Comprehensive immunohistochemical analysis based on the origin of leiomyosarcoma

Diagnostic criteria, biological behavior, and treatment approaches of leiomyosarcomas (LMS) may differ according to the origin of the tumor. This is important in terms of patient's management, especially in tumors located in the peritoneum and retroperitoneal sites. In our study, we aimed to demonstrate the immunophenotypic characteristics of uterine and extra-uterine LMS using a large antibody panel, and to determine whether they potentially play a role in the differences among these tumor groups. Between 2006 and 2018, 29 uterine and 42 extra-uterine primary LMS were included in this study. Using tissue samples taken from the areas that best represented the tumor, an immunohistochemical study was performed on the blocks prepared by tissue micro-array method with estrogen and progesterone receptor (PR), WT-1, SMA, desmin, caldesmon, calponin, p16, p53, MDM2, CDK4, bcl-2, cyclin D1, fascin, EMMPRIN, FOXM1, c-erb-B2, c-Myc, PAX8, and CD117. Staining results of uterine and extra-uterine LMS were evaluated with these 20 antibodies. In uterine LMS compared with extra-uterine LMS, estrogen receptor (48% vs. 12%), PR (62% vs. 21%), desmin (79% vs. 50%), and EMMPRIN (69% vs. 45%) staining rate was detected higher. In extra-uterine LMS, caldesmon (88% vs. 69%), c-Myc (33% vs. 10%), and cyclin D1 (52% vs. 28%) were stained higher than uterine LMS (p < 0.05). No significant staining difference was detected with other antibodies. We concluded that estrogen receptor, PR, desmin, EMMPRIN, caldesmon, c-Myc, and cyclin D1 antibodies may help to determine primary origin of the tumor in LMS cases.

Malignant Perivascular Epithelioid Cell Tumor (PEComa) of the Uterus as Part of the Hereditary Cancer Syndrome: A Case Diagnosed with Multiple Malignancies

A perivascular epithelioid cell tumor (PEComa) is an uncommon mesenchymal tumor composed of perivascular epithelioid cells. These tumor cells show variable immunoreactivity for both melanocytic and myogenic markers. Occurrence of PEComa has been reported at various anatomical sites, including the gynecological tract, uterus being the most common. Although most patients have sporadic PEComas, a subset may be associated with the inactivation of TSC1 or TSC2 genes and the occurrence of TFE3 gene fusions. However, a relationship between PEComas and other tumors is rare. We report a 41-year-old female patient with malignant PEComa who was admitted to the hospital with a complaint of vaginal bleeding. Because she had previously been diagnosed with colorectal and breast carcinomas at an early age, we performed a comprehensive genetic analysis to identify molecular alterations present in her background that unveiled multiple malignancy predispositions. Next-generation sequencing (NGS) analysis revealed two heterozygous germline pathogenic variants in the ATM and TP53 genes and a heterozygous variant of unknown significance (VUS) in the BRCA2 gene. The patient was diagnosed with the Li-Fraumeni Syndrome owing to the medical and family history and also the presentation of a pathogenic mutation of the TP53 gene. There are very few case reports in the literature describing PEComa in the Li-Fraumeni syndrome, and this is the first report of a uterine PEComa in a patient with Li-Fraumeni syndrome.

Uterine Leiomyoma with Massive Lymphoid Infiltrate in a Patient with History of Assisted In-Vitro Fertilization

Uterine leiomyomas are the most common benign tumors of the gynecological tract. Massive lymphocytic infiltration has been reported rarely in uterine leiomyomas and it has been described as a pathogenetic correlation with gonadotropin-releasing hormone agonists. Uterine leiomyomas with massive lymphoid infiltration have to be differentiated from non-Hodgkin lymphomas. We report a case of a woman without a history of gonadotropin-releasing hormone agonist treatment, who presented with a uterine leiomyoma that increased in size after the procedure of assisted in-vitro fertilization, and associated with massive nodular lymphoid infiltrate simulating, morphologically, a non-Hodgkin lymphoma. Uterine leiomyoma with massive lymphocytic infiltration is a very rare entity, probably of reactive significance, which has to be differentiated from diseases that need a systemic therapeutic approach.