Treatment of patients with BRAFV600E-mutated metastatic colorectal cancer after progression to encorafenib and cetuximab: data from a real-world nationwide dataset

BACKGROUND

Targeted therapy (TT) with encorafenib and cetuximab is the current standard for patients with BRAFV600E-mutated metastatic colorectal cancer (mCRC) who received one or more prior systemic treatments. However, the median progression-free survival (mPFS) is ∼4 months, and little is known about the possibility of administering subsequent therapies, their efficacy, and clinicopathological determinants of outcome.

METHODS

A real-world dataset including patients with BRAFV600E-mutated mCRC treated with TT at 21 Italian centers was retrospectively interrogated. We assessed treatments after progression, attrition rates, and outcomes.

RESULTS

Of the 179 patients included, 85 (47%), 32 (18%), and 7 (4%) received one, two, or three lines of treatment after TT, respectively. Those receiving TT in the second line were more likely to receive at least one subsequent therapy (53%), as compared with those treated with TT in the third line or beyond (30%; P < 0.0001), and achieved longer postprogression survival (PPS), also in a multivariate model (P = 0.0001). Among 62 patients with proficient mismatch repair/microsatellite stable (pMMR/MSS) tumors receiving one or more lines of treatment after second-line TT, combinatory chemotherapy ± anti-vascular endothelial growth factor (anti-VEGF) was associated with longer PFS and PPS as compared with trifluridine-tipiracil or regorafenib (mPFS: 2.6 versus 2.0 months, P = 0.07; PPS: 6.5 versus 4.4 months, P = 0.04).

CONCLUSIONS

Our real-world data suggest that TT should be initiated as soon as possible after the failure of first-line treatment in BRAFV600E-mutated mCRC. Among patients with pMMR/MSS tumors, combinatory chemotherapy ± anti-VEGF appears the preferred treatment choice after TT failure.

Pemigatinib for patients with previously treated, locally advanced or metastatic cholangiocarcinoma harboring FGFR2 fusions or rearrangements: A joint analysis of the French PEMI-BIL and Italian PEMI-REAL cohort studies

BACKGROUND

Pemigatinib is approved for patients with pretreated, locally advanced or metastatic CCA harboring FGFR2 rearrangements or fusions. We aim to assess the effectiveness and safety of pemigatinib in real-world setting.

MATERIAL AND METHODS

A joint analysis of two multicentre observational retrospective cohort studies independently conducted in France and Italy was performed. All consecutive FGFR2-positive patients affected by CCA and treated with pemigatinib as second- or further line of systemic treatment in clinical practice, within or outside the European Expanded Access Program, were included.

RESULTS

Between July 2020 and September 2022, 72 patients were treated with pemigatinib in 14 Italian and 25 French Centres. Patients had a median age of 57 years, 76% were female, 81% had ECOG-PS 0-1, 99% had intrahepatic CCA, 74% had ≥ 2 metastatic sites, 67% had metastatic disease at diagnosis, while 38.8% received ≥ 2 previous lines of systemic treatment. At data cut-off analysis (April 2023), ORR and DCR were 45.8% and 84.7%, respectively. Median DoR was 7 months (IQR: 5.8-9.3). Over a median follow-up time of 19.5 months, median PFS and 1-year PFS rate were 8.7 months and 32.8%. Median OS and 1-year OS rate were 17.1 months and 60.6%. Fatigue (69.4%), ocular toxicity (68%), nail toxicities (61.1%), dermatologic toxicity (41.6%) hyperphosphataemia (55.6%), stomatitis (48.6%), and diarrhea (36.1%) were the most frequent, mainly G1-G2 AEs. Overall incidence of G3 AEs was 22.2%, while no patient experienced G4 AE. Dose reduction and temporary discontinuation were needed in 33.3% and 40.3% of cases, with 1 permanent discontinuation due to AEs.

CONCLUSIONS

These results confirm the effectiveness and safety of pemigatinib in a real-world setting.

