithelial carcinoma on an atrophic endometrium or polyp, carries TP53 mutation in nearly all cases, and can seed the peritoneum while still tiny in the uterus. Carcinosarcoma contains both malignant epithelium and malignant mesenchyme but is a single clone, essentially a carcinoma that has partly turned into sarcoma, and has a poor outlook. ## Structure - Serous: complex papillae with tufts, cells with large pleomorphic nuclei, frequent abnormal mitoses; usually ER-low; a subset has HER2 amplification. - Clear cell: cells with glycogen-rich clear cytoplasm and hobnail nuclei bulging into lumens; Napsin A positive. - Carcinosarcoma: a bulky, fleshy, necrotic and haemorrhagic polypoid mass that may protrude through the cervical os; a high-grade carcinoma intimately mixed with a high-grade sarcoma. ## Step by step - In an atrophic endometrium, a cell acquires a TP53 mutation. - Genomic instability and copy-number changes follow rapidly. - The surface lesion (serous intraepithelial carcinoma) sheds cells through the tubes onto the peritoneum. - Invasive carcinoma develops; in carcinosarcoma part of the carcinoma undergoes epithelial-mesenchymal transition and becomes sarcoma. ## Markers - p53 aberrant - p16 strong - WT1 usually negative (helps separate from ovarian serous carcinoma) - Napsin A (clear cell) - HER2 (subset of serous) ## Clinical notes - Postmenopausal bleeding in an older woman, sometimes with ascites or an abdominal mass from early spread. - Surgery includes omentectomy and peritoneal sampling because spread may be microscopic. - Although uncommon, these tumours cause a disproportionate share of endometrial cancer deaths. ## Memory aid Serous is small and seeds early; the carcinosarcoma is a carcinoma wearing a sarcoma costume. ## Test yourself Think of the answer, then tap the question to see it. ## Which gene is mutated in nearly all serous endometrial carcinomas? TP53. ## Why can a tiny serous endometrial carcinoma have a high stage? Even serous intraepithelial carcinoma can shed cells to the peritoneum, so spread beyond the uterus is common when the uterine tumour is minimal. ## Is carcinosarcoma a collision of two tumours? No; it is monoclonal, a carcinoma in which part of the clone has become sarcomatous, and it behaves like a high-grade carcinoma. [Add to my cards (3)](https://durgical.app/estudiar/?add=/en/general-pathology/high-grade-endometrial-cancers-serous-clear-cell-carcinosarcoma/) [More Pathology questions →](https://durgical.com/en/practice/?f=pathology) ## Elsewhere in DurgiPedia - [Oncogenes and tumour suppressor genes](https://durgical.com/en/biochemistry/topics/oncogenes-and-tumour-suppressor-genes/) ## Connections ## Related 8 - [Endometrial carcinoma: types and molecular groups](https://durgical.com/en/general-pathology/endometrial-carcinoma-types-and-molecular-groups/) - [Endometrioid endometrial carcinoma](https://durgical.com/en/general-pathology/endometrioid-endometrial-carcinoma/) - [High-grade serous carcinoma](https://durgical.com/en/general-pathology/high-grade-serous-carcinoma/) - [Endometrial stromal tumours](https://durgical.com/en/general-pathology/endometrial-stromal-tumours/) - [Tumour suppressor genes: RB, TP53, APC, BRCA and the two-hit hypothesis](https://durgical.com/en/general-pathology/tumour-suppressor-genes-rb-tp53-apc-brca-and-the-two-hit-hypothesis/) - [Pathways of spread and the usual metastatic sites](https://durgical.com/en/general-pathology/pathways-of-spread-and-the-usual-metastatic-sites/) - [Differentiation and anaplasia: how a tumour cell looks under the microscope](https://durgical.com/en/general-pathology/differentiation-and-anaplasia-how-a-tumour-cell-looks-under-the-microscope/) - [Radiation and cancer: ultraviolet and ionizing](https://durgical.com/en/general-pathology/radiation-and-cancer-ultraviolet-and-ionizing/) ## Related conditions 2 - [Endometrial cancer](https://durgical.com/en/conditions/endometrial-cancer/) - [Soft tissue sarcomas (liposarcoma, leiomyosarcoma, rhabdomyosarcoma)](https://durgical.com/en/conditions/soft-tissue-sarcomas/) [← All of general pathology](https://durgical.com/en/general-pathology/) Educational content on the mechanisms of disease; not a diagnostic or treatment guide and no substitute for a health professional's advice. No doses are given. Sources: [Endometrial Cancer Treatment (PDQ®)–Health Professional Version](https://www.cancer.gov/types/uterine/hp/endometrial-treatment-pdq) (National Cancer Institute, 2026); [Uterine Sarcoma Treatment (PDQ®)–Health Professional Version](https://www.cancer.gov/types/uterine/hp/uterine-sarcoma-treatment-pdq) (National Cancer Institute, 2026). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/general-pathology/high-grade-endometrial-cancers-serous-clear-cell-carcinosarcoma/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/general-pathology/high-grade-endometrial-cancers-serous-clear-cell-carcinosarcoma/