HER2 Status in Low-grade Serous Ovarian Tumors.

Using immunohistochemistry, we examined a large cohort of 135 ovarian tumors, made up of 96 low-grade serous carcinomas (LGSCs) and 39 serous borderline tumors (micropapillary variant, mSBT), with the aim of exploring their HER2 status (overexpression). We followed with comprehensive genomic analyses on this sample set from our previous study, which revealed HER2 mutation in 5% (4/75) of LGSC and 10% (3/29) of mSBT. No cases were evaluated as HER2-positive, but 6 LGSCs and 1 mSBT were scored as HER2 1+, and 2 LGSCs and 1 mSBT showed the so-called HER2 "ultra-low" phenotype. This could be of clinical value as a potential therapeutical target concerning emerging therapeutic treatments (antibody conjugates). However, the clinical significance of this expression still needs to be established.

Neuroendocrine Marker Expression in Primary Non-neuroendocrine Epithelial Tumors of the Ovary: A Study of 551 Cases.

Expression of neuroendocrine (NE) markers in primary ovarian non-NE epithelial tumors has rarely been evaluated. The aim of our study was to evaluate the expression of the most widely used NE markers in these neoplasms and to determine any prognostic significance of NE marker expression. The cohort consisted of 551 primary ovarian tumors, including serous borderline tumors, low-grade serous carcinomas, high-grade serous carcinomas (HGSC), clear cell carcinomas, endometroid carcinomas, mucinous borderline tumors, and mucinous carcinomas. Immunohistochemical analysis was performed using antibodies against INSM1, synaptophysin, chromogranin, and CD56 on tissue microarray. Positivity for INSM1, synaptophysin, chromogranin, and CD56 was most frequently observed in mucinous tumors (48.7%, 26.0%, 41.5%, and 100%, respectively). The positivity for these NE markers was mostly restricted to nonmucinous elements distributed throughout the tumor. The mucinous borderline tumor and mucinous carcinomas groups had similar proportions of positivity (mucinous borderline tumor: 53%, mucinous carcinomas: 39%). In the other tumor types, except for HGSC, there was only focal expression (5%-10%) or negativity for NE markers. HGSC showed high CD56 expression (in 26% of cases). Survival analysis was only performed for CD56 in HGSC as this was the only group with sufficient positive cases, and it showed no prognostic significance. Except for mucinous tumors, expression of NE markers in non-NE ovarian epithelial tumors is low. CD56 expression in HGSC occurs frequently but is without diagnostic or prognostic value.

New staging of endometrial carcinoma - FIGO 2023.

AIM: To review the changes in the new version of the FIGO 2023 staging system for endometrial cancer. METHODS AND RESULTS: The new FIGO 2023 endometrial cancer staging system provides key updates for the diagnosis and treatment of endometrial cancer. An important step in diagnosis is molecular classification, which allows more accurate risk stratification for recurrence and the identification of targeted therapies. The new staging system, based on the recommendations of the international societies ESGO, ESTRO and ESP, incorporates not only the description of the pathological and anatomical extent of the disease, but also the histopathological characteristics of the tumour, including the histological type and the presence of lymphovascular space invasion. In addition, the staging system uses molecular testing to classify endometrial cancers into four prognostic groups: POLEmut, MMRd, NSMP and p53abn. Each group has its own specific characteristics and prognosis. The most significant changes have occurred in stages I and II, in which the sub-staging better reflects the biological behaviour of the tumour. This update increases the accuracy of prognosis and improves individualized treatment options for patients with endometrial cancer. CONCLUSION: The updated FIGO staging of endometrial cancer for 2023 incorporates different histologic types, tumour features, and molecular classifications to better reflect the current improved understanding of the complex nature of several endometrial cancer types and their underlying bio logic behaviour. The aim of the new endometrial cancer staging system is to better define stages with similar prognosis, allowing for more precise indication of individualised adjuvant radiation or systemic treatment, including the use of immunotherapy.

Preoperative and postoperative staging in endometrial cancer - a prospective study.

