BRCA1/2 alterations and reversion mutations in the area of PARP inhibitors in high grade ovarian cancer: state of the art and forthcoming challenges.

BRCA1/2 genes are part of homologous recombination (HR) DNA repair pathways in charge of error-free double-strand break (DSB) repair. Loss-of-function mutations of BRCA1/2 genes have been associated for a long time with breast and ovarian cancer hereditary syndrome. Recently, polyadenosine diphosphate-ribose polymerase inhibitors (PARPi) have revolutionized the therapeutic landscape of BRCA1/2-mutated tumors, especially of BRCA1/2 high-grade serous ovarian cancer (HGSC), taking advantage of HR deficiency through the synthetic lethality concept. However, PARPi efficiency differs among patients, and most of them will develop resistance, particularly in the relapse setting. In the current proposal, we aim to review primary and secondary resistance to PARPi in HGSC owing to BRCA1/2 alterations. Of note, as several mechanisms of primary or secondary resistance to PARPi have been described, BRCA1/2 reversion mutations that restore HR pathways are by far the most reported. First, the type and location of the BRCA1/2 primary mutation have been associated with PARPi and platinum-salt sensitivity and impact the probability of the occurrence and the type of secondary reversion mutation. Furthermore, the presence of multiple reversion mutations and the variation of allelic frequency under treatment underline the role of intratumor heterogeneity (ITH) in treatment resistance. Of note, circulating tumor DNA might help us to detect and characterize reversion mutations and ITH to finally refine the treatment strategy. Importantly, forthcoming therapeutic strategies, including combination with antiangiogenics or with targeted therapies, may help us delay and overcome PARPi resistance secondary to BRCA1/2 reversion mutations. Also, progression despite PARPi therapy does not preclude PARPi rechallenge in selected patients.

Uterine smooth muscle tumors: a multicenter, retrospective, comparative study of clinical and ultrasound features.

OBJECTIVE: To evaluate a wide range of clinical and ultrasound characteristics of different uterine smooth muscle tumors to identify features capable of discriminating between these types. METHODS: This was a retrospective, multicenter study that included 285 patients diagnosed with uterine smooth muscle tumors (50 leiomyosarcomas, 35 smooth muscle tumors of uncertain malignant potential, and 200 leiomyomas). The patients were divided into three groups based on the histological type of their tumors, and the groups were compared according to the variables collected. RESULTS: Leiomyosarcomas were more common in older and post-menopausal women. Compared with leiomyomas, smooth muscle tumors of uncertain malignant potential and leiomyosarcomas had similar ultrasound features such as absence of normal myometrium, multilocular appearance, hyper-echogenicity in case of uniform echogenicity, absence of posterior shadows, echogenic areas, and hyperechoic rim. Leiomyosarcomas were larger, had more cystic areas, and were associated with a higher prevalence of pelvic free fluid. Smooth muscle tumors of uncertain malignant potential were characterized by a higher frequency of International Federation of Gynecology and Obstetrics (FIGO) type 6-7, the absence of internal shadows, and, in the case of cystic area, the presence of a regular internal wall. Tumor outline varied among the three histological types. A color score of 1 was typical of leiomyoma, a color score 2 was mainly observed in leiomyomas and smooth muscle tumors of uncertain malignant potential, a color score 3 did not differ among the tumors, while a color of score 4 was related to leiomyosarcomas. When combining color scores 3 and 4, leiomyosarcomas and smooth muscle tumors of uncertain malignant potential showed a high percentage of both circumferential and intra-lesional vascularization. A cooked appearance was not statistically different among the tumors. CONCLUSIONS: Based on our findings, specific ultrasonographic features as well as age and menopausal status are associated with different uterine smooth muscle tumor types. Integration of these data can help the pre-operative assessment of these lesions for proper management.

Management of metastatic endometrial cancer: physicians' choices beyond the first line after approval of checkpoint inhibitors.

