The emerging and challenging role of PD-L1 in patients with gynecological cancers: An updating review with clinico-pathological considerations.

Over recent years, there has been significant progress in the development of immunotherapeutic molecules designed to block the PD-1/PD-L1 axis. These molecules have demonstrated their ability to enhance the immune response by prompting T cells to identify and suppress neoplastic cells. PD-L1 is a type 1 transmembrane protein ligand expressed on T lymphocytes, B lymphocytes, and antigen-presenting cells and is considered a key inhibitory checkpoint involved in cancer immune regulation. PD-L1 immunohistochemical expression in gynecological malignancies is extremely variable based on tumor stage and molecular subtypes. As a result, a class of monoclonal antibodies targeting the PD-1 receptor and PD-L1, known as immune checkpoint inhibitors, has found successful application in clinical settings. In clinical practice, the standard method for identifying suitable candidates for immune checkpoint inhibitor therapy involves immunohistochemical assessment of PD-L1 expression in neoplastic tissues. The most commonly used PD-L1 assays in clinical trials are SP142, 28-8, 22C3, and SP263, each of which has been rigorously validated on specific platforms. Gynecologic cancers encompass a wide spectrum of malignancies originating from the ovaries, uterus, cervix, and vulva. These neoplasms have shown variable response to immunotherapy which appears to be influenced by genetic and protein expression profiles, including factors such as mismatch repair status, tumor mutational burden, and checkpoint ligand expression. In the present paper, an extensive review of PD-L1 expression in various gynecologic cancer types is discussed, providing a guide for their pathological assessment and reporting.

Atypical glandular cells and predictive features of malignancy in Pap smears: A retrospective monocentric study.

OBJECTIVE: The introduction of cytological screening with the Papanicolau smear significantly reduced cervical cancer mortality. However, Pap smear examination can be challenging, being based on the observer ability to decode different cytological and architectural features. This study aims to evaluate the malignancy rate of AGC (atypical glandular cells) category, investigating the relationships between cytological and histological diagnosis. METHODS: Eighty-nine patients, diagnosed as AGC at cytological evaluation and followed up with biopsy or surgical procedure at Policlinico Gemelli Hospital, Rome, Italy, were included in the study. The cytopathological architectural (feathering, rosette formation, overlapping, loss of polarity, papillary formation, three-dimensional formation) and nuclear (N/C ratio, nuclear enlargement and hyperchromasia, mitoses, nuclei irregularity, evident nucleoli) features of AGC were evaluated. Statistical analyses were performed to assess cyto-histological correlation and determine the relevance of architectural and nuclear features in the diagnosis of malignancy. RESULTS: Of the 89 AGC patients, 48 cases (53.93%) were diagnosed as AGC-NOS and 41 (46.07%) were diagnosed as AGC-FN, according to the Bethesda classification system. The follow-up biopsies or surgical resections revealed malignancy in 46 patients (51.69%). The rates of malignancy for AGC-NOS and AGC-FN were 35.41% and 70.73% respectively. Furthermore, analysing cytopathological features, we found that both architectural and nuclear criteria were statistically significant (p < 0.05). Only overlapping, nuclear irregularity and increased N/C ratio were not found to be statistically significant for detecting malignancy. CONCLUSIONS: Cytological diagnosis of glandular lesions remains a valid tool, when appropriate clinical correlation and expert evaluation are available.

Mismatch Repair Deficiency as a Predictive and Prognostic Biomarker in Endometrial Cancer: A Review on Immunohistochemistry Staining Patterns and Clinical Implications.

Among the four endometrial cancer (EC) TCGA molecular groups, the MSI/hypermutated group represents an important percentage of tumors (30%), including different histotypes, and generally confers an intermediate prognosis for affected women, also providing new immunotherapeutic strategies. Immunohistochemistry for MMR proteins (MLH1, MSH2, MSH6 and PMS2) has become the optimal diagnostic MSI surrogate worldwide. This review aims to provide state-of-the-art knowledge on MMR deficiency/MSI in EC and to clarify the pathological assessment, interpretation pitfalls and reporting of MMR status.

Endometrioid type adenocarcinoma in situ as a potential precursor lesion for extremely rare invasive endometrioid type adenocarcinoma of the cervix.

HPV-independent in situ adenocarcinomas have been only recently added to the WHO 2020 classification. To date, little information has been published about HPVindependent precursor lesions. In particular, regardiong the extremely rare cervical endometrioid type adenocarcinoma thought to arise in the setting of cervical endometriosis, a premalignant lesion is still not well defined. In this short communication we describe a possible precursor to invasive cervical endometrioid type adenocarcinoma in a 39-yr-old patient, with a previous history of breast cancer.

Morphological and immunohistochemical evaluation in distinguishing post-radiotherapy serous-like endometrial change (PoRSEC) and serous endometrial intraepithelial carcinoma (SEIC).

Uteri from women undergoing chemoradiotherapy (CRT) may show reactive atypia which may mimic serous endometrial intraepithelial carcinoma (SEIC). We aimed to assess the prevalence and morphological/immunohistochemical features of post-radiotherapy serous-like endometrial changes (PoRSEC) in women undergone CRT for locally advanced cervical cancer, with a focus on the differential diagnosis with SEIC. Consecutive patients with locally advanced cervical cancer undergone CRT between 2011 and 2018 were reviewed. Endometrial histological specimens were assessed for the presence of PoRSEC. Twenty-two cases of SEIC were included for comparison. Immunohistochemistry for p53, p16, and Ki67 was performed. Out of 244 reviewed patients, 36 (14.7%) showed PoRSEC. The degree of nuclear atypia was similar between PoRSECs and SEIC. However, a papillary architecture with areas of confluent papillae was only observed in SEIC. SEIC cases showed a high mitotic activity as opposed to PoRSEC cases. The expression of p53 was aberrant in all SEICs but in none of the PoRSECs; however, 13/36 PoRSECs showed p53 positivity in most tumor cells, potentially mimicking a mutation pattern. A block-type p16 expression was observed in all SEICs and in 16/36 PoRSECs. Mean Ki67 expression was 26.9% in SEIC (range 5-70%) and 8.16% in PoRSEC (range 5-35%). While SEIC showed sharp morphological and immunohistochemical demarcation, PoRSEC were more heterogenous and merged imperceptibly with normal endometrium. In conclusion, PoRSEC may mimic SEIC both morphologically and immunohistochemically. However, a papillary architecture with cytological demarcation is typically observed in SEIC but not in PoRSEC.