OBJECTIVE: The aim of this study was to determine how often changes the stage of the tumour in definitive histology against preoperative clinical stage in patient cohort with diagnosed endometrial cancer. METHODS: We evaluated prospectively a cohort of 166 patients with endometrial cancer. They all underwent abdominal hysterectomy, bilateral salpingo-oophorectomy, sentinel lymph node biopsy. Patients with high-risk tumours also pelvic lymfadenectomy. We collected data of preoperative diagnostic biopsy and postoperative definitive histology. The data were statistically processed. RESULTS: Detection of sentinel lymph node was successful in 71.1%, bilateral successful detection was in 40.6%. Discrepancy of tumour grade between preoperative biopsy and definitive histology was generally 31.4%. Upgrading of the tumour was in 22 (14.4%) cases, downgrading in 26 (17%) cases. Upgrade from low-risk to high-risk group of tumours was noticed in eight cases. Histopathological tumour type changed in 6.6%, 4.6% moved to histopathologic high-risk group. The tumour stage changed in definite histology in 57.3%, in 19.2% of cases moved from stage low/intermediate-risk group to intermediate-high/high-risk disease group. CONCLUSION: Correct assessment of preoperative clinical stage and histological grade of endometrial cancer is burdened with a high inaccuracy rate. A lot of cases is up-staged after surgical staging and moved to intermediate-high/high-risk disease group. Results confirm the importance of oncogynaecologic centre II. evaluation of histopathology findings from diagnostic biopsies made in referring hospitals. Sentinel lymph node biopsy should be performed even in clinically low/intermediate-risk disease group.

Primary Mucinous Tumors of the Ovary: An Interobserver Reproducibility and Detailed Molecular Study Reveals Significant Overlap Between Diagnostic Categories.

Primary ovarian mucinous tumors represent a heterogeneous group of neoplasms, and their diagnosis may be challenging. We analyzed 124 primary ovarian mucinous tumors originally diagnosed as mucinous borderline tumors (MBTs) or mucinous carcinomas (MCs), with an emphasis on interobserver diagnostic agreement and the potential for diagnostic support by molecular profiling using a next-generation sequencing targeted panel of 727 DNA and 147 RNA genes. Fourteen experienced pathologists independently assigned a diagnosis from preset options, based on a review of a single digitized slide from each tumor. After excluding 1 outlier participant, there was a moderate agreement in diagnosing the 124 cases when divided into 3 categories (κ = 0.524, for mucinous cystadenoma vs MBT vs MC). A perfect agreement for the distinction between mucinous cystadenoma/MBT as a combined category and MC was found in only 36.3% of the cases. Differentiating between MBTs and MCs with expansile invasion was particularly problematic. After a reclassification of the tumors into near-consensus diagnostic categories on the basis of the initial participant results, a comparison of molecular findings between the MBT and MC groups did not show major and unequivocal differences between MBTs and MCs or between MCs with expansile vs infiltrative pattern of invasion. In contrast, HER2 overexpression or amplification was found only in 5.3% of MBTs and in 35.3% of all MCs and in 45% of MCs with expansile invasion. Overall, HER2 alterations, including mutations, were found in 42.2% of MCs. KRAS mutations were found in 65.5% and PIK3CA mutations in 6% of MCs. In summary, although the diagnostic criteria are well-described, diagnostic agreement among our large group of experienced gynecologic pathologists was only moderate. Diagnostic categories showed a molecular overlap. Nonetheless, molecular profiling may prove to be therapeutically beneficial in advanced-stage, recurrent, or metastatic MCs.

Twenty years of experience with less radical fertility-sparing surgery in early-stage cervical cancer: Pregnancy outcomes.