Introduction: Endometrial cancer (EC) represents 3.4% of all newly diagnosed cancer cases and is responsible for 2.1% of all cancer-related deaths. Approximately 10%-15% of women with EC are diagnosed with advanced-stage disease, resulting in a reported 5-year survival rate of only 17% for those with distant metastases. A better understanding of its molecular features has ushered in a new era of immunotherapy for the treatment of EC, allowing for alternative therapeutic approaches, even in cases of advanced disease. Methods: We administered a multi-choice online survey for Multicenter Italian Trials in Ovarian cancer and gynecologic malignancies (MITO) members. The questionnaire was available for 2 months, starting in October 2022. Our objective was to evaluate the current attitude of incorporating molecular characterization of EC into routine clinical practice, appraise the implementation of newly available therapies, and compare the outcomes with the previous survey conducted in April-May 2021 to ascertain the actual changes that have transpired during this recent time period. Results: The availability of molecular classification in Italian centers has changed in 1 year. Seventy-five percent of centers performed the molecular classification compared with 55.6% of the previous survey. Although this percentage has increased, only 18% performed all the tests. Significant changes have occurred in the administration of new treatments in EC patients in MITO centers. In 2022, 82.1% of the centers administrated dostarlimab in recurrent or advanced MMR-deficient (dMMR) EC experiencing disease progression after platinum-based chemotherapy regimens, compared to only 24.4% in 2021. In 2022, 85.7% of the centers already administrated the pembrolizumab plus lenvatinib combination as a second-line therapy for MMR-proficient (pMMR) patients with advanced or recurrent EC who had progressed from first-line platinum-based therapy. Conclusion: Both the therapeutic and diagnostic scenarios have changed over the last couple of years in MITO centers, with an increased prescription of immune checkpoint inhibitors and use of the molecular classification.

Retrospective Analysis of the Correlation of MSI-h/dMMR Status and Response to Therapy for Endometrial Cancer: RAME Study, a Multicenter Experience.

BACKGROUND: There is poor evidence regarding sensitivity to chemotherapy in endometrial cancer (EC) based on microsatellite instability (MSI)/mismatch repair (MMR) status. METHODOLOGY: The RAME study is a retrospective analysis aiming to assess response to chemotherapy in MSI-high (h)/deficient (d) MMR and MSI-low (l)/proficient (p) MMR EC patients. Primary endpoints were recurrence-free survival (RFS) for patients with localized disease and progression-free survival (PFS) and overall survival (OS) in patients with advanced/recurrent disease. RESULTS: A total of 312 patients treated between 2010 and 2022 in four high-volume Multicenter Italian Trial in Ovarian cancer and gynecological malignancies (MITO) centers were selected. In total, 239 patients had endometrioid EC (76.6%), 151 had FIGO stage I at diagnosis (48.9%) and 71 were MSI-h/dMMR (22.8%). Median age was 65 (range 31-91) years. Among patients with localized disease, median RFS was 100.0 months (95% CI 59.4-140.7) for MSI-l/pMMR and 120.9 months (60.0-181.8) for MSI-h/dMMR (p = 0.39). Seventy-seven patients received first-line chemotherapy for advanced/recurrent disease. Patients with MSI-h/dMMR ECs had a significantly worse OS (p = 0.039). In patients receiving platinum-based chemotherapy, no statistically significant differences in PFS (p = 0.21) or OS (p = 0.057) were detected, although PFS and OS were numerically longer in the MSI-l/pMMR population. CONCLUSIONS: Patients with metastatic MSI-h/dMMR EC receiving first-line chemotherapy had a significantly worse OS.

Doxorubicin combined with Trabectedin in systemic first-line M+/recurrent leiomyosarcoma patients.

