323 Background: A positive family history is a well-established risk factor for prostate cancer (PCa), making the identification of individuals with inherited susceptibility particularly relevant. The detection of germline pathogenic variants (PVs) in DNA-repair genes (DRGs) further supports the implementation of targeted screening strategies. The present study aimed to investigate the performance and adherence of a personalized screening protocol designed for this high-risk population, integrating both the Prostate Health Index (PHI) and multiparametric magnetic resonance imaging (mpMRI). Methods: This ongoing prospective study, supported by AIRC-(ID-IG-25027-V1.3), is based on the concept of a dedicated PCa screening protocol. It was conducted at a tertiary referral center in collaboration with multiple departments. The study enrolled men aged 35–69 years carrying documented PVs in DRGs who provided informed consent to participate in the screening program. Probands were classified into two groups: (1) male relatives of women harboring DRG PVs associated with breast or ovarian cancer, and (2) male relatives of men with DRG PVs diagnosed with high-grade PCa (ISUP grade group >2). Participants underwent annual assessments including PSA testing, PHI measurement, DRE, and mpMRI, according to individual risk stratification (PHI <20, 20–40, >40). Results: Between 2021 and 2025, a total of 129 patients were enrolled, with a median age of 52 years (IQR 47–64). Among them, 118 belonged to the group 1 and 11 to the group 2. The most prevalent PVs was BRCA2 (56.0%), followed by BRCA1 (21.6%), ATM (3.4%), PMS2 (2.6%), MSH2 (2.6%), MLH1 (2.6%), PALB2 (2.6%), and MSH6 (1.7%). Screening compliance was high: 95% of participants completed the T1 visit, 86% completed T2, 90% completed T3, and 100% completed T4. Among patients with PHI values between 20 and 40, 85% underwent mpMRI. Three of these showed a positive mpMRI and proceeded to biopsy, which was negative two cases and positive in one. An additional 3 patients underwent biopsy due to clinical suspicion, all yielding negative results. Among those with PHI >40, 75.5% underwent mpMRI followed by biopsy according to protocol, all of which were negative for prostate cancer. At the fourth year of follow-up, the screening program detected its first case of PCa: a BRCA2 carrier with a PVs, whose biopsy confirmed ISUP 4 PCa. The patient has been scheduled for surgery. Conclusions: The screening program detected the first case of PCa in a 57-year-old man. Despite this finding, the overall incidence of PCa in our cohort remains notably lower than reported in international studies, including the IMPACT trial. This unexpected result may suggest the presence of a population-specific protective factor, a phenomenon we refer to as the “Italian paradox.” Nevertheless, given the limited sample size and short follow-up, this observation should be interpreted cautiously.

321 Background: Family history represents a significant risk factor for prostate cancer (PCa), emphasizing its genetic basis. Early identification of germline pathogenic variants (PVs) in DNA repair genes (DRGs) is crucial for timely PCa diagnosis, prognosis, and for informing at-risk relatives. Conversely, the presence of variants of uncertain significance (VUS) has been associated with worse clinical outcomes. This study aimed to assess how the presence of germline PVs and VUS affect clinical and pathological outcomes in a monocentric cohort of patients who underwent robot-assisted laparoscopic prostatectomy (RALP) for PCa. Methods: This prospective study, supported by AIRC - Fondazione AIRC per la Ricerca sul Cancro (registered and emended with the number ID-IG-25027-V1.3), was conducted at a tertiary referral center in collaboration with the Departments of Oncology, Urology, Pathology, Radiology, and Medical Genetics. A total of 179 men aged 58–70 years who underwent RALP for localized PCa were screened for germline PVs and VUS in DRGs prior to surgery. Patients were enrolled if they had an ISUP grade ≥3 at biopsy and/or a confirmed PCa diagnosis at ≤50 years of age. Individuals harboring a VUS or PVs were compared to those with negative genetic results. Results: Of the 179 patients screened between 2021 and 2024, 163 shared the results of genetic testing. Median age at surgery did not differ between groups (65 years, IQR 59–70). Among them, 114 (69.9%) tested negative, while 39 (29.4%) and 9 (5%) carried a VUS or PVs in DRGs, respectively. The most frequent VUS involved ATM (22.2%), CHEK2 (15.6%), BRCA2 (13.3%), ATR (6.7%), NBN (6.7%), RAD51D (6.7%), and MSH6 (4.4%). The nine PVs identified were: BRCA2, PALB2 + NBN, PALB2 + BRCA2, BRCA1 PALB2, CHEK2 + PMS2, CHEK2, and ATM . A family history of cancer was reported in 50% of VUS/PV carriers compared to 34.6% of non-carriers. High-grade PCa (ISUP >3) was found in 46.3% of carriers versus 38.0% of non-carriers. A pathological stage ≥pT3a occurred in 53.6% of carriers versus 45.1% of non-carriers, while nodal involvement (pN1) was more frequent among carriers (21.4% vs 12.6%). Biochemical recurrence (BCR) occurred in 36.8% of carriers versus 30.4% of non-carriers. Conclusions: This study provides valuable insight into the role of germline VUS, by the first, and PVs in DRGs among PCa patients, suggesting that such variants may confer a less favorable disease course. Although differences did not reach statistical significance, carriers tended to present with higher-grade and more advanced disease at final pathology. Genetic screening for PCa may therefore aid not only in early detection among high-risk individuals but also in guiding clinical management and follow-up strategies.

