Alessandra Anna Prete

Background: Biliary tract cancers (BTCs) are aggressive malignancies with limited treatment options. The addition of durvalumab or pembrolizumab to cisplatin–gemcitabine improves overall survival (OS), but validated biomarkers of benefit remain limited. Immune-mediated adverse events (imAEs) have been proposed as treatment-emergent clinical correlates of immune activation. Methods: We retrospectively analyzed an international cohort of patients with locally advanced or metastatic BTC treated with first-line cisplatin–gemcitabine plus durvalumab. Primary endpoints were OS and progression-free survival (PFS). The principal exposure was the occurrence of any imAE. A post hoc complete-case Cox model was adjusted for age, sex, primary tumor site, prior surgery, ECOG performance status, disease stage, albumin, bilirubin, and neutrophil-to-lymphocyte ratio (NLR); analyses of individual AEs were exploratory. Exact AE onset dates were not consistently available, precluding a reliable formal time-dependent exposure analysis. Results: A total of 1358 patients were included; all received durvalumab, and 276 (20.3%) developed at least one imAE. In the fully baseline-adjusted model, any imAE remained associated with a lower risk of death (adjusted HR 0.72, 95% CI 0.57–0.92; p = 0.008) and progression or death (adjusted HR 0.63, 95% CI 0.52–0.77; p < 0.001). In exploratory baseline-adjusted analyses of individual imAEs, other imAEs remained associated with OS (HR 0.39, 95% CI 0.24–0.62; p < 0.001) and PFS (HR 0.56, 95% CI 0.40–0.77; p < 0.001), while hypothyroidism remained associated with PFS only (HR 0.65, 95% CI 0.43–0.97; p = 0.034); rash and hyperthyroidism were not independently associated after full baseline adjustment. In AE-focused exploratory models, decreased appetite and hyponatremia were associated with worse outcomes, neutropenia with better outcomes, and ALT elevation with worse PFS. Baseline corticosteroid use was uncommon (n = 21), and all steroid analyses are vulnerable to confounding by indication and exposure-timing bias. Conclusions: Treatment-emergent imAEs may represent potential prognostic markers or clinical correlates of benefit, but they are not validated surrogate endpoints. Prospective studies with precise AE-onset capture are required.

Background: Rectal cancer management involves surgery, chemotherapy (CT), radiotherapy (RT), and patient care strategies, all of which significantly affect health-related quality of life (HRQoL). Understanding these effects is critical for optimizing treatment protocols. This review aimed to systematically analyze the impact of rectal cancer treatment on HRQoL. Methods: Four databases, Scopus, EMBASE, MEDLINE, and the Cochrane Central Register of Controlled Trials, were searched for randomized controlled trials (RCTs) published between January 2013 and December 2023. RCTs specifically focusing on rectal cancer treatments (surgical interventions, pre- and/or post-CT and/or RT, and patient care strategies) were included. An abstract review, data extraction, and a risk-of-bias assessment were independently conducted by two reviewers. Results: The 41 included studies comprised 9240 patients: 16 evaluated surgical interventions (3507 patients), 15 evaluated pre- and/or post-CT and/or RT protocols (5114 patients), and 10 focused on patient-care strategies (619 patients). Sphincter-sparing procedures were associated with better HRQoL than abdominoperineal resection, and rectal-sparing techniques were associated with better overall HRQoL than rectal resection. RT was associated with a poorer HRQoL. Continuity-of-care interventions improved HRQoL in ostomy patients, whereas transanal irrigation improved HRQoL after ostomy closure. Conclusions: This systematic review of RCTs underscores the importance of organ-sparing strategies, such as rectum-sparing approaches and continuity-of-care packages, in improving HRQoL in patients with rectal cancer. Although RT negatively affects HRQoL, treatment regimens should be individualized. Tailored organ-preservation approaches and structured follow-up care are essential for optimizing HRQoL in patients with rectal cancer.