Focus on RAS Codon 61 Mutations in Metastatic Colorectal Cancer: A Retrospective Analysis

RAS mutations involving codon 61 are rare in metastatic colorectal cancer (mCRC), accounting for only 1-4%, but they have recently been identified with high frequency in the circulating tumor DNA (ctDNA) of patients with secondary resistance to anti-EGFRs. This retrospective monocentric study aimed to investigate the clinical phenotype and prognostic performance of codon 61 RAS-mutated mCRC. Fifty patients with codon 61 RAS-mutated mCRC treated at our institution between January 2013 and December 2021 were enrolled. Additional datasets of codon 61 RAS wild-type mCRCs (648 patients) were used as comparators. The endpoint for prognostic assessment was overall survival (OS). Metastatic involvement of the peritoneum or ovary was significantly more frequent in codon 61 RAS-mutated mCRC compared to codon 61 RAS wild-type (54 vs. 28.5%), non-codon 61 RAS-mutated (35.6%), BRAF V600E-mutated (25%), and RAS/BRAF wild-type (20.5%) cohorts. At a median follow up of 96.2 months, the median OS for codon 61 RAS-mutated patients was significantly shorter compared to RAS/BRAF wild-type (26.9 vs. 36.0 months, HR 0.56) patients, while no significant difference was observed compared to non-codon 61 RAS-mutated and BRAF V600E-mutated patients. We showed a negative prognostic impact and a statistically significant correlation between codon 61 RAS mutations and metastatic involvement of the peritoneum and ovary.

An immune-related gene expression signature predicts benefit from adding atezolizumab to FOLFOXIRI plus bevacizumab in metastatic colorectal cancer

BACKGROUND

AtezoTRIBE phase II randomized study demonstrated that adding atezolizumab to first-line FOLFOXIRI (5fluoruracil, oxaliplatin, irinotecan) plus bevacizumab prolongs progression-free survival (PFS) of metastatic colorectal cancer (mCRC) patients, with a modest benefit among proficient mismatch repair (pMMR). DetermaIO is an immune-related 27-gene expression signature able to predict benefit from immune-checkpoint inhibition in triple-negative breast cancer. In this analysis of AtezoTRIBE, we investigated the predictive impact of DetermaIO in mCRC.

METHODS

mCRC patients unselected for MMR status were randomized(1:2) to FOLFOXIRI plus bevacizumab (control arm) or the same regimen with atezolizumab (atezolizumab arm). RT-qPCR by DetermaIO was performed on RNA purified from pre-treatment tumours of 132(61%) out of 218 enrolled patients. A binary result (IOpos versus IOneg) adopting the pre-established DetermaIO cut-point (0.09) was obtained, and an exploratory optimized cut-point (IOOPT) was computed in the overall population and in pMMR subgroup (IOOPTpos versus IOOPTneg).

RESULTS

DetermaIO was successfully determined in 122 (92%) cases, and 23 (27%) tumours were IOpos. IOpos tumours achieved higher PFS benefit from atezolizumab arm than IOneg (HR:0.39 versus 0.83, P interaction=0.066). In pMMR tumours (N=110), a similar trend was observed (HR:0.47 versus 0.93, P interaction=0.139). In the overall population, with the computed IOOPT cut-point (0.277), 16 (13%) tumours were IOOPTpos and they derived higher PFS benefit from atezolizumab than IOOPTneg(HR:0.10 versus 0.85, P interaction=0.004). Similar results were found in the pMMR subgroup.

CONCLUSIONS

DetermaIO may be useful to predict benefit of adding atezolizumab to first-line FOLFOXIRI plus bevacizumab in mCRC. The exploratory IOOPT cut-point should be validated in independent mCRC cohorts.

The role of the multidisciplinary tumor board (MDTB) in the assessment of pancreatic cancer diagnosis and resectability: A tertiary referral center experience

Background

The introduction of multidisciplinary tumor boards (MDTBs) for the diagnostic and therapeutic pathway of several oncological disease significantly ameliorated patients' outcomes. However, only few evidences are currently present on the potential impact of the MDTB on pancreatic cancer (PC) management. Aim of this study is to report how MDTB may influence PC diagnosis and treatment, with particular focus on PC resectability assessment and the correspondence between MDTB definition of resectability and intraoperative findings.