This prospective imaging trial was designed to compare [68Ga]PSMA-11 PET/CT with multiparametric MRI (mpMRI) in parallel in men with suspicion of prostate cancer (PCa) after at least one previous negative biopsy (ClinicalTrials.gov: NCT05297162; GR-2018-12366240). Between April 2022 and June 2025, we enrolled 130 patients who met the inclusion criteria and completed protocol investigations. Target lesions were defined based on PI-RADS v2.1 for mpMRI and PRIMARY Score, SUVmax and SUVratio for [68Ga]PSMA-11 PET/CT. Findings were statistically correlated with pathology results. Subsequently, we developed a nomogram to predict clinically significant PCa (csPCa), defined as International Society of Urological Pathology [ISUP] grade ≥ 2, using Boruta’s algorithm for variable selection. Median age in our cohort was 65.5 years (range, 50.5–82.2) and median PSA 9.7 ng/ml (range, 4–35). According to pathology, 20 patients (15.4

Background and Objective: Transurethral resection of bladder tumor (TURBT) is the standard for non-muscle-invasive bladder cancer (NMIBC), yet recurrence rates remain high. This study evaluates the safety, tolerability, and efficacy of neoadjuvant intravesical mitomycin C (neoMMC) before TURBT in reducing recurrence and improving surgical outcomes. Methods: This randomized phase III trial enrolled patients with primary or recurrent NMIBC. Participants were randomized 1:1 to a neoadjuvant group receiving two instillations of MMC (day -14 and -7) before TURBT, or a control group undergoing standard TURBT without neoadjuvant treatment. The primary endpoint was 12-month recurrence-free survival (RFS). Secondary endpoints included surgical quality (complete resection, cauterization only, absence of residual tumor) and safety. Exploratory endpoints included histopathologic response and time to recurrence. Key Findings and Limitations: Among 95 patients (48 neoMMC, 47 controls), baseline characteristics were balanced. After a median follow-up of 19.4 months, recurrences occurred in 9 StA and 4 NeoA patients, with one progression to MIBC in the NeoA arm. RFS did not differ significantly between groups at 12 or 18 months. Neoadjuvant MMC was well tolerated, with only grade 1-2 AEs. Exploratory microbiota analyses suggested that neoadjuvant MMC modulated urinary microbial diversity and was associated with a microbiota profile more similar to that observed in non-recurrent patients. Limitations include single-center design and relatively short follow-up. Conclusions and Clinical Implications: Neoadjuvant intravesical MMC before TURBT was feasible and well tolerated in patients with NMIBC, with no unexpected safety signals. In this prematurely terminated and underpowered trial, no significant improvement in RFS was observed. Larger adequately powered studies are needed to clarify the oncologic efficacy of this approach.