Background: The aim of this study is to evaluate the correlation between body mass index (BMI) and body fat composition (measured with radiological fat parameters (RFP)) and pathological response after neoadjuvant chemoradiotherapy for locally advanced rectal cancer patients. The secondary aim of the study was to assess the role of BMI and RFP on major surgical complications, overall survival (OS), and disease-free survival (DFS).Methods: All patients who underwent surgical resection following nCRT between 2005 and 2017 for mid-low rectal cancer were retrospectively collected. Visceral fat area (VFA), superficial fat area (SFA), visceral/superficial fat area ratio (V/S), perinephric fat thickness (PNF), and waist circumference (WC) were estimated by baseline CT scan. Predictors of pathologic response and postoperative complications were investigated using logistic regression analysis. The correlations between BMI and radiologic fat parameters and survival were investigated using the Kaplan–Meier method and log-rank test.Results: Out of 144 patients included, a complete (TRG1) and major (TRG1+2) pathologic response was reported in 32 (22%) and 60 (45.5%) cases, respectively. A statistically significant correlation between BMI and all the RFP was found. At a median follow-up of 60 (35–103) months, no differences in terms of OS and DFS were found considering BMI and radiologic fat parameters. At univariable analysis, neither BMI nor radiologic fat parameters were predictors of complete or major pathologic response; nevertheless, VFA, V/S>1, and BMI were predictors of postoperative major complications.Conclusions: We found no associations between BMI and body fat composition and pathological response to nCRT, although VFA, V/S, and BMI were predictors of major complications. BMI and RFP are not related to worse long-term OS and DFS.

5 Background: Advanced squamous cell anal cancer (aSCAC) is a rare and aggressive disease, accounting for poor prognosis and high morbidity. No targeted therapies are currently available and, after the first line, no standard treatments are approved. Immune checkpoint inhibitors (ICI) showed signs of activity in previous phase I/II trials, but predictive and prognostic biomarkers are lacking. Anti-EGFR have been tested given the rarity of KRAS mutations in aSCAC, with encouraging results. Earlier preclinical evidence suggests possible synergism between cetuximab (cet) and ICI. Methods: In the phase II randomized trial CARACAS (NCT03944252), we tested avelumab (ave) alone (Arm A) or with cet (Arm B) in pretreated aSCAC; overall response rate (ORR) was the primary endpoint. With one-sided a error set at 0.05 and power of 80%, at least 4 responses out of 27 patients (pts) per arm had to be observed to declare the study positive. On pre-treatment tumor tissue samples, we assessed HPV status, PD-L1 expression, microsatellite status, tumor mutational burden (TMB) and performed next generation sequencing (NGS) via FoundationOne CDx. Primary objective was to describe the clinical outcomes of ICI in SCAC in the CARACAS trial population according to molecular analyses. Secondary objectives were to assess progression-free survival (PFS) and overall survival (OS) according to molecular characteristics to individuate new prognostic biomarkers in SCAC. Cox regression was used to investigate the effect of the main variables analysed on survival. Translational analyses were performed on the 100% of the study population since all the pts received ICI. Results: In the clinical trial, the Arm B reached the primary endpoint (ORR 17%, 95% CI 5·6-34·7). High TMB (≥10 mutations per megabase) was related with longer OS (HR=0.09; 95% CI 0.01-0.68; p=0.019), showing the same trend in PFS (HR=0.44; 95%CI=0.15-1.27; p=0.129). As well, tumors with high expression of PD-L1 (>40 measured with combined positive score, CPS) showed significantly longer OS (HR=2.19; 95% CI=0.92-5.19; p=0.075) and PFS (HR=2.35; 95%CI=1.09-5.1; p=0.03). High TILs (>1.2) did not affect significantly OS (HR=0.77; 95% CI=0.42-1.4; p=0.39) nor PFS (HR=1.19; 95%CI=0.57-2.48; p=0.645). When combined together and with high TILs, high TMB and PD-L1identified pts with significantly better prognosis in OS (HR=0.43; 95% CI=0.21-0.87; p=0.019) and PFS (HR=0.48; 95%CI=0.23-1.00; p=0.051). Remarkable responses were also observed in pts with high PD-L1 expression and TMB. Conclusions: TranslaCARACAS study documented prognostic role of high TMB and PD-L1 in mSCAC treated with ICI with or without anti-EGFR. Stratifying per high TMB, PD-L1 and TILs, a subgroup of pts with particularly favorable prognosis and deep responses were detected. Further investigation in larger cohorts is warranted to confirm our findings.