Methods

All patients with a proven or suspected diagnosis of PC discussed at the MDTB between 2018 and 2020 were included in the study. An evaluation of diagnosis, tumor response to oncological/radiation therapy and resectability before and after the MDTB was conducted. Moreover, a comparison between the MDTB resectability assessment and the intraoperative findings was performed.

Results

A total of 487 cases were included in the analysis: 228 (46.8%) for diagnosis evaluation, 75 (15.4%) for tumor response assessment after/during medical treatment, 184 (37.8%) for PC resectability assessment. As a whole, MDTB led to a change in treatment management in 89 cases (18.3%): 31/228 (13.6%) in the diagnosis group, 13/75 (17.3%) in the assessment of treatment response cohort and 45/184 (24.4%) in the PC resectability evaluation group. As a whole, 129 patients were given indication to surgery. Surgical resection was accomplished in 121 patients (93.7%), with a concordance rate of resectability between MDTB discussion and intraoperative findings of 91.5%. Concordance rate was 99% for resectable lesions and 64.3% for borderline PCs.

Conclusions

MDTB discussion consistently influences PC management, with significant variations in terms of diagnosis, tumor response assessment and resectability. In this last regard, MDTB discussion plays a key role, as demonstrated by the high concordance rate between MDTB resectability definition and intraoperative findings.

Efficacy of third-line anti-EGFR-based treatment versus regorafenib or trifluridine/tipiracil according to primary tumor site in RAS/BRAF wild-type metastatic colorectal cancer patients

Background

Right- (R) and left-sided (L) metastatic colorectal cancer (mCRC) exhibit different clinical and molecular features. Several retrospective analyses showed that survival benefit of anti-EGFR-based therapy is limited to RAS/BRAF wt L-sided mCRC patients. Few data are available about third-line anti-EGFR efficacy according to primary tumor site.

Methods

RAS/BRAF wt patients mCRC treated with third-line anti-EGFR-based therapy versus regorafenib or trifluridine/tipiracil (R/T) were retrospectively collected. The objective of the analysis was to compare treatment efficacy according to tumor site. The primary endpoint was progression-free survival (PFS); secondary endpoints were overall survival (OS), response rate (RR) and toxicity.

Results

A total of 76 RAS/BRAF wt mCRC patients, treated with third-line anti-EGFR-based therapy or R/T, were enrolled. Of those, 19 (25%) patients had a R-sided tumor (9 patients received anti-EGFR treatment and 10 patients R/T) and 57 (75%) patients had a L-sided tumor (30 patients received anti-EGFR treatment and 27 patients R/T). A significant PFS [7.2 vs 3.6 months, HR 0.43 (95% CI 0.2-0.76), p= 0.004] and OS benefit [14.9 vs 10.9 months, HR 0.52 (95% CI 0.28-0.98), p= 0.045] in favor of anti-EGFR therapy vs R/T was observed in the L-sided tumor group. No difference in PFS and OS was observed in the R-sided tumor group. A significant interaction according to primary tumor site and third-line regimen was observed for PFS (p= 0.05). RR was significantly higher in L-sided patients treated with anti-EGFR vs R/T (43% vs. 0%; p <0.0001), no difference was observed in R-sided patients. At the multivariate analysis, third-line regimen was independently associated with PFS in L-sided patients.

Conclusions

Our results demonstrated a different benefit from third-line anti-EGFR-based therapy according to primary tumor site, confirming the role of L-sided tumor in predicting benefit from third-line anti-EGFR vs R/T. At the same time, no difference was observed in R-sided tumor.

Role of Chemoradiation in the Adjuvant Treatment of Radically Resected Pancreatic Cancer Patients: A Mono-Institutional Retrospective Analysis

INTRODUCTION

Pancreatic cancer (PC) represents an unfavorable prognosis condition, even in patients with resectable disease. The aim of this series was to investigate the role of treatment intensification with adjuvant chemoradiation (CRT) in radically resected PC patients.