BACKGROUND Nodular histiocytic/mesothelial hyperplasia (NHMH) is a rare, benign lesion characterized by a proliferation of histiocytes and mesothelial cells displaying a biphasic architectural pattern. First described by Rosai in the 70s, it may closely mimic malignant processes, particularly within the abdominal cavity. NHMH may be indistinguishable from carcinomatosis intraoperatively, potentially altering surgical management. Because nodules typically measure only a few millimeters, their macroscopic appearance and epithelioid features of cell proliferations histologically can closely resemble metastatic implants, particularly during intraoperative frozen section examination. Recognition of this entity is therefore essential to prevent diagnostic errors and unnecessary interventions. CASE SUMMARY We report the case of a 57-year-old woman in whom NHMH was incidentally identified during exploratory laparoscopy performed for staging metastatic gastric adenocarcinoma. Multiple small peritoneal nodules (2-5 mm) mimicked carcinomatosis intraoperatively. Frozen section examination interpretation was challenging due to the presence of epithelioid cell clusters with stromal desmoplasia that, together with surface irregularity, suggested metastatic implants, creating a high risk of overcalling carcinoma. Final histopathology demonstrated the coexistence of metastatic gastric adenocarcinoma and NHMH. Immunohistochemistry revealed CD68 positivity in histiocytes, calretinin and WT-1 expression in mesothelial cells, thus confirming the diagnosis. CONCLUSION NHMH must be considered in the differential diagnosis of peritoneal nodules identified during staging surgery. Frozen section analysis alone is insufficient and correlation with permanent sections and immunohistochemistry is essential to avoid misdiagnosis and overtreatment during intraoperative decision-making.

PURPOSE:Controversy exists regarding the association between HFE H63D polymorphism and pancreatic ductal adenocarcinoma (PDAC). This study initially assessed the frequency of H63D in PDAC patients and subsequently investigated correlations between genotype and disease phenotype. EXPERIMENTAL DESIGN:H63D prevalence was determined by genotyping 795 PDAC patients from two retrospective cohorts of unselected (n = 389) or surgically resected (n = 171) individuals, and one prospective cohort of resectable cases (n = 235). Associations between H63D status and clinicopathological variables were retrospectively evaluated in unselected patients and prospectively validated in surgical candidates. The phenotypic impact of H63D carriage was also investigated using a genetically engineered KCH67D murine model and PDAC cell lines. Spatial transcriptomics was applied to human PDAC samples to define genotype-associated microenvironmental and cell-cycle alterations. RESULTS:H63D prevalence was higher in patients with resectable PDAC (37.7%, 37.4%, and 34% across cohorts) than in those with unresectable disease (22.4%) or the general population (24.1%). Despite this, resected H63D carriers had significantly worse outcomes, with the variant emerging as an independent predictor of shorter disease-free survival (p = 0.002). Consequently, KCh67d mice developed earlier, larger tumors with increased metastatic spread. H63D PDAC cells and tumor spatial transcriptomic showed enhanced invasiveness, G1-phase accumulation, and TGFβ-independent EMT activation. CONCLUSIONS:The H63D variant is strongly associated with PDAC resectability and, paradoxically, with a poorer post-surgical outcome. Activation of a TWIST1-dependent EMT program within a G1-enriched cellular context underlies the more aggressive phenotype of H63D PDAC, possibly accounting for the clinical conundrum.

Metabolic renal cell carcinomas (RCC) deficient in succinate dehydrogenase (SDH) or fumarate hydratase (FH) are rare but clinically significant entities formalized in the last WHO classification. Their recognition typically starts from morphology and is corroborated by targeted immunohistochemistry (IHC) and, where appropriate, molecular and germline testing. In routine practice, however, implementation may be uneven. Hence, we conducted a nationwide, web-based survey (made by 25 items) among members of the Italian Study Group of Uropathology (GIUP) to map real-world awareness, diagnostic pathways, and test availability across Italian centers. Twenty-one pathologists responded; 18/21 (85.7