INTRODUCTION: The standard procedure in cervical cancer is radical hysterectomy and pelvic lymphadenectomy (PLND). Because of the increasing age of women bearing children, fertility has become a major challenge. We present pregnancy results after less radical fertility-sparing surgery in women with IA1, LVSI positive, IA2 and IB1 (<2 cm, infiltration less than half of the cervical stroma). MATERIALS AND METHOD: All women (n = 91) underwent laparoscopic sentinel lymph node mapping with frozen section followed by PLND and "selective parametrectomy" (removal of afferent lymphatic channels from the paracervix) if sentinel nodes (SLN) are negative. If lymph nodes were verified negative by definitive histopathology, patients were treated by simple trachelectomy (IB1) or large cone (IA1/IA2) biopsy 1 week after primary surgery. RESULTS: From 1999 to 2018, 91 women were enrolled in the study (median age 29.1 years, range 21-40). Fertility was spared in 76 (83.5%) women; 13 (17.1%) women did not plan future pregnancy and 63 (82.9%) had pregnancy desires. Fifty-four of 63 women conceived (pregnancy rate 85.7%) and 48 of 63 delivered 58 babies (delivery rate 76.2%). Thirty-nine women delivered in term (67.2%): 13 women between 32 and 36 + 6 weeks of pregnancy, 3 between 28 and 31 + 6 weeks and 3 between 24 and 27 + 6 weeks. Only one woman still plans pregnancy. One woman is currently pregnant. CONCLUSION: The goal of fertility-sparing surgery is to produce good oncological results and promising pregnancy outcomes. Pregnancy results after less radical fertility-sparing procedures show promise (pregnancy rate 82.9% and delivery rate 76.2%).

The efficacy of human papillomavirus vaccination in the prevention of recurrence of severe cervical lesions.

OBJECTIVE: A review of current knowledge on the efficacy of human papillomavirus (HPV) vaccination in preventing recurrent severe cervical lesions after excisional surgical treatment. METHODS AND RESULTS: HPV infection is necessary for the development of most cervical precancerous lesions and cervical cancers. Currently, three prophylactic vaccines against HPV infection are available on the market: bivalent Cervarix, quadrivalent Gardasil (formerly Silgard) and nonavalent Gardasil9. All three prophylactic vaccines show high effect in preventing the development of precancerous lesions. The highest efficacy is achieved in the HPV naive population. The surgical excision of severe cervical precancers is the standard approach. However, guidelines regarding HPV vaccination at the time of conisation are not clearly determined. Women diagnosed with severe cervical lesions have mostly not been vaccinated against HPV so far. Therefore, it is beneficial to understand the importance and efficacy of HPV vaccination at the time of conisation in preventing recurrent precancerous lesions. The exact value of HPV vaccination in the context of surgical excision of precancerous lesions remains unclear, but vaccination is definitely valuable in reducing the risk of recurrence. Vaccination timing seems to be more favorable before surgery. However, the ideal timing of vaccination is not established. Some of these questions are likely to be answered by the results of ongoing randomized controlled trials. CONCLUSION: Adjuvant HPV vaccination in the setting of surgical treatment for cervical precancerous lesion is significantly associated with a reduced risk of recurrence. HPV vaccination should be strongly considered as adjuvant therapy, especially in young patients undergoing conisation for a severe cervical lesion.

Epidemiology and significance of surgical margins in the management of HPV-associated vulvar precancers (H-SIL) - analysis of own data.

OBJECTIVE: Epidemiology and evaluation of the importance of surgical margins in the treatment of vulvar H-SIL - analysis of own data. MATERIAL AND METHODS: The prospective study included women dia-gnosed with HPV-associated vulvar epithelial neoplasia from 10/2016 to 1/2022. A total of 65 women were included. After surgical treatment, the women were distributed to groups according to surgical margins and were followed-up at regular intervals. RESULTS: Seventeen women (26%) dia-gnosed with HPV-associated vulvar intraepithelial neoplasia were under 49 years, whereas 48 women (74%) were older than 49 years. Recurrence rates of HPV-associated precancers were 12.3%, 1.5% and 3.1% in excisions with positive margins up to 1mm peripheral margins and 1-3mm peripheral margins, respectively. The risk of recurrence when the lesion reaches the margin is statistically significant, compared to a healthy margin of 1-3mm. CONCLUSION: Keeping the minimal healthy margin (1-3mm) seems to be an acceptable risk of recurrence of HPV-associated vulvar intraepithelial neoplasia with positive cosmetic effect and minimal risk of disturbing the psychosexual functions of women. Long-term regular follow-up is necessary.

