•Primary peritoneal clear cell carcinoma can arise from endometriotic implants within the abdomen and pelvis.•Immunohistochemistry can be used to confirm primary disease site. Endometriotic origin can be inferred based on clinical history and intraoperative findings suggestive of endometriosis.•While no standardized treatment exists, consideration should be given to cytoreductive surgery with adjuvant chemotherapy. Adjuvant radiation can also be considered for local control.

Endometriosis is a medical condition affecting at least up to 10% of women of reproductive age. This condition occurs when ectopic endometrial glands and stroma implant outside the uterus and there are several theories regarding the underlying origins of the disease. Endometriosis is one of the major causes of severe dysmenorrhoea, chronic pelvic pain and infertility. While endometriosis is generally a non-malignant condition, it rarely may transform into an invasive cancer, and increase the risk for epithelial ovarian cancer, notably endometrioid or clear cell ovarian cancer. Despite the increased risk, the mechanisms behind the development of endometriosis-associated ovarian cancer (EAOC) are not yet well understood. Recent investigations have delved into the intricate interplay between endometriosis and EAOC, exploring pathways involving oxidative stress, inflammation, hyperestrogenism, and the discovery of genetic mutations within endometriotic lesions that hint at a transition towards invasive carcinoma. Efforts have been made to identify intermediary lesions between endometriosis and EAOC, which may enable earlier detection of endometriosis at risk of malignant transformation or even prevention of the transformation altogether. However, given the rarity of this malignancy, there is still the risk of late or missed diagnosis, with the risk of inappropriate management being offered to the patient, and the higher risk of poor prognosis and increased morbidity and mortality. This scoping review aims to summarize existing data on EAOC, with a focus on endometrioid and clear cell histologic subtypes. It also provides insights into its identification, prognosis, and delineating management strategies, seeking to provide a holistic understanding of the complexities surrounding EAOC, facilitating further research and the development of more effective prevention and treatment approaches.

BACKGROUND: Ovarian clear cell carcinoma (OCCC) shares treatment strategies with epithelial ovarian cancer (EOC). Due to OCCC\'s rarity, there\'s a lack of prospective studies on its surgery, resulting in heterogeneous and limited existing data. This study aims to clarify the prognostic significance of lymphadenectomy in OCCC patients.
METHODS: We systematically searched Web of Science, Scopus, PubMed, and Google Scholar until July 2023 for studies investigating lymphadenectomy\'s effects on OCCC patients. We calculated pooled hazard ratios (HR) with 95% confidence intervals (CI). This study is registered in PROSPERO (CRD42021270460).
RESULTS: Among 444 screened articles, seven studies (2883 women) met inclusion criteria. Our analysis revealed that lymphadenectomy significantly improved disease-specific survival (DSS) (HR = 0.76, 95%CI = 0.60-0.95, P = 0.02) and disease-free survival (DFS) (HR = 0.58, 95%CI = 0.34-0.99, P = 0.05). However, it did not significantly affect overall survival (OS) (HR = 0.80, 95%CI = 0.60-1.06, P = 0.12) or progression-free survival (PFS) (HR = 0.95, 95%CI = 0.64-1.42, P = 0.79). Notably, some earlier studies reported no survival benefit, warranting cautious interpretation.
CONCLUSIONS: Lymphadenectomy does not significantly enhance OS and PFS for OCCC but does improve DFS and DSS. Tailoring treatment to individual patient profiles is imperative for optimal outcomes. Precise preoperative or intraoperative lymph node metastasis detection is essential for identifying candidates benefiting from lymphadenectomy. Collaborative international efforts and an OCCC database are pivotal for refining future treatment strategies.