BACKGROUND AND OBJECTIVE:Current European Association of Urology guidelines universally recommend a second transurethral resection (ReTUR) for all T1 non-muscle-invasive bladder cancer (NMIBC) cases. However, ReTUR is an invasive and costly procedure that is often negative for residual disease, and may represent overtreatment in appropriately selected patients who have undergone complete initial TUR. Our aim was to report 2-yr oncological outcomes and confirm the safety of a novel, response-guided strategy with selective ReTUR for patients with T1 NMIBC. METHODS:The prospective, observational, multicenter HuNIRe trial enrolled patients with T1 NMIBC from 2020 to 2024. Patients with complete TUR underwent urine cytology at 3-4 wk and cystoscopy at 4-6 wk. ReTUR was performed only if cytology was positive (Paris system 3-6) or disease was detected on cystoscopy; otherwise, patients proceeded directly to bacillus Calmette-Guérin (BCG) induction therapy. The primary endpoints were 2-yr recurrence-free survival (RFS) and progression-free survival (PFS). Secondary endpoints included comparison of outcomes between the groups with and without ReTUR, and between the overall HuNIRe cohort and a retrospective cohort of patients with T1 NMIBC who underwent routine ReTUR. Kaplan-Meier estimates and the log-rank test were used for survival analysis. KEY FINDINGS AND LIMITATIONS:A total of 90 patients were prospectively enrolled. The protocol successfully avoided ReTUR in 71% (n = 64) of patients, who proceeded directly to BCG therapy. Only 29% (n = 26) of the patients required ReTUR according to early evaluation; importantly, no patient was upstaged to MIBC at ReTUR. After median follow-up of 26 mo, 2-yr survival rates for the entire cohort were 69% for RFS and 91% for PFS. There were no significant differences between the groups with and without ReTUR in RFS (p = 0.9) or PFS (p = 0.6). Oncological outcomes were also comparable between the HuNIRe cohort and a retrospective cohort that underwent routine ReTUR (2-yr RFS: 74% vs 74%; 2-yr PFS: 91% vs 92%). CONCLUSIONS AND CLINICAL IMPLICATIONS:Results from the HuNIRe trial confirm that a risk-adapted approach to ReTUR in selected patients with T1 NMIBC after complete initial TUR is feasible, although oncological outcomes should be interpreted with caution owing to the short follow-up. This strategy spared 71% of patients from ReTUR, and could support a tailored, response-guided approach rather than the blanket guideline recommendation for ReTUR.

Gleason pattern 5 (GP5) prostatic adenocarcinoma (PC) includes distinct morphologies: undifferentiated solid pattern (US), solid and cribriform with necrosis (CN), clusters and cords (CC), and isolated single tumour cells (ISTC). The role of these patterns in the metastatic setting is still poorly understood. We conducted a case-control retrospective histological characterization of two cohorts of ISUP Grade Group 5 PC, one with nodal metastases (N1) and one without (N0), comparing GP5 sub-patterns distribution, from robot-assisted radical prostatectomies with extended lymphadenectomy diagnosed between January 2013 and February 2023. A series of PC distant metastases was also retrieved and analyzed. The different GPs and their percentage were determined in lymph nodes, primary tumours, and distant metastases. A total of 88 PC N1, 70 PC N0, and 51 distant metastases were identified. Among the N1 cohort, GP5 was documented in 28/88 nodal metastases (32

Identification of biomarkers for the hematogenous spreading of cancer cells is of paramount prognostic and therapeutic value. We showed that Plasmalemma Vesicle Associated Protein-1 (PV-1) serves as a marker of increased blood vessel permeability and is an independent predictor of colorectal cancer dissemination. This study investigates whether PV-1 can also act as a prognostic marker for distant metastases in other solid tumors. We analyzed samples from 134 patients: 30 luminal breast cancer (BC), 52 clear cell renal cell carcinoma (ccRCC), and obtained preliminary data from 52 soft tissue sarcomas (STS). A higher frequency of PV-1+ endothelial cells was significantly associated with metastatic progression in luminal BC and ccRCC. Moreover, the frequency of PV-1+ cells emerged as a significant prognostic factor for metastasis-free survival in both luminal BC and ccRCC. Further research is needed to validate PV-1's prognostic utility, as including it at diagnosis may change the management of these patients and should allow stratification for more aggressive therapies or for closer follow-ups to promptly intervene in case of metastases development.