PURPOSE OF REVIEW: Currently, the only systemic therapy approved for advanced leiomyosarcoma is Doxorubicin-based monotherapy. Despite disappointing progression-free survival (PFS) and overall survival (OS), no combination therapy has formally ever proven to be more effective. In this clinical setting, selecting the most efficient therapy is key, as most patients become quickly symptomatic with poor performance status.This review aims to describe the current emerging role of Doxorubicin and Trabectedin in first-line setting, compared with doxorubicin alone the current standard of treatment. RECENT FINDINGS: Previous randomized trials focusing on combination therapies (Doxorubicin + ifosfamide, doxorubicin + evofosfamide, doxorubicin + Olaratumab, or Gemcitabine + Docetaxel) never reported positive results on the primary endpoint (OS or PFS). For the first time, the randomized phase III LMS-04 demonstrated that Doxorubicin and Trabectedin have a better PFS and disease control rate (DCR) compared with Doxorubicin, with higher but still manageable toxicities. SUMMARY: In the first-line setting, the results of this trial were pivotal for numerous reasons; Doxorubicin-Trabectedin is the first combination that has been proven to be more effective in terms of PFS, ORR and trend of OS compared with doxorubicin alone; moreover, it is clear that trials regarding soft tissue sarcoma should strive to be histology-driven.

Effect of bevacizumab in advanced low grade serous ovarian cancer: Data from the MITO 22 trial.

OBJECTIVE: The aim of the present analysis was to explore the efficacy of Bevacizumab (Bev) on survival outcome in advanced low grade serous ovarian cancer (LGSOC) both in first line and in recurrent setting. METHODS: In retrospective observational multicenter study, we described the outcome of LGSOC patients enrolled in the MITO 22 study and treated with chemotherapy (CT) with or without Bev. Patients receiving Bev in first-line or in recurrence were considered and compared with patients receiving CT alone (stage III and IV in first line; platinum based-CT in second line). Descriptive and survival analyses were performed for each group. RESULTS: Out of 128 patients included in MITO 22, 46 LGSOC patients receiving Bev in first line setting or at the time of first recurrence were identified. In first line, 30 patients received Bev + CT and 65 CT alone and the median PFS were 47.86 months (95% CI: 31.48 - NR) and 22.63 months (95% CI 15-39.24) (p-value 0.0392), respectively. In the recurrent setting, 16 patients who received Bev + CT were compared to 33 women treated with platinum-based CT alone. Median PFS were 37.1 months (95% CI: 13.42-40.56) and 11.22 months (95% CI: 8.26-15.63) (p-value 0.013), respectively. CONCLUSIONS: Our study suggests that Bev might be effective in LGSOC both at diagnosis and at the time of relapse. These data warrants further studies.

Ki67 as a Predictor of Response to PARP Inhibitors in Platinum Sensitive BRCA Wild Type Ovarian Cancer: The MITO 37 Retrospective Study.

BACKGROUND: There is compelling need for novel biomarkers to predict response to PARP inhibitors (PARPi) in BRCA wild-type (WT) ovarian cancer (OC). METHODS: MITO 37 is a multicenter retrospective study aiming at correlating Ki67 expression at diagnosis with a clinical outcome following platinum treatment and PARPi maintenance. Clinical data were collected from high grade serous or endometroid BRCAWT OC treated with niraparib or rucaparib maintenance between 2010-2021 in 15 centers. Ki67 expression was assessed locally by certified pathologists on formalin-fixed paraffin embedded (FFPE) tissues. Median Ki67 was used as a cut-off. RESULTS: A total of 136 patients were eligible and included in the analysis. Median Ki67 was 45.7% (range 1.0-99.9). The best response to platinum according to median Ki67 was 26.5% vs. 39.7% complete response (CR), 69.1% vs. 58.8% partial response (PR), 4.4% vs. 1.5% stable disease (SD). The best response to PARPi according to median Ki67 was 19.1% vs. 36.8% CR, 26.5% vs. 26.5% PR, 26.5 vs. 25% SD, 27.9% vs. 16.2% progressive disease (PD). No statistically significant differences in progression free survival (PFS) and overall survival (OS) were identified between low and high Ki67. PFS and OS are in line with registration trials. CONCLUSIONS: Ki67 at diagnosis did not discriminate responders to PARPi.