Pembrolizumab, a PD-1 ICI is approved for the adjuvant treatment of postnephrectomy patients with clear cell RCC in some countries worldwide. However, recent negative data from randomized clinical trials (RCT) with another ICIs makes the benefit of this treatment uncertain. A systematic review and study-level meta-analysis was performed to evaluate the benefit of disease-free survival (DFS) with adjuvant ICI treatment for patients with localized and/or metastatic resected RCC. Using the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement, a systematic search was performed in PUBMED/MEDLINE, Scopus and EMBASE up to September 15, 2022. The statistical analysis was performed by ProMeta 3 software in intention-to-treat (ITT) population and in predetermined subgroups. Four RCT totalizing 3407 patients were included in this analysis. Systemic immunotherapy was pembrolizumab, atezolizumab, nivolumab, and ipilimumab plus nivolumab in 496, 390, 404, and 405 patients, respectively. In the ITT population there was a nonstatistically significant DFS benefit with adjuvant ICI (HR: 0.85, 95% CI: 0.69-1.04). Regarding the subgroups, there was a DFS benefit for PD-L1 positive (HR: 0.72; 95% CI: 0.55-0.94), intermediate-high risk patients (HR: 0.77; 95% CI: 0.63-0.94), and patients with sarcomatoid component (HR: 0.66; 95% CI: 0.43-0.99). This meta-analysis did not demonstrate a statistically significant DFS benefit in overall population, however considering the heterogeneity between the RCTs the use of adjuvant ICI should be individualized.

BACKGROUND: Sclerosing odontogenic carcinoma is an exceedingly rare gnathic malignancy first described by Koutlas et al. in 2008, and was only recently designated as a distinct pathologic entity by World Health Organization in the 2017 Classification of Head and Neck Tumors. To date, fewer than fifteen cases of this neoplasm have been reported in the English language literature. This tumor is characterized by thin cords, strands, and small nests of epithelium in a densely sclerotic stroma. In some tumor foci, the density of the stroma may be sufficient to compress the epithelial component beyond detection in the absence of immunohistochemistry, thus rendering this entity a particularly challenging diagnosis in small sample sizes.
METHODS: A 55-year-old male presented with an asymptomatic lesion of posterior left maxilla. Cone beam computed tomography (CBCT) demonstrated a large, well-defined bony lesion with scalloped border, spanning from canine to first molar. External root resorption of the adjacent teeth was also noted. Microscopic examination of the biopsy specimen revealed an odontogenic tumor with features consistent with sclerosing odontogenic carcinoma. Immunohistochemical staining was performed to confirm the diagnosis.
RESULTS: The tumor was positive for CK5/6, CK19, E-cadherin, p63 and negative for CK20 and CK7.
CONCLUSIONS: Sclerosing odontogenic carcinoma is a rare, low-grade malignancy of odontogenic origin, which represents a diagnosis of exclusion in many cases. An immunohistochemical profile demonstrating positivity for markers including CK5/6, CK19, p63, and E-cadherin, in addition to a set of pertinent negative findings, can aid in the diagnosis of this tumor. This entity appears to lack metastatic potential despite its locally destructive behavior and a common histologic finding of perineural invasion.

Ovarian teratoid carcinosarcoma involves an epithelial tumor of the Müllerian duct and an immature neuroepithelium, which is a characteristic of immature teratomas. Here, we describe the case of a 60-year-old woman who underwent surgery for a stage IC3 ovarian malignancy. The tumor showed a variety of histological features, including clear cell carcinoma, immature teratoma, and rhabdomyosarcoma, and a PIK3CA mutation was detected at the same locus in each. Two months after surgery and before the start of chemotherapy, multiple bone and liver metastases were found. Four courses of combination therapy with vincristine, actinomycin D and cyclophosphamide, the standard chemotherapy regimen for pediatric rhabdomyosarcoma, were administered, and a complete response was achieved. After a 2-month rest period, the patient developed recurrent peritoneal dissemination and underwent 6 courses of paclitaxel, carboplatin, and bevacizumab chemotherapy, resulting in a partial response. This is the eighth reported case of ovarian teratoid carcinosarcoma. This tumor has a very aggressive course, but initially responds to chemotherapy. However, survival over 5 years has not been reported, and elucidation of the pathogenesis and development of new treatment methods are needed.
UNASSIGNED: The online version contains supplementary material available at 10.1007/s13691-022-00571-w.