421 Background: Pathogenic variants (PVs) in DNA repair genes (DRG) are linked to a higher risk of aggressive prostate cancer (PCa). Understanding and managing variants of uncertain significance (VUS), however, remains a challenge. This study investigates the prevalence of germline VUS in PCa patients and their potential link to prognosis following robot-assisted radical prostatectomy (RARP), aiming to enhance clinical management and risk stratification. Methods: This is part of an ongoing PCa screening project in the Italian population aimed at identifying men with a genetic predisposition (AIRC - Fondazione AIRC per la Ricerca sul Cancro, IG 2020 ID 25027). Germline DRG variants were identified in men with high-risk PCa or those aged <50 scheduled for RARP. After informed consent, blood samples were collected, and data on age, stage, PSA, ISUP grade, and family history were recorded. Genetic analysis used a multigene panel, classifying VUS and PVs per ACMG/AMP and IARC guidelines. Primary outcome: VUS prevalence; secondary: correlations between VUS and pathological status, biochemical recurrence (BCR), and need for adjuvant therapy. Results: A total of 138 men who underwent RARP were enrolled. The median age was 64 years (IQR 57–68). ISUP grade was 1–2 in 54.0% of patients and 3–5 in 46.0%. Family history of PCa was present in 55%. Median PSA was 7.5 ng/mL (IQR 3.3–9.4). DRG variants were identified in 41 men (29.7%), of whom 34 (82.9%) had VUS and 7 (17.1%) had PVs (3 BRCA2, 1 BRCA1, 2 PALB2, 1 CHEK2). VUS carriers were younger at diagnosis (median 62 vs. 64 years). 25.8% of VUS carriers were node-positive, compared to 13.5% of those with negative DRG (p > 0.05). BCR occurred in 24% of VUS patients vs. 18% of those without DRG variants at nearly 2.5 years of follow-up, but this difference was not statistically significant. No significant differences in ISUP grade or positive margin rates were observed. Conclusions: VUS germline mutations are common in PCa patients undergoing RARP. These mutations appear associated with worse outcomes. Study limitations include a single-center cohort, small sample size, and a predominantly European ancestry population.

Infiltration of macrophages into tumors is a hallmark of cancer progression, and re-educating tumor-associated macrophages (TAMs) toward an antitumor status is a promising immunotherapy strategy. However, the mechanisms through which cancer cells affect macrophage education are unclear, limiting the therapeutic potential of this approach. Here we conducted an unbiased genome-wide CRISPR screen of primary macrophages. Our study confirms the function of known regulators in TAM responses and reveals new insights into the behavior of these cells. We identify olfactory and vomeronasal receptors, or chemosensors, as important drivers of a tumor-supportive macrophage phenotype across multiple cancers. In vivo deletion of selected chemosensors in TAMs resulted in cancer regression and increased infiltration of tumor-reactive CD8+ T cells. In human prostate cancer tissues, palmitic acid bound to olfactory receptor 51E2 (OR51E2) expressed by TAMs, enhancing their protumor phenotype. Spatial lipidomics analysis further confirmed the presence of palmitic acid in close proximity to TAMs in prostate cancer, supporting the function of this lipid mediator in the tumor microenvironment. Overall, these data implicate chemosensors in macrophage sensing of the lipid-enriched milieu and highlight these receptors as possible therapeutic targets for enhancing antitumor immunity.

