POLE exonuclease domain mutations in endometrial carcinoma: a case report

Endometrial carcinoma (EC) harboring POLE exonuclease domain mutations occurs in 5-15% of ECs and frequently affects young women with low body mass index (BMI). It presents at early stage as high grade endometrioid histotype with intense tumor infiltrating lymphocytes and has good clinical outcomes and favorable prognosis. In this article we report the case of a 32-year-old woman with endometriod EC (EEC) exhibiting a "ultramutated" molecular profile and an excellent prognosis despite tumor size and grading. Herein, to highlight the importance of defining POLE status in ECs for both clinical and therapeutic implications for patients.

Placental site trophoblastic tumor (PSTT): a case report and review of the literature

Placental site trophoblastic tumor (PSTT), also known as atypical choriocarcinoma, syncytioma, chorioepitheliosis or trophoblastic pseudotumor, is a rare gestational trophoblastic disease (0.25-5% of all trophoblastic tumors) and it is composed by neoplastic proliferation of intermediate trophoblasts at placental implantation site. It consists of aggregates or sheets of large, polyhedral to round, predominantly mononucleated cells with a characteristic vascular and myometrial invasion. Main differential diagnoses are gestational choriocarcinoma (GC) and epitelioid trophoblastic tumor (ETT). We present a case of PSTT in a 25-year-old woman. Neoplastic cells showed moderate/high nuclear pleomorphism, abundant amphophilic, eosinophilic and clear cytoplasm, numerous mitotic figures (10 mitoses/10 HPF), and myometrial invasion. Other features are necrosis, vascular invasion with replacement of myometrial vessels by tumor cells and hemorrhage. The patient showed typical low serum β-hCG levels and high serum humane placental lactogen (hPL) levels.

BRCA gene amplification in primary peritoneal high-grade serous carcinoma patient with intrinsic resistance to platinum treatment: a case report

Platinum-based chemotherapy is the standard chemotherapy for high grade serous ovarian cancer and primary peritoneal high-grade serous carcinoma. PARP inhibitors have changed the paradigm of the treatment in platinum-sensitive ovarian cancers and primary peritoneal high-grade serous carcinoma with BRCA1/2 mutation or homologous recombination deficiency (HRD). Platinum-resistant ovarian and primary peritoneal high-grade serous carcinoma have a lower chance to treat and have worse outcomes. We described a case of patient with a platinum resistant primary peritoneal high-grade serous carcinoma with a rare somatic BRCA2 amplification. There are no guidelines for the treatment of ovarian cancer or primary peritoneal high-grade serous carcinoma with BRCA2 amplification. BRCA2 amplification could result in extreme homologous recombination repair (HRR) pathway efficiency and in less platinum sensitivity, which could be a molecular signature for platinum resistance. Free platinum chemotherapy regimens could be more effective in cases with BRCA2 amplification. Further studies are necessary to establish better approaches and strategies for oncological management and treatment in BRCA2 amplification high grade ovarian cancer and primary peritoneal high-grade serous carcinoma.

NTRK gene fusions in solid tumors: agnostic relevance, prevalence and diagnostic strategies

A number of innovative drugs, developed for precision medicine, have shown impressive activity in neoplastic patients with rare molecular targets, independently from the site and type of tumor. This gave rise to the concept of agnostic treatments in oncology. The detection of such rare targets is a prerequisite for these treatments and is nowadays one of the main challenges in diagnostic molecular pathology. Various algorithms, new diagnostic strategies and pathological workflows have been suggested to help pathologists in the detection of these rare molecular alterations. An emblematic example of biological targets for agnostic treatments is represented by genetic rearrangements affecting members of the Neurotrophic Tyrosine Receptor Kinase (NTRK) gene family. These gene rearrangements have an unusual dual mode of distribution: the first, at high frequency in some very rare neoplasms, and the second with extremely lower frequencies in more common tumors. Even in the context of an agnostic approach, knowledge of site, histotype and prevalence of the tumors carrying these genetic lesions may be helpful to guide the pathologist in the daily effort in search of these molecular alterations. This review examines the prevalence of NTRK gene fusions in different forms of solid tumors, based on the largest studies to date, reports a comprehensive diagnostic algorithm and an innovative pathological workflow for rapid screening.