Herlyn-Werner-Wunderlich syndrome (HWWS) is a rare congenital urogenital anomaly characterized by uterine didelphys, unilateral blind hemivagina, and ipsilateral renal agenesis. We present a very rare case of HWWS-associated cervical cancer in which the presence of a genital anomaly was not noticed until the patient experienced postmenopausal vaginal bleeding. A 74-year-old nulliparous Japanese woman presented with vaginal bleeding. Pre-treatment workup revealed uterine didelphys, obstructed hemivagina/hemicervix, renal agenesis, and cancer development from the remnant-obstructed hemivagina/hemicervix. The patient was diagnosed with HWWS and HWWS-associated vaginal or cervical cancer, treated with radical surgery, and a diagnosis of clear cell carcinoma (CCC) of the uterine cervix was histopathologically confirmed. A literature review revealed an increased incidence of CCC in women with HWWS.

UNASSIGNED: Clear cell carcinoma of abdominal wall is a very rare and aggressive disease. It is mostly related to malignant transformation of abdominal wall endometriosis. This paper provides a new case report and a literature review of primitive abdominal wall clear cell carcinoma.
UNASSIGNED: A 45-year-old woman with a history of a two previous caesarian section presented to the outpatient department with a tumor mass evolving since 10 years in the lower right quadrant of her abdomen. Imaging studies revealed a voluminous subcutaneous mass developing at the expense of the anterior abdominal wall. Surgical resection of the mass was performed. Histopathological examination along with immunohistochemical analysis were consistent with clear cell carcinoma. Biopsies of the endometrium and ovaries were performed and were negative for malignancy. The patient underwent therefore a hysterectomy with bilateral salpingo-oophorectomy which did not reveal any disease. The diagnosis of primitive clear cell carcinoma of the abdominal wall was then confirmed.
UNASSIGNED: Primitive clear cell carcinoma of the abdominal wall is an extremely rare form of cancer with usually poor prognosis. Clinicians must be aware of the possibility of malignancy of any swelling mass occurring near or within a caesarean section scar.
UNASSIGNED: Reporting more such cases is still needed to further progress in the understanding of this malignancy in addition to the development of treatment strategies.

UNASSIGNED: Clear cell carcinoma arising from the malignant transformation of endometriosis is a rare but aggressive cancer often diagnosed in perimenopausal women. Malignant transformation constitutes a rare complication of endometriosis, with only a few cases reported in the medical literature. Clear cell carcinoma and endometrioid carcinoma are the two most common histological subtypes associated with malignant endometriosis.
UNASSIGNED: A 61-year-old Afro-Trinidadian woman underwent a total abdominal hysterectomy and bilateral salpingo-oophorectomy for a degenerated uterine leiomyoma. Histopathology demonstrated an isolated finding of clear cell carcinoma occurring within an endometriotic cyst on the uterine serosa. Subsequent surgical staging demonstrated early-stage disease associated with a high-risk histological subtype and the patient was referred for adjuvant chemoradiotherapy.
UNASSIGNED: This case highlights the clinical manifestations and treatment modalities employed for an early-stage high-risk subtype of endometriosis-associated cancer. In light of the few publications on this clinical entity, we hope to raise awareness of this unique complication of endometriosis and contribute evidence to the development of standardized treatment protocols.

Endometriosis-associated ovarian cancer represents the most common form of malignancy associated with this benign disease. It has a better prognosis than most types of ovarian cancer, with endometrioid adenocarcinoma and clear cell carcinoma as the main histological types. Clinical presentation is usually nonspecific and tumor biomarkers can be misleading, since they can also be elevated in the presence of benign ovarian endometriosis. We report a case of a 52-year-old woman with known ovarian and deep pelvic endometriosis, who developed ovarian clear cell carcinoma within a large endometrioma. The imaging findings highlight the key role of magnetic resonance imaging in detecting suspicious features such as loss of the \"T2 shading\" sign, loss of high T1 signal of an endometrioma, or the presence of mural nodules. Early detection of these malignancies is fundamental for adequate surgical treatment and overall outcome.