PARP inhibitors are largely recognized as active drugs in BRCA-mutated breast and ovarian malignancies. In pancreatic ductal adenocarcinoma, the PARP inhibitor olaparib has recently been approved as maintenance treatment in patients with germline BRCA mutations reaching disease control after a platinum-based first line chemotherapy, proving significant benefit on progression free survival. On the other hand, little evidence is available regarding olaparib as single agent after progression with standard treatment in BRCA-mutated pancreatic ductal adenocarcinoma. A 61-year-old female patient harboring germline BRCA2 mutation was treated at our institution for a pancreatic ductal adenocarcinoma with lung and liver metastases. The patient received three previous lines of treatment with standard therapies, as follows: after the third line treatment failure, we started a further line of treatment with olaparib in off-label prescription. After the first two cycles, a CT scan documented partial response, with complete regression of lung metastases. The response was maintained after four cycles, with further response and clinical benefit. The radiologic and clinical response was maintained for 6 months. This case highlights the potential of olaparib as single agent after progression with standard treatment in BRCA-mutated pancreatic cancer.

4051 Background: Advanced squamous cell anal carcinoma (advSCAC) is a rare disease with poor prognosis. No standard therapies beyond first line are currently available, yet a promising activity was documented for the anti-EGFR cetuximab (CET) and for anti-PD-1 agents in previous retrospective case series and phase I-II studies, respectively. In experimental models combination of EGFR and PD-L1 blockade was synergistic as PD-L1 blockade led to NK cells activation enhancing cetuximab ADCC. In this trial we aimed to evaluate safety and activity of the anti-PD-L1 avelumab (AVE) alone or in combination with CET in pretreated advSCAC. Methods: This was an open-label, prospective, multicenter randomized phase 2 trial (NCT03944252). Patients (pts) with advSCAC progressed after at least 1 line of treatment were randomized 1:1 to receive either AVE 10 mg/kg (arm A) or AVE + CET 500 mg/sqm (arm B) as bi-weekly regimens. A Simon’s two-stage Mini-Max design was used. The null hypothesis of a true response rate 5% was tested against the one-sided alternative of a true response rate 20% in each arm. Setting type I error at 0.05 and power at 80%, 30 pts per arm had to be randomized. No formal comparison between the two arms was planned. Primary endpoint was overall response rate (ORR); secondary endpoints were Progression-Free Survival (PFS), Overall Survival (OS) and safety. Results: Sixty pts were enrolled, 30 in each arm. All baseline characteristics were well balanced between the two arms. Median age was 63 years; M/F was 19/41; 12 out of 30 pts in each arm had distant metastases; 7 in arm A and 10 in arm B received > 1 previous lines of treatment. At a median follow up of 8.7 months, 3 out of 30 pts in each arm obtained PR (ORR 10%); SD was observed in 12 pts in arm A (40%) and 14 in arm B (47%). Disease control rate was thus 50% in arm A and 57% in arm B. Duration of disease control was 6.1 (95%CI 3.7–11.0) and 6.1 (95%CI 4.1–9.6) months in arm A and B, respectively. Median PFS was 2.1 (95%CI 1.8–4.0) in arm A and 3.9 months (95%CI 2.1–5.6) in arm B. Grade 3-4 adverse events were 13.3% in arm A and 33.3% in arm B: anemia 10% vs 13.3%, fatigue 0 vs 6.7%, skin toxicity 0 vs 6.7%. Treatment interruption due to AE occurred in 3 pts, 1 in arm A and 2 in arm B. Translational analyses will be performed on tissue and blood samples for exploratory purpose. Conclusions: The CARACAS trial was the first clinical study to test dual EGFR and PD-L1 blockade in advSCAC. Both AVE monotherapy and AVE-CET showed promising activity with manageable safety profile. Clinical trial information: NCT03944252.

Immune inflammation indicators in anal cancer patients treated with concurrent chemoradiation: training and validation cohort with online calculator (ARC: Anal Cancer Response Classifier) [Corrigendum]