METHODS

Data from PC patients who underwent radical surgery, adjuvant chemotherapy (CT), and CRT throughout a 20-year period were retrospectively collected. Actuarial local control (LC) and the overall survival (OS) were the primary endpoints, with disease-free survival and metastasis-free survival (MFS) representing secondary endpoints.

RESULTS

The analysis included 108 PC patients treated with adjuvant CRT and CT from January 2000 to August 2019. Median age was 66 years (range: 40-83), and all patients underwent radical surgical resection with adjuvant CT (88, 81.5%) plus concomitant CRT (101, 93.5%) or radiotherapy alone (7, 6.5%). The median dose delivered to the tumor bed was 50.4 Gy (range: 45-50.6 Gy), while median dose to regional lymphatic drainage stations was 39.6 Gy (range 39.6-45 Gy). Concomitant CT was a gemcitabine-based regimen in the vast majority of patients (87, 80.6%). Median follow-up time was 21 months; the 2- and 5-year LC rates were 75.8% and 59.1%, respectively. Perineural invasion at pathological assessment was found significantly associated with LC (p = 0.028). Median OS was 40 months with 2- and 5-year OS rates of 73.9% and 41.6%, respectively.

CONCLUSIONS

The outcomes of this series suggest to investigate the possible impact of adding adjuvant CRT to CT in PC patients. Timing and combination of modern CRT with new systemic therapies need to be further investigated to personalize therapy and optimize clinical advantages.

Primary versus secondary antiemetic prophylaxis with NK1 receptor antagonists in patients affected by gastrointestinal malignancies and treated with a doublet or triplet combination regimen including oxaliplatin and/or irinotecan plus fluoropyrimidines: A propensity score matched analysis

Aim

The aim of the current study is to investigate the impact of primary compared to secondary chemotherapy-induced nausea and vomiting (CINV) prophylaxis with NK1 receptor antagonists (NK1-RA) in patients affected by gastrointestinal malignancies and treated with oxaliplatin- and/or irinotecan-based doublet or triplet regimens.

Study design and methods

Clinical data of patients affected by gastrointestinal malignancies, treated with an oxaliplatin and/or irinotecan-based doublet or triplet regimen as neo/adjuvant or advanced-line treatment, and who received NK1-RA as primary (from the first cycle of treatment) or secondary (after the onset of CINV with a previous regimen with 5HT3-RA and dexamethasone) prophylaxis for CINV, were retrospectively collected in an observational study involving 16 Italian centers. A propensity score matching was performed by taking into account the following stratification factors: sex (male vs. female), age (< vs. ≥70 years old), overweight (body mass index, BMI < vs. ≥25), underweight (BMI < vs. ≥19), disease spread (early vs. advanced/metastatic), tumor type (esophagogastric cancer vs. the rest, hepatobiliary tumor vs. the rest, colorectal cancer vs. the rest), type of NK1-RA used as primary/secondary prophylaxis (netupitant-palonosetron vs. fosaprepitant/aprepitant), concomitant use of opioids (yes vs. no), concomitant use of antidepressant/antipsychotic drugs (yes vs. no), Eastern Cooperative Oncology Group (ECOG) performance status at the start of NK1-RA treatment (0 vs. 1–2), and intensity of chemotherapy regimen (doublet vs. triplet).

Results

Among 409 patients included from January 2015 to January 2022 and eligible for analysis, 284 (69%) and 125 (31%) were treated with NK1-RA as primary and secondary antiemetic prophylaxis, respectively. After matching, primary NK1-RA use was not associated with higher rates of protection from emesis regardless the emesis phase (acute phase, p = 0.34; delayed phase, p = 0.14; overall phase, p = 0.80). On the other hand, a lower rate of relevant nausea (p = 0.02) and need for rescue antiemetic therapy (p = 0.000007) in the overall phase was found in primary NK1-RA users. Furthermore, a higher rate of both complete antiemetic response (p = 0.00001) and complete antiemetic protection (p = 0.00007) in the overall phase was more frequently observed in primary NK1-RA users. Finally, chemotherapy delays (p = 0.000009) and chemotherapy dose reductions (p = 0.0000006) were less frequently observed in primary NK1-RA users.