BACKGROUND AND OBJECTIVE:Different substaging methods have been proposed for risk stratification of T1 non-muscle-invasive bladder cancer; however, no consensus exists. This systematic review and meta-analysis evaluates the prognostic value of various T1 substaging systems. METHODS:A systematic literature search was conducted using the PubMed/Medline, Embase, Scopus, and Web of Science databases to identify reports published until January 2025, following the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. The primary outcomes were disease recurrence and progression. A subgroup analysis evaluated histoanatomical and micrometric substaging within the same population. KEY FINDINGS AND LIMITATIONS:Fifty-seven studies met the inclusion criteria. Muscularis mucosae invasion was associated with progression (hazard ratio [HR]: 2.65, 95% confidence interval [CI]: 1.79-3.92, p < 0.001) but not with recurrence (HR: 1.19, 95% CI: 0.88-1.61, p = 0.3). Micrometric substaging (T1m/T1e, 0.5 mm cutoff) correlated with both recurrence (HR: 2.01, 95% CI: 1.53-2.64, p < 0.001) and progression (HR: 3.33, 95% CI: 2.47-4.49, p < 0.001). Considering the substaging systems applied to the same population, the pooled risk ratio (RR) for T1a versus T1b/c was 0.60 (95% CI: 0.45-0.80, p < 0.001), while the RR for T1m versus T1e was 0.39 (95% CI: 0.29-0.52, p < 0.001). The main limitation was heterogeneity in postsurgery management. CONCLUSIONS AND CLINICAL IMPLICATIONS:Histoanatomical substaging significantly associate with progression but not with recurrence. Micrometric substaging demonstrated an association with both recurrence and progression, potentially enhancing patient stratification. Rete Oncologica Lombarda substaging shows some promising results in stratifying patients. These results may support a global pathological consensus on the optimal T1 substaging system.

803 Background: The primary treatment for non-muscle invasive bladder cancer (NMIBC) is transurethral resection (TUR), often followed by adjuvant intravesical therapies. Given the variable response to intravesical therapy, enhancing its efficacy is critical to reducing recurrence and progression to MIBC. Recent studies have shown that MMC induces immunogenic cell death, suggesting its potential in enhancing the effectiveness of other intravesical therapies, such as BCG, activating acquired immunity. This study aimed to evaluate the safety and efficacy of neoadjuvant MMC in patients with NMIBC. Methods: This is a prospective, phase III randomized clinical trial in patients with primary or recurrent BC who had not received intravesical therapy between May 2022 and June 2024 (EudraCT 2021-003751-42; ICH-013). Patients were randomized 1:1 to either the neoadjuvant MMC arm (neoA) or the standard treatment arm (StA). In the two weeks preceding the scheduled TURBT (day 0), patients in the neoA arm received intravesical MMC (40 mg/40 ml) on days -14 and -7, along with cystoscopy and cold-cup biopsy on day -14. Clinical decisions regarding adjuvant therapy and follow-up (FU) schedules in both groups were based on the tumor histology according the European Association of Urology (EAU) guidelines. The primary endpoint was to evaluate the safety, and efficacy of neoadjuvant MMC in reducing the recurrence rate of BC. Patients with MIBC or pT0 were excluded from survival analyses. Results: A total of 63 patients were included: 31 (49%) in the StA group and 32 (51%) in the neoA group. The groups were homogeneous in clinical and pathological characteristics.In the neoA group, 8 adverse events (AEs) were reported in 5 patients (14%), all mild (Grade 1 and 2). Following TUR, 26 AEs grade 1 and 2 were observed in 16 (50%) patients in the StA group, and 24 AEs in 14 (45%) patients in the neoA group, with no significant differences between the groups (p=0.6).In the neoA group, 16 patients had TaLG, 9 had TaHG, 3 had T1HG, 1 had CIS, and 2 had benign findings. No complete tumor ablation occurred, with only 2 cases showing reduced tumor size. In the StA group, 17 had TaLG, 6 had TaHG, 5 had T1HG, and 3 had T2 tumors. After a median FU of 14.5 months, 5 patients in the StA group and 4 in the neoA group recurred. Only one patient, in the neoA group, progressed to MIBC. The 12-month recurrence-free survival (RFS) was 91% (95% CI: 68-98) in the StA group and 84% (95% CI: 62-94) in the neoA group, with no statistically significant difference between the two groups (log-rank test p=0.8). Conclusions: Neoadjuvant MMC showed a favorable safety and tolerability profile. Although no significant RFS difference was found between the neoA and standard arms, a larger cohort and longer FU are needed for definitive conclusions on MMC's oncological efficacy. The upcoming analysis of the adjuvant BCG subgroup will further clarify MMC's role in enhancing BCG efficacy.