Twenty years of experience with less radical fertility-sparing surgery in early-stage cervical cancer: Oncological outcomes.

INTRODUCTION: The standard procedure in cervical cancer is radical hysterectomy (RH) and pelvic lymphadenectomy (PLND). Because of the increasing age of women at childbirth, fertility becomes a major challenge. We present 20 years of experience with two-step less radical fertility-sparing surgery in women with IA1, LVSI positive, IA2 and IB1 (<2 cm, infiltration less than half of stromal invasions. MATERIALS AND METHOD: Preoperative workout consisted of histopathological diagnosis and magnetic resonance imaging along with ultrasonographic volumetry. We then performed laparoscopic sentinel lymph node mapping (SLNM) with frozen section (FS) followed by PLND and "selective parametrectomy" (removal of afferent lymphatic channels from the paracervix) in case of a negative result. If verified by definitive histopathology, patients were treated by simple trachelectomy (IB1) or large cone (IA1/IA2) biopsy 1 week after primary surgery. RESULTS: From 1999 to 2018, 91 women were enrolled in the study (median age 29.1 years, range 21-40). Of these 91 women, 51 (56.0%) were nulliparous. The detection rate of SLNs was 100% per patient and the specific side detection rate 96.7%. Positive lymph nodes were diagnosed in nine cases (9.8%). These women then underwent RH. Fertility was spared in 80 women but 4 recurred locally (5.0%). The mortality rate was 0.0%. The median follow-up was 149 months. CONCLUSION: Less radical fertility-sparing surgery with SLNM is safe in cervical cancers <2 cm at the largest diameter and infiltrating less than half of the cervical stroma. The recurrence rate is acceptable with no mortality. Morbidity with this procedure is low. Extended and accurate follow-up is necessary and human papillomavirus - high risk (HPV-HR tests seem to be useful in such follow-up assessment.

Lymph node metastasis of parotid gland high-grade adenoid-cystic carcinoma.

Adenoid cystic carcinoma (ACC) is one of the most common salivary gland malignancies. In rare cases, ACC undergoes high-grade transformation, which is associated with poor prognosis, in contrast to relatively long survival in the conventional ACC. Conventional ACC is characterized by typical histopathology showing glandular arrangement with sharply demarcated lumina, the tumor cells have sparse cytoplasm and angulated hyperchromatic nuclei. ACCs undergoing high-grade transformation lack these morphological features. In this paper we present a case of 46 years old female patient presenting with locally advanced tumor of the parotid gland and neck lymphadenopathy, coming for surgery. A suspect lymph node was sent to freeze section histology. Large non-cohesive cells with vesicular nuclei and prominent nucleoli along with well persevered lymph node architecture were seen in the frozen slide. This finding lead to suspicion of a lymphoma, the surgery finished in the extent of superficial parotidectomy and selective neck dissection of regions II-IV. Subsequent histopathological examination of formalin-fixed lymph node proofed epithelial nature of the atypical cells by p63 positivity. In the parotid gland resection specimen, an ACC with high-grade component was indentified. The high-grade ACC shared cell morphology with the lymph node metastasis. 17 from 20 lymph neck nodes contained metastases of high-grade ACC. Interestingly, there was strong CD117 expression in the high-grade ACC, whereas the conventional part was fully negative. To the best of our knowledge, the high-grade ACC of the parotid gland was reported only in 10 cases in the medical literature.

Tailoring neoadjuvant chemotherapy for a pregnant patient diagnosed with IB2 squamous cervical carcinoma.

The incidence of cancer during pregnancy is steadily rising because of the postponement of plans for childbearing. One of the most common cancers diagnosed during pregnancy is cervical cancer. Diagnosis of most cases usually occurs in the early stages, but there are still cases of tumors staged IB2 and higher. In these cases, the treatment strategy entails administration of neoadjuvant chemotherapy. However, a universally recognized standardized regimen for neoadjuvant chemotherapy treatment of cervical cancer during pregnancy has yet to be established. The chemotherapy agents used during treatment are known for their fetal adverse effects. The aim of the therapy is to attain full-term pregnancy while minimizing fetal toxicity and decreasing tumor size. In this case report, we present a first-time sequential chemotherapy administration to minimize the cumulative toxicity of individual regimens and demonstrate the benefits for the patient and fetus.