Conclusion

In patients affected by gastrointestinal malignancies, a primary CINV prophylaxis with NK1-RA, 5HT3-RA, and dexamethasone might be appropriate, particularly in those situations at higher risk of emesis and in which it is important to avoid dose delays and/or dose reductions, keeping a proper dose intensity of chemotherapy drugs.

Encorafenib plus cetuximab with or without binimetinib in patients with BRAF V600E-mutated metastatic colorectal cancer: real-life data from an Italian multicenter experience

Background

Encorafenib plus cetuximab with or without binimetinib showed increased objective response rate (ORR), progression-free survival (PFS), and overall survival (OS) compared with chemotherapy plus anti-EGFR in previously treated patients with BRAF V600E-mutated (mut) metastatic colorectal cancer (mCRC). Although no formal comparison was planned, addition of binimetinib to encorafenib plus cetuximab did not provide significant efficacy advantage.

Patients and methods

This real-life study was aimed at evaluating safety, activity, and efficacy of encorafenib plus cetuximab with or without binimetinib in patients with BRAF V600E-mut mCRC treated at 21 Italian centers within a nominal use program launched in May 2019.

Results

Out of 133 patients included, 97 (73%) received encorafenib plus cetuximab (targeted doublet) and 36 (27%) the same therapy plus binimetinib (targeted triplet). Most patients had Eastern Cooperative Group Performance Status (ECOG-PS) of 0 or 1 (86%), right-sided primary tumor (69%), and synchronous disease (66%). Twenty (15%) tumors were DNA mismatch repair deficiency (dMMR)/microsatellite instability (MSI)-high. As many as 44 (34%) patients had received two or more prior lines of therapy, 122 (92%) were previously exposed to oxaliplatin, and 109 (82%) to anti-vascular endothelial growth factor (anti-VEGF). Most frequent adverse events were asthenia (62%) and anti-EGFR-related skin rash (52%). Any grade nausea (P = 0.03), vomiting (P = 0.04), and diarrhea (P = 0.07) were more frequent with the triplet therapy, while melanocytic nevi were less common (P = 0.06). Overall, ORR and disease control rate (DCR) were 23% and 69%, respectively, with numerically higher rates in the triplet group (ORR 31% versus 17%, P = 0.12; DCR 78% versus 65%, P = 0.23). Median PFS and OS were 4.5 and 7.2 months, respectively. Worse ECOG-PS, peritoneal metastases, and more than one prior treatment were independent poor prognostic factors for PFS and OS. Clonality of BRAF mutation measured as adjusted mutant allele fraction in tumor tissue was not associated with clinical outcome.

Conclusions

Our real-life data are consistent with those from the BEACON trial in terms of safety, activity, and efficacy. Patients in good general condition and not heavily pretreated are those more likely to derive benefit from the targeted treatment.

•

Encorafenib plus cetuximab ± binimetinib is safe and effective for BRAF V600E mut mCRC even in the real-world setting.

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Median OS is slightly shorter than in the BEACON trial, probably due to less selected patients in real life.

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Patients deriving more benefit from targeted therapy are likely those in good general conditions and not heavily pretreated.

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BRAF adjusted MAF is worth further investigation to better characterize the genomic heterogeneity of BRAF V600E mut mCRC.

The impact of the histological classification of ampullary carcinomas on long-term outcomes after pancreaticoduodenectomy: a single tertiary referral center evaluation

PURPOSE

Ampullary carcinomas (ACs) are classified as pancreatobiliary (Pb-AC), intestinal (Int-AC), or mixed (Mixed-AC). The influencing role of AC subtypes on long-term outcomes is still matter of debate. Aim of this study is to evaluate the prognostic role of the three histological variants on the overall (OS) and disease-free survival (DFS) after pancreaticoduodenectomy(PD).

METHODS

All PDs for AC between 2004 and 2020 were included. Patients were classified according to the histological feature in Pb-AC, Int-AC, and Mixed-AC. Five-year OS and DFS were compared among the subtypes. Additionally, the prognostic role of the histological classification on OS and DFS was evaluated.