Prescribing pattern of anticoagulants in patients with cancer associated thrombosis: Results of a survey among MITO group and AIOM society.

INTRODUCTION: Low molecular weight heparin (LMWH) has been the backbone of the treatment of cancer associated thrombosis (CAT). Direct-acting oral anticoagulants (DOACs) have shown efficacy and safety not inferior to LMWH and guidelines included DOACs as an option for CAT treatment. Nevertheless, DOACs are still poorly prescribed in patients with cancer. The aim of this survey was to better understand prescription patterns of anticoagulants, in particular of DOACs, especially in gynecological cancers (GCs). METHODS: Our survey was made up of 21 questions, the last four questions addressed to medical doctors (MDs) involved in GCs. An invitation to complete the survey was sent by e-mail to 691 MITO (Multicentre Italian Trials in Ovarian cancer and gynaecologic malignancies) and 2093 AIOM (Associazione Italiana di Oncologia Medica) members. RESULTS: Overall, 113 MDs completed the questionnaire, 69 involved in GCs. Most respondents (46, 41%) were aged 30-40 years old, worked in public hospitals (59, 52.2%), were medical oncologists (86, 76.1%). LMWH was the preferred choice for the treatment of CAT (104, 92%). However, 89 respondents (78.8%) prescribed or asked to prescribe a DOAC for CAT. The major concern about DOACs was the difficulty in verifying the therapeutic effect and the absence of antidotes in case of bleeding (37.9%). In patients with GCs, DOACs were used with niraparib, olaparib, rucaparib and immune checkpoint inhibitors (ICIs) in less than 10 patients by 23%, 20%, 9% and 10.2% of respondents, respectively. CONCLUSION: The responders are aware of the Direct-acting oral anticoagulants option and would like to use them.

Corrigendum: Management of metastatic endometrial cancer: physicians' choices beyond the first line after approval of checkpoint inhibitors.

[This corrects the article DOI: 10.3389/fonc.2023.1247291.].

MITO39: Efficacy and Tolerability of Pegylated Liposomal Doxorubicin (PLD)-Trabectedin in the Treatment of Relapsed Ovarian Cancer after Maintenance Therapy with PARP Inhibitors-A Multicenter Italian Trial in Ovarian Cancer Observational Case-Control Study.

OBJECTIVE: While PLD-Trabectedin is an approved treatment for relapsed platinum-sensitive ovarian cancer, its efficacy and tolerability has so far not been tested extensively in patients who progress after poly ADP-ribose polymerase inhibitor (PARPi) treatment. METHODOLOGY: This multicenter, retrospective analysis had the objective of comparing patients receiving PLD-Trabectedin after being treated with PARP-I (cases) with PARPi-naïve patients. Descriptive and survival analyses were performed for each group. RESULTS: Data from 166 patients were collected, composed of 109 cases and 57 controls. In total, 135 patients were included in our analyses, composing 46 controls and 89 cases. The median PFS was 11 months (95% IC 10-12) in the control group vs. 8 months (95% IC 6-9) in the case group (p value 0.0017). The clinical benefit rate was evaluated, with an HR for progression of 2.55 (1.28-5.06) for the case group (p value 0.008), persisting when adjusted for BRCA and line with treatment. We compared hematological toxicity, gastro-intestinal toxicity, hand-foot syndrome (HFS), fatigue, and liver toxicity, and no statistically significant disparity was noted, except for HFS with a p value of 0.006. The distribution of G3 and G4 toxicities was also equally represented. CONCLUSION: The MITO39 study showed a statistically significant difference in terms of PFS, suggesting that previous exposure to PARPi might inhibit the efficacy of PLD-Trabectedin. Regarding tolerability, no remarkable disparity was noted; PLD-Trabectedin was confirmed to be a well-tolerated scheme in both groups. To our knowledge, these are the first data regarding this topic, which we deem to be of great relevance in the current landscape.