The role of stathmin expression in the differential diagnosis, prognosis, and potential treatment of ovarian sex cord-stromal tumors.

BACKGROUND: Stathmin, a cytosolic microtubule-destabilizing phosphoprotein involved in the regulation of mitosis, is widely expressed in various malignancies and acts as an adverse prognostic factor. Our research analyzed its immunohistochemical expression on a large cohort of ovarian sex cord-stromal tumors, evaluating its potential utility in differential diagnosis, prognosis, and therapeutic application. METHODS: We examined 390 cases of ovarian sex cord-stromal tumors including 281 adult granulosa cell tumors (AGCT), 5 juvenile granulosa cell tumors (JGCT), 33 Sertoli-Leydig cell tumors (SLCT), 50 fibromas/thecomas (F/T), 11 Leydig cell tumors/steroid cell tumors (LCT/SterCT), 5 sex-cord stromal tumors NOS (SCST-NOS), 3 Sertoli cell tumors (SCT), and 2 sclerosing stromal tumors (ScST). Immunohistochemical analysis was performed using TMAs. RESULTS: Strong expression (> 50%) was observed in all cases of AGCT, JGCT, SLCT, SCST-NOS, SCT and 1 ScST. The other case of ScST exhibited mild expression (5-10%). The negative cases included exclusively F/T and LCT/SterCT, with F/T showing 24% of negative cases and LCT/SterCT comprising 64% of negative cases. CONCLUSION: The results of our study indicate that stathmin is neither a prognostic marker nor suitable for the differential diagnosis of challenging cases of ovarian sex cord-stromal tumors. However, its predictive value may be theoretically significant, as a decrease in stathmin expression potentialy influences response to chemotherapy treatment.

An extensive immunohistochemical analysis of 290 ovarian adult granulosa cell tumors with 29 markers.

The current knowledge about the immunohistochemical features of adult granulosa cell tumor (AGCT) is mostly limited to the "traditional" immunohistochemical markers of sex cord differentiation, such as inhibin, calretinin, FOXL2, SF1, and CD99. Knowledge about the immunohistochemical markers possibly used for predictive purpose is limited. In our study, we focused on the immunohistochemical examination of 290 cases of AGCT classified based on strict diagnostic criteria, including molecular testing. The antibodies used included 12 of the "diagnostic" antibodies already examined in previous studies, 10 antibodies whose expression has not yet been examined in AGCT, and 7 antibodies with possible predictive significance, including the expression of HER2, PD-L1, CTLA4, and 4 mismatch repair (MMR) proteins. The results of our study showed expression of FOXL2, SF1, CD99, inhibin A, calretinin, ER, PR, AR, CKAE1/3, and CAIX in 98%, 100%, 90%, 78%, 45%, 41%, 94%, 82%, 26%, and 9% of AGCT, respectively. GATA3, SATB2, napsin A, MUC4, TTF1, and CD44 were all negative. PTEN showed a loss of expression in 71% of cases and DPC4 in 4% of cases. The aberrant staining pattern (overexpression) of p53 was found in 1% (3/268) of cases, 2 primary tumors, and 1 recurrent case. Concerning the predictive markers, the results of our study showed that AGCT is microsatellite stable, do not express PD-L1, and are HER2 negative. The CTLA4 expression was found in almost 70% of AGCT tumor cells.

DICER1 Variants in Pediatric and Young Adult Thyroid Nodules.