RESULTS

Fifty-six (48.7%) Pb-ACs, 53 (46.1%) Int-ACs, and 6 (5.2%) Mixed-ACs were evaluated. A poorer 5-year OS was evidenced for the Pb-AC group (54.1%) as compared to the Int-AC cohort (80.7%) (p = 0.03), but similar to the Mixed-AC population (33%) (p = 0.45). Pb-AC presented a worse 5-year DFS (42.3%) in comparison to the Int-AC (74.8%) (p = 0.002), while no difference was evidenced in comparison to the Mixed-AC (16.7%) (p = 0.51). At the multivariate analysis, the Pb-/Mixed-AC histotype was recognized as negative prognostic factor for both OS (OR: 2.29, CI: 1.05-4.98; p = 0.04) and DFS (OR: 2.17, CI: 1-4.33; p = 0.02).

CONCLUSION

Histological subtypes of AC play a relevant role in long-term outcomes after PD. Pb-ACs and Mixed-ACs show a more aggressive tumor biology and a consequent worse survival as compared to the Int-AC subtype.

Adjuvant therapy (AT) in patients (pts) with radically resected ampullary adenocarcinoma (AA): A monocentric retrospective analysis

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Background: Ampullary adenocarcinoma (AA) is a rare tumor. Radical surgery is the only curative treatment for localized AA. The role of AT is not clearly defined and previous evidence in literature is poor and controversial. Hence, we retrospectively analyzed radically resected AA pts at our Institution, investigating the impact of AT on survival and the role of possible prognostic and/or predictive factors. Methods: Radically resected AA pts were retrospectively included in the analysis, divided into two groups: pts receiving AT and pts undergoing only postoperative observation (PO). The following variables were collected: gender; age (≤ 65 vs > 65 years); baseline ECOG PS (0 vs ³ 1); histologic subtype (pancreatobiliary vs intestinal); tumor stage (T1-2 vs T3-4); nodal status (N0 vs N+), margin status (R0 vs R+); radiotherapy (yes vs no), AT regimen [Gemcitabine (GMZ)-based vs fluoropyrimidine (FP)-based treatment)]. The objective of the analysis was to evaluate the impact of AT on overall survival (OS). Univariate and multivariate analyses were performed. Results: From 2007 to 2021, a total of 69 pts with radically resected AA were identified: 41 (59%) pts received AT, 28 (41%) PO. The median age was 65 years (41-81), 42 (61%) were males, ECOG PS was ³ 1 in 45 (65%) pts. Tumor characteristics were: 31 (45%) pancreatobiliary, 26 (38%) intestinal, 9 (13%) mixed subtype and 3 (4%) not available; 41 (59%) pts had T3-T4 stage tumor; 34 (49%) were N+. Out of 41 pts receiving AT, 27 (66%) pts were treated with FP-based AT, 14 (34%) with GMZ-based AT; 16 (23%) pts received also RT. In the overall population, median OS was 59.8 months. At the univariate analysis, there was a statistically significant association of T status with OS (p 0.03), confirmed at multivariate analysis (p 0.03). Further variables (ECOG PS, AT, nodal status and histologic subtype) were not associated with survival. Among the 41 pts receiving AT, median OS was 58.7 months. At the univariate analysis, AT regimen was significantly associated with OS (p 0.02), and it was confirmed at the multivariate analysis. In particular, median OS was 59.8 and 28.3 months in pts receiving FP- and GMZ-based AT, respectively [HR 0.26, (95% CI: 0.09-0.78), p = 0.001]. Conclusions: Among pts with radically resected AA, AT, compared with PO, was not associated with a significant survival benefit. However, among pts receiving AT, FP-based regimen seems to significantly improve OS in comparison to GMZ-based regimen, independently of histologic subtype. Our findings, from a retrospective and limited case series, add to controversial literature data and miss to clarify the real impact of AT in radically resected AA pts. A randomized trial of AT vs PO would provide further information in this setting.