Pembrolizumab as a single agent for patients with MSI-H advanced endometrial carcinoma.

INTRODUCTION: Endometrial cancer can be characterized by high instability of microsatellites (MSI-H), a biomarker indicative of sensibility to immune checkpoint inhibitors (ICIs). The results of the KEYNOTE-158 trial led to the approval of pembrolizumab - a monoclonal, humanized IgG4 kappa anti-PD-1 antibody able to prevent T-cell PD-1/tumor cell PD-L1/2 interaction, thus restoring T-cell-mediated anti-tumor immunity - in MSI-H endometrial cancer relapsing after at least one line of chemotherapy (CT). AREAS COVERED: Ongoing trials, such as KEYNOTE-B21/ENGOT-en11, KEYNOTE-C93/ENGOT-en15/GOG-3064, and NRG/GY018, aim to move this option earlier in the algorithm, whether adjuvant or first-line, even CT-free. Combinatorial approaches associating ICIs with other target therapies blocking immunosuppressive pathways are also being studied. EXPERT OPINION: The ICI overall response rates in MSI-H patients are encouraging, but over 50% do not respond to treatment. A more thorough definition of the MSI status regarding specific missing proteins could allow better use of this biomarker and explain why specific populations may not respond to immunotherapy regardless of widely accepted predictive biomarkers. Future developments should focus on identifying who can benefit from a CT-free treatment and translational research on primary resistant MSI-H EC.

Clinical and Histopathological Predictors of Recurrence in Uterine Smooth Muscle Tumor of Uncertain Malignant Potential (STUMP): A Multicenter Retrospective Cohort Study of Tertiary Centers.

BACKGROUND: The term uterine smooth muscle tumor of uncertain malignant potential (STUMP) indicates a rare, equivocal entity between benign leiomyomas and leiomyosarcomas. In the present study, we evaluated a comprehensive range of clinical, surgical, and pathological features in a large multicenter series of patients with STUMP to identify risk factors for recurrence. METHODS: This is a retrospective study performed by collecting consecutive cases diagnosed between January 2000 and December 2020 in five tertiary centers. Associations between STUMP recurrence and clinicopathological characteristics as well as surgical treatment modality were investigated. RESULTS: Eighty-seven patients affected by STUMP were considered. Of them, 18 cases (20.7%) recurred: 11 as leiomyosarcoma (LMS) and 7 as STUMP. The mean time to recurrence was 79 months. We found that fragmentation/morcellation, epithelioid features, high mitotic count, Ki-67 value > 20%, progesterone receptor (PR) < 83%, and p16 diffuse expression were associated with higher risk of recurrence and shorter recurrence-free survival (RFS). Furthermore, morcellation/fragmentation and mitotic count remained independent risk factors for recurrence and shorter RFS after multivariate analysis, while the presence of epithelioid features was an independent risk factor for recurrence only. CONCLUSIONS: Our results suggest that morcellation is associated with risk of recurrence and shorter RFS, thus it should be avoided if a STUMP is suspected preoperatively. Epithelioid features, high proliferation activity, low PR expression, and diffuse p16 expression are also unfavorable prognostic factors, so patients presenting these features should be closely followed up.

Management of Metastatic Endometrial Cancer: Physicians' Choices Beyond the First Line. A MITO Survey.