Background: Recent studies have suggested that pathogenic variants of the DICER1 gene could be a driver of alterations in some pediatric thyroid nodules, but data are still limited. The aim of this study was to detect variants in the DICER1 gene in a large cohort of pediatric thyroid nodules and then correlate them with clinicopathological data, with a focus on the disease prognosis in patients with thyroid carcinoma. Methods: This retrospective cohort study consisted of 350 pediatric and young adult patients (aged 2-21 years) with thyroid nodules, from whom 275 fresh-frozen thyroid nodule samples and 92 fine-needle aspiration biopsy (FNAB) samples were collected. After an analysis of variants in major genetic alterations of thyroid tumors, variants in the DICER1 gene were identified using next-generation sequencing and multiplex ligation-dependent probe amplification methods. Peripheral blood was analyzed from patients with DICER1-positive tumors. The results of genetic analysis were then correlated with clinicopathological data. Results: Variants in the DICER1 gene were detected in a total of 24/350 (6.9%; 95%CI [4.4;10.0]) pediatric and young adult patients, respectively, in 10/119 (8.4%; [4.1;14.9]) patients with benign fresh-frozen tissue, in 8/141 (5.7%; [1.9;9.5]) with papillary thyroid carcinoma (PTC) and in 6/86 (7.0%; [4.1;14.6]) patients with FNAB. No other gene alteration was found in DICER1-positive samples. Germline DICER1 variants were identified in 11/24 (45.8%; [25.6;67.2]) patients. Two somatic (biallelic) variants in the DICER1 gene were found in 9/24 (37.5%; [18.8;59.4]) thyroid nodules. Somatic deletions of at least 3 Mbp long were revealed in 2/24 (8.3%; [1.0;27.0]) cases. DICER1-positive PTCs were significantly associated with the follicular subtype of PTC (p = 0.001), encapsulation (p = 0.006) and were larger in size (p = 0.035), but with no extrathyroidal extension (p = 0.039), and less frequent lymph node metastases (p = 0.003) compared with DICER1-negative PTCs. Patients with DICER1-positive PTC had an excellent response to treatment in 75% of cases. Conclusions: Variants of the DICER1 gene are frequently found in the thyroid nodules of pediatric and young adult patients. In our patients, DICER1-positive PTCs showed low invasiveness. Our findings support considering more conservative management for DICER1-positive low-risk PTCs.

Somatic Genomic and Transcriptomic Characterization of Primary Ovarian Serous Borderline Tumors and Low-Grade Serous Carcinomas.

Low-grade serous carcinoma (LGSC) may develop from serous borderline tumor (SBT) tissue, where the micropapillary type (mSBT) presents the highest risk for progression. The sensitivity of LGSC to standard chemotherapy is limited, so alternative therapeutic approaches, including targeted treatment, are needed. However, knowledge about the molecular landscape of LGSC and mSBT is limited. A sample set of 137 pathologically well-defined cases (LGSC, 97; mSBT, 40) was analyzed using capture DNA next-generation sequencing (727 genes) and RNA next-generation sequencing (147 genes) to show the landscape of somatic mutations, gene fusions, expression pattern, and prognostic and predictive relevance. Class 4/5 mutations in the main driver genes (KRAS, BRAF, NRAS, ERBB2, USP9X) were detected in 48% (14/29) of mSBT cases and 63% (47/75) of LGSC cases. The USP9X mutation was detected in only 17% of LGSC cases. RNA next-generation sequencing revealed gene fusions in 6 of 64 LGSC cases (9%) and 2 of 33 mSBT cases (9%), and a heterogeneous expression profile across LGSC and mSBT. No molecular characteristics were associated with greater survival. The somatic genomic and transcriptomic profiles of 35 mSBT and 85 LGSC cases are compared for the first time. Candidate oncogenic gene fusions involving BRAF, FGFR2, or NF1 as a fusion partner were identified. Molecular testing of LGSC may be used in clinical practice to reveal therapeutically significant targets.

Chemotherapy drives tertiary lymphoid structures that correlate with ICI-responsive TCF1+CD8+ T cells in metastatic ovarian cancer.