DNA damage repair (DDR) germline mutations (GMs) in pancreatic ductal adenocarcinoma (PDAC): A mono-institutional retrospective study

10587

Background: GMs in DDR genes, in particular BRCA1/2, are associated with increased risk of cancer, including PDAC. Their identification is crucial for the clinical relevance, the best treatment choice, and the family implications in cancer prevention. However, there are few data regarding the epidemiology and the prognostic role of DDR GMs in PDAC patients (pts). The aim of our study is to determine the prevalence of DDR GMs, their correlation with clinicopathological features and their prognostic role. Methods: Unselected PDCA pts, assessed by BRCA1/2 GM analysis or multigenic panel at our Institution, were retrospectively analyzed. We divided the overall population into three groups based on GMs: pts with pathogenic variants (PVs), pts with variants of uncertain significance (VUS) and pts with no alterations. Clinicopathologic characteristics and treatment data were collected. The incidence of DDR GMs variants and their association with overall survival (OS) were evaluated. Univariate and multivariate analyses for OS were performed. Results: From September 2019 to August 2021, 200 PDAC pts were tested for DDR GMs: all pts were evaluated for BRCA 1/2; 140 pts were tested for further DDR GMs by a multigenic panel. Twenty-five pts (12.5%) had PVs, 45 (22.5%) pts had VUS and 130 (65%) pts had no GMs. BRCA 1-2 PVs were found in 10 pts (5%). Out of 91 pts with metastatic disease, the rate of PVs BRCA1/2 was 8.8%. Among 140 pts tested with multigenic panel, further PVs included: 7 (5%) ATM, 5 (3.6%) MUTYH, 1 (0.7%) TP53, 1 (0.7%) BARD1, and 1 (0.7%) MSH6. The most frequent VUS were: CHECK2 (5%), APC (3.6%), ATM (3.6%) and BRCA2 (3.6%). Regarding cancer family history, a statistically significant difference was reported between the 3 group (76% in PV pts, 82% in VUS pts and 60% in pts with no GMs; p 0.01). No difference was found concerning age (p 0.69), stage at diagnosis (p 0.31) and platinum-exposure (p 0.27). Out of 189 evaluable pts, median OS was 23 months. A significant difference in OS was observed in the 3 groups (30 months in PVs pts, 14 months in VUS pts and 24 months in pts with no GMs, p 0.0006). No factor, including the presence or the type of GMs, age, stage and family history, was significantly associated with OS at the multivariate analysis. Conclusions: In our study, we observed a high incidence of DDR GMs PV (12.5%), beyond BRCA 1/2, regardless of age, stage and family history. Despite retrospective nature of our analysis, small population, and single-institution evaluation, our findings confirm the importance of genetic testing for BRCA1/2 and, where available, of a multigenic test in all PDAC pts, due to the therapeutic implications and cancer risk prevention in patients relatives. The prognostic role of DDR GMs and the impact of VUS remain unclear.

The impact of the multidisciplinary team (MDT) in the management of colorectal cancer (CRC)

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Background: The management of CRC is complex, particularly in metastatic disease, where it is crucial the definition of disease burden, the assessment of radiological response and the identification of the right timing for potential radical surgery or loco-regional treatments. A correct CRC evaluation and the subsequent choice of the most appropriate treatment strategy, need, therefore, a MDT involving surgeons, oncologists, radiologists, radiation oncologists, endoscopists, gastroenterologists and pathologists. Based on such considerations, we investigated the impact of the MDT meeting in the management of CRC at our Institution. Methods: We retrospectively evaluated all the cases discussed at our MDT meeting between September 2019 and September 2021. We collected data, both pre- and post-MDT meeting, regarding radiology evaluation (disease control vs progression), surgical assessment (yes vs no) and radiotherapy evaluation (yes vs no). Primary endpoint was the overall rate of discrepancy in evaluation between pre- and post-MDT meeting. Results: Between September 2019 and September 2021, 696 cases were presented at our MDT meeting. The median age was 65 years (24-86), 391 (56%) patients were male and 553 (79%) patients had metastatic disease at diagnosis. After MDT meeting, a total of 214 decisions were modified, for an overall discrepancy rate of 31%. In particular, among 377 cases discussed for radiology evaluation, 110 decisions (29%) were modified after a central imaging review: 80 cases initially evaluated as progressed disease before MDT meeting were defined stable after MDT meeting, for a discrepancy rate of 73%. Regarding the 246 cases discussed for surgical assessment on primary tumor and/or metastatic sites, treatment strategy changed in 86 cases (35%). More specifically, 16 cases (19%), evaluated unresectable before MDT meeting, were then considered resectable after MDT meeting. Finally, among the 71 cases discussed for radiotherapy evaluation, treatment strategy changed in 18 cases (25%). Conclusions: Our analysis demonstrates a significant rate of discrepancy in radiology and/or surgical evaluation between pre- and post-MDT meeting. Our results show that a MDT allows a considerable modification in CRC management, maximizing the treatment strategy, in particular avoiding unnecessary changes in therapy and allowing surgery where possible.