Background: Endometrial cancer (EC) therapeutic and diagnostic approaches have been changed by the development of a new prognostic molecular classification, the introduction of dostarlimab in microsatellite instability (MSI) high pre-treated advanced EC patients with further expected innovation deriving from lenvatinib plus pembrolizumab regardless MSI status. How this is and will be translated and embedded in the clinical setting in Italy is not known; this is why we developed Multicentre Italian Trials in Ovarian cancer and gynaecologic malignancies (MITO) survey on the current practice and expected future changes in EC. Methods: We designed a self-administered, multiple-choice online questionnaire available only for MITO members for one month, starting in April 2021. Results: 75.6% of the respondents were oncologists with a specific focus on gynaecologic malignancies and 73.3% of the respondents declared the availability of clinical trials in second line treatment for advanced EC. The therapeutic algorithm in second line was heterogeneous, being the most frequent choice administering anthracyclines followed by endocrine therapy or enrolling in clinical trials. While more than half of the clinicians declared that they performed the molecular classification, only six/45 respondents (13.3%) ran all the tests needed for it. On the other hand, 80% of them declared regular assessment of MSI status with IHC as recommended. The therapeutic approach in MSI high advanced EC patients has changed since dostarlimab approval. Indeed the most frequent choice in second line has been chemotherapy (53.3%) before its availability, while dostarlimab has been preferred in more than three-fourths of the cases (75.6%) after its approval. As for MSS patients, 77.8% of clinicians would choose lenvatinib plus pembrolizumab for them in second line once approved. Conclusions: Despite the selected sample of respondents from Italian MITO centres showing good knowledge of diagnostic and therapeutic innovations in EC, these are not fully implemented in everyday clinics, except for MSI status assessment.

Immunotherapy for Cervical Cancer: Are We Ready for Prime Time?

The prognosis of invasive cervical cancer (CC) remains poor, with a treatment approach that has remained the same for several decades. Lately, a better understanding of the interactions between the disease and the host immune system has allowed researchers to focus on the employment of immune therapy in various clinical settings. The most advanced strategy is immune checkpoint inhibitors (ICIs) with numerous phase II and III trials recently concluded with very encouraging results, assessing single agent therapy, combinations with chemotherapy and radiotherapy. Apart from ICIs, several other compounds have gained the spotlight. Tumor Infiltrating Lymphocytes (TILs) due to their highly selective tumoricidal effect and manageable adverse effect profile have received the FDA's Breakthrough Therapy designation in 2019. The antibody drug conjugate (ADC) Tisotumab-Vedotin has shown activity in metastatic CC relapsed after at least one line of chemotherapy, with a phase III trial currently actively enrolling patients. Moreover, the deeper understanding of the ever-changing immune landscape of CC carcinogenesis has resulted in the development of active therapeutic vaccines. This review highlights the different immunotherapeutic strategies being explored reflects on what role immunotherapy might have in therapeutic algorithms of CC and addresses the role of predictive biomarkers.

Biomarkers of Central Nervous System Involvement from Epithelial Ovarian Cancer.

Epithelial ovarian cancer (EOC) is the leading cause of death among women affected by gynaecological malignancies. Most patients show advanced disease at diagnosis (FIGO stage III-IV) and, despite the introduction of new therapeutic options, most women experience relapses. In most cases, recurrence is abdominal-pelvic; however, EOC can occasionally metastasize to distant organs, including the central nervous system. The incidence of brain metastases (BMs) from EOC is low, but it has grown over time; currently, there are no follow-up strategies available. In the last decade, a few biomarkers able to predict the risk of developing BMs from OC or as potential therapeutic targets have been investigated by several authors; to date, none have entered clinical practice. The purpose of this review is to offer a summary on the role of the most relevant predictors of central nervous system (CNS) involvement (hormone receptors; BRCA; MRD1; PD-1/PD-L1) and to highlight possible therapeutic strategies for the management of metastatic brain disease in EOC.

The Role of PARP Inhibitors in the Ovarian Cancer Microenvironment: Moving Forward From Synthetic Lethality.

PARP inhibitors (PARPi) have shown promising clinical results and have revolutionized the landscape of ovarian cancer management in the last few years. While the core mechanism of action of these drugs has been largely analyzed, the interaction between PARP inhibitors and the microenvironment has been scarcely researched so far. Recent data shows a variety of mechanism through which PARPi might influence the tumor microenvironment and especially the immune system response, that might even partly be the reason behind PARPi efficacy. One of many pathways that are affected is the cGAS-cGAMP-STING; the upregulation of STING (stimulator of interferon genes), produces more Interferon ϒ and pro inflammatory cytokines, thus increasing intratumoral CD4+ and CD8+ T cells. Upregulation of immune checkpoints such as PD1-PDL1 has also been observed. Another interesting mechanism of interaction between PARPi and microenvironment is the ability of PARPi to kill hypoxic cells, as these cells show an intrinsic reduction in the expression and function of the proteins involved in HR. This process has been defined "contextual synthetic lethality". Despite ovarian cancer having always been considered a poor responder to immune therapy, data is now shedding a new light on the matter. First, OC is much more heterogenous than previously thought, therefore it is fundamental to select predictive biomarkers for target therapies. While single agent therapies have not yielded significant results on the long term, influencing the immune system and the tumor microenvironment via the concomitant use of PARPi and other target therapies might be a more successful approach.

Cytoreductive Surgery for Heavily Pre-Treated, Platinum-Resistant Epithelial Ovarian Carcinoma: A Two-Center Retrospective Experience.

Few retrospective studies have shown a benefit in selected patients affected by heavily pre-treated, platinum-resistant ovarian carcinomas (PROCs) who have undergone cytoreduction at relapse. However, the role of tertiary and quaternary cytoreductive surgery is not fully defined. Our aim was to evaluate survival and surgical morbidity and mortality after maximal cytoreduction in this setting. We evaluated all consecutive patients undergoing cytoreduction for platinum-resistance over an 8-year period (2010-2018) in two different centers. Fifty patients (median age 52.5 years, range 34-75) were included; the median number of previous chemotherapy lines was three (range 1-7) and the median number of previous surgeries was one (range 1-4). Completeness of cytoreduction (CC = 0) was achieved in 22 patients (44%). Rates of major operative morbidity and 30-day mortality were 38% and 8%, respectively. Median follow-up was 35 months. The absence of tumor residual (CC = 0) was associated with a significantly better overall survival (OS) compared to the CC > 0 subgroup (median OS 32.9 months (95% CI 21.6-44.2) vs. 4.8 months (95% CI n.a.-9.8), hazard ratio (HR) 4.21 (95% CI 2.07-8.60), p < 0.001). Optimal cytoreduction is feasible and associated with promising OS in selected, heavily pre-treated PROCs. Further prospective studies are required to better define the role of surgery in platinum-resistant disease.

Immuno-Metabolism and Microenvironment in Cancer: Key Players for Immunotherapy.

Immune checkpoint inhibitors (ICIs) have changed therapeutic algorithms in several malignancies, although intrinsic and secondary resistance is still an issue. In this context, the dysregulation of immuno-metabolism plays a leading role both in the tumor microenvironment (TME) and at the host level. In this review, we summarize the most important immune-metabolic factors and how they could be exploited therapeutically. At the cellular level, an increased concentration of extracellular adenosine as well as the depletion of tryptophan and uncontrolled activation of the PI3K/AKT pathway induces an immune-tolerant TME, reducing the response to ICIs. Moreover, aberrant angiogenesis induces a hypoxic environment by recruiting VEGF, Treg cells and immune-suppressive tumor associated macrophages (TAMs). On the other hand, factors such as gender and body mass index seem to affect the response to ICIs, while the microbiome composition (and its alterations) modulates both the response and the development of immune-related adverse events. Exploiting these complex mechanisms is the next goal in immunotherapy. The most successful strategy to date has been the combination of antiangiogenic drugs and ICIs, which prolonged the survival of patients with non-small-cell lung cancer (NSCLC) and hepatocellular carcinoma (HCC), while results from tryptophan pathway inhibition studies are inconclusive. New exciting strategies include targeting the adenosine pathway, TAMs and the microbiota with fecal microbiome transplantation.