PURPOSE: Patients with high-grade serous ovarian carcinoma (HGSOC) are virtually insensitive to immune checkpoint inhibitors (ICIs) employed as standalone therapeutics, at least in part reflecting microenvironmental immunosuppression. Thus, conventional chemotherapeutics and targeted anticancer agents that not only mediate cytotoxic effects but also promote the recruitment of immune effector cells to the HGSOC microenvironment stand out as promising combinatorial partners for ICIs in this oncological indication. EXPERIMENTAL DESIGN: We harnessed a variety of transcriptomic, spatial and functional assays to characterize the differential impact of neo-adjuvant paclitaxel-carboplatin on the immunological configuration of paired primary and metastatic HGSOC biopsies as compared to NACT-naïve HGSOC samples from 5 independent patient cohorts. RESULTS: We found neo-adjuvant chemotherapy (NACT)-driven endoplasmic reticulum stress and calreticulin exposure in metastatic HGSOC lesions culminates with the establishment of a dense immune infiltrate including follicular T cells (TFH cells), a prerequisite for mature tertiary lymphoid structure (TLS) formation. In this context, TLS maturation was associated with an increased intratumoral density of ICI-sensitive TCF1+PD-1+ CD8+ T cells over their ICI-insensitive TIM-3+PD-1+ counterparts. Consistent with this notion, chemotherapy coupled with a PD-1-targeting ICI provided a significant survival benefit over either therapeutic approach in syngeneic models of HGSOC bearing high (but not low) tumor mutational burden. CONCLUSION: Altogether, our findings suggest that NACT promotes TLS formation and maturation in HGSOC lesions, de facto preserving an intratumoral ICI-sensitive T-cell phenotype. These observations emphasize the role of rational design, especially relative to the administration schedule, for clinical trials testing chemotherapy plus ICIs in patients with HGSOC.

Tertiary lymphoid structures and B cells determine clinically relevant T cell phenotypes in ovarian cancer.

Intratumoral tertiary lymphoid structures (TLSs) have been associated with improved outcome in various cohorts of patients with cancer, reflecting their contribution to the development of tumor-targeting immunity. Here, we demonstrate that high-grade serous ovarian carcinoma (HGSOC) contains distinct immune aggregates with varying degrees of organization and maturation. Specifically, mature TLSs (mTLS) as forming only in 16% of HGSOCs with relatively elevated tumor mutational burden (TMB) are associated with an increased intratumoral density of CD8+ effector T (TEFF) cells and TIM3+PD1+, hence poorly immune checkpoint inhibitor (ICI)-sensitive, CD8+ T cells. Conversely, CD8+ T cells from immunologically hot tumors like non-small cell lung carcinoma (NSCLC) are enriched in ICI-responsive TCF1+ PD1+ T cells. Spatial B-cell profiling identifies patterns of in situ maturation and differentiation associated with mTLSs. Moreover, B-cell depletion promotes signs of a dysfunctional CD8+ T cell compartment among tumor-infiltrating lymphocytes from freshly isolated HGSOC and NSCLC biopsies. Taken together, our data demonstrate that - at odds with NSCLC - HGSOC is associated with a low density of follicular helper T cells and thus develops a limited number of mTLS that might be insufficient to preserve a ICI-sensitive TCF1+PD1+ CD8+ T cell phenotype. These findings point to key quantitative and qualitative differences between mTLSs in ICI-responsive vs ICI-irresponsive neoplasms that may guide the development of alternative immunotherapies for patients with HGSOC.

HER2 status as a potential predictive biomarker for ovarian clear cell carcinoma.

Ovarian clear cell carcinoma (OCCC) is a subtype of ovarian carcinoma characterized by unique biological features and highly malignant characteristics including low chemosensitivity. Therefore, new therapeutic targets are needed. These could include the downstream pathways of receptor tyrosine kinases, especially the human epidermal growth factor receptor 2 (HER2). Our main objective was to characterize the HER2 status using immunohistochemistry (IHC) and FISH on 118 OCCCs, also considering the novel paradigm of HER2-zero and HER2-low status. Other aims included determination of the association between HER2 status and survival, HER2 gene DNA and RNA NGS analysis, HER2 gene expression analysis, and correlation between IHC and gene expression in HER2-zero and HER2-low cases. Cases with HER2 overexpression/amplification accounted for 5.1% (6/118), with additional 3% harbouring HER2 gene mutation. The remaining 112 (94.9%) cases were HER2-negative. Of these, 75% were classified as HER2-zero and 25% as HER2-low. This percentage of HER2 aberrations is significant concerning their possible therapeutic influence. Cases from the HER2-zero group showed significantly better survival. Although this relationship lost statistical significance in multivariate analysis, the results have potential therapeutic significance. HER2 gene expression analysis showed a significant correlation with HER2 IHC status in the entire cohort (HER2-positive vs. HER2-negative), while in the cohort of only HER2-negative cases, the results did not reach statistical significance, suggesting that gene expression analysis would not be suitable to confirm the subdivision into HER2-low and HER2-zero. Our results also emphasize the need for standardized HER2 testing in OCCC to determine the best predictor of clinical response.