The impact of second-line treatment after fist-line cisplatin plus gemcitabine in advanced biliary tract cancers: A mono-institutional retrospective study

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Background: The prognosis of advanced biliary tract cancers (ABTCs) is poor with a 5 year overall survival (OS) lower than 20%. The standard of care first-line chemotherapy is the combination of cisplatin plus gemcitabine. The efficacy of second-line treatment is supported by few evidence and only one randomized phase III clinical trial is reported. The ABC-06 trial showed a minimal improvement in overall survival with FOLFOX compared to active symptoms control (ASC). Herein, we provide a retrospective analysis of patients treated with second-line treatment at our Institution investigating the impact of treatment regimen and possible prognostic or predictive factors. Methods: ABTCs patients receiving second-line treatment following a first-line chemotherapy with cisplatin plus gemcitabine were included in the analysis. The following variables were collected: gender; age (< 65 years vs ≥ 65 years); baseline ECOG PS (0-1 vs ≥2); second-line regimen (FOLFIRI vs FOLFOX); comorbidities (yes vs no); number of comorbidities (0-1 vs ≥ 2); number of metastatic sites (1 vs ≥2). Univariate and multivariate analysis for progression free survival (PFS) and OS were performed. Results: Fifty-one patients affected with ABTCs receiving second-line treatment between January 2016 and May 2021 were included in the analysis. The median age was 70 years (38-82), 39% (20) were males, 70% (36) were aged ≥ 65 years, ECOG PS was 0-1 in 86% (44) of patients; 39% (20) had ≥2 comorbidities; 60% (31) had ≥ 2 metastatic sites. Second-line regimen included FOLFIRI (28; 55%), FOLFOX (15; 29%), capecitabine (2; 4%) and experimental drugs (6; 12%). The overall population median PFS and OS at second-line were 3.5 months (median follow-up 11.4 months) and 8.8 months (median follow-up 22.6 months), respectively. Two patients (4%) achieved a partial response and the disease control rate was 39%. At the univariate and multivariate analysis, no variable was associated with PFS. At the univariate analysis, second-line regimen FOLFIRI (p = 0.03) and single metastatic site (p = 0.06) were associated with improved OS; at the multivariate analysis only the second-line regimen was confirmed associated with OS (p = 0.02). In particular, out of 43 evaluable patients, the median OS according to treatment (FOLFIRI vs FOLFOX) was 11.3 months versus 5.4 months (p = 0.019, HR 0.46, 95% CI: 0.18-0.88). Conclusions: Despite the retrospective analysis and the limited sample size, we confirm the importance of second-line chemotherapy in ABTCs patients, when feasible. Our results show that the second-line FOLFIRI regimen after a platinum-containing fist-line, was independently associated with improved OS. Given that the ABC-06 trial compared FOLFOX to ASC, a randomized trial of FOLFOX vs FOLFIRI as second-line would provide further information in this setting.

Management of single pulmonary metastases from colorectal cancer: State of the art

Colorectal cancer (CRC) is one of the most common causes of death from cancer. Lung seeding occurs in approximately 10% of patients surgically treated for primary CRC with radical intent: the lung is the most common site of metastases after the liver. While surgical treatment of liver metastases is widely accepted to affect long-term outcomes, more controversial and not standardized is the therapy for CRC patients developing lung metastases. Experience suggests the potential curative role of pulmonary metastasