KSHV/HHV8-negative primary effusion lymphoma
Effusion-based lymphoma, KSHV/HHV8-negative (also termed Type II PEL) has been described by some researchers. These cases closely resemble KSHV/HHV8-positive (also termed Type I PEL) but have yet to be defined by the World Health Organization (2017). Compared to Type I PEL, Type II PEL occurs more often in older individuals, is less often associated with EBV, and more often afflicts individuals who lack evidence of being immunocompromised. That is, the majority of HHV-8-negative EBL cases do not evidence a potentially PEL causative agent, such as HIV, EBV, HCV, or iatrogenic immunodeficiency, except for old age and, in 20% to 40% of cases, the presence of hepatitis C virus infection. Type II PEL also tends to involve malignant plasmablasts, anaplastic cells, and/or Reed-Sternberg-like cells that have somewhat different expression patters of protein markers (e.g. the malignant cells in Type II PEL frequently express CD20 but often do not express CD30) and gene abnormalities (e.g. the malignant cells in Type II PEL more commonly evidence rearrangements in their Myc, BCL2, and BCL6 genes) than the malignant cells in Type I PEL. The response to treatment and prognosis of Type II PEL is poor but may be somewhat better than the treatment-responsiveness and prognosis of Type I PEL.
Pathology
Characteristic feature is the identification of intimately related syncytiotrophoblasts and cytotrophoblasts without formation of definite placental type villi. Since choriocarcinomas include syncytiotrophoblasts (beta-HCG producing cells), they cause elevated blood levels of beta-human chorionic gonadotropin. Syncytiotrophoblasts are large multi-nucleated cells with eosinophilic cytoplasm. They often surround the cytotrophoblasts, reminiscent of their normal anatomical relationship in chorionic villi. Cytotrophoblasts are polyhedral, mononuclear cells with hyperchromatic nuclei and a clear or pale cytoplasm. Extensive hemorrhage is a common finding. Treatment
Since gestational choriocarcinoma (which arises from a hydatidiform mole) contains paternal DNA (and thus paternal antigens), it is exquisitely sensitive to chemotherapy. The cure rates, even for metastatic gestational choriocarcinoma, more than 90% when using chemotherapy for invasive mole and choriocarcinoma.As of 2019, treatment with either single-agent methotrexate or actinomycin-D is recommended for low-risk disease, while intense combination regimens including EMACO (etoposide, methotrexate, actinomycin D, cyclophosphamide and vincristine (Oncovin) are recommended for intermediate or high-risk disease.Hysterectomy (surgical removal of the uterus) can also be offered to patients >40 years of age or those for whom sterilisation is not an obstacle. It may be required for those with severe infection and uncontrolled bleeding. Choriocarcinoma arising in the testicle is rare, malignant and highly resistant to chemotherapy. The same is true of choriocarcinoma arising in the ovary. Testicular choriocarcinoma has the worst prognosis of all germ-cell cancers. References
External links

00976 at CHORUS