A comprehensive immunohistochemical analysis of 26 markers in 250 cases of serous ovarian tumors.

BACKGROUND: We examined a large cohort of serous tubo-ovarian tumors with 26 immunohistochemical markers, with the aim to assess their value for differential diagnosis and prognosis. METHODS: Immunohistochemical analyses with 26 immunomarkers were performed on 250 primary tubo-ovarian tumors including 114 high grade serous carcinomas (HGSC), 97 low grade serous carcinomas (LGSC), and 39 serous borderline tumors (micropapillary variant, mSBT). The associations of overall positivity with clinicopathological characteristics were evaluated using the chi-squared test or Fisher's Exact test. RESULTS: We found significantly different expression of p53, p16, ER, PR, PTEN, PAX2, Mammaglobin, RB1, Cyclin E1, stathmin, LMP2, L1CAM, CD44, and Ki67 in HGSCs compared to LGSCs. No significant differences were found between LGSC and mSBT. None of the other included markers (PAX8, ARID1A, HNF1B, Napsin A, CDX2, SATB2, MUC4, BRG1, AMACR, TTF1, BCOR, NTRK) showed any differences between the investigated serous tumors. Regarding the prognosis, only PR and stathmin showed a statistically significant prognostic meaning in LGSCs, with better overall survival (OS) and recurrence-free survival (RFS) in cases positive for PR, and worse outcome (RFS) for stathmin. None of the study markers showed prognostic significance in HGSCs. CONCLUSION: We provided an extensive immunohistochemical analysis of serous ovarian/tubo-ovarian tumors. Although we found some differences in the expression of some markers in HGSCs compared to LGSCs, only p53, p16, and Ki67 seem to be useful in real diagnostic practice. We also suggested the best discriminative cut-off for Ki67 (10% of positive tumor cells) for distinguishing HGSC from LGSC. We found prognostic significance of PR and stathmin in LGSCs. Moreover, the high expression of stathmin could also be of predictive value in ovarian carcinomas as target-specific anti-stathmin effectors are potential therapeutic targets.

Immunohistochemical expression of PRAME in 485 cases of epithelial tubo-ovarian tumors.

Preferentially expressed antigen of melanoma (PRAME) is a cancer/testis antigen selectively expressed in somatic tissues and various solid malignant tumors and is associated with poor prognostic outcome. Our research aimed to comprehensively compare its expression in a large cohort of tubo-ovarian epithelial tumors and examine its correlation with our clinico-pathologic data, as well as to assess its potential use in diagnostics and therapy.We examined 485 cases of epithelial tubo-ovarian tumors including 107 clear cell carcinomas (CCC), 52 endometroid carcinomas (EC), 103 high grade serous carcinomas (HGSC), 119 low grade serous carcinomas (LGSC)/micropapillary variant of serous borderline tumors (mSBT), and 104 cases of mucinous carcinomas (MC)/mucinous borderline tumors (MBT). The immunohistochemical analysis was performed using TMAs.The highest levels of expression were seen in EC (60%), HGSC (62%), and CCC (56%), while expression in LGSC/mSBT (4%) and MC/MBT (2%) was rare. The clinico-pathologic correlations and survival analysis showed no prognostic significance.The results of our study showed that PRAME is neither prognostic nor a suitable ancillary marker in the differential diagnosis of tubo-ovarian epithelial tumors. Nevertheless, knowledge about the PRAME expression may be important concerning its potential predictive significance, because targeting PRAME as a potential therapeutic option is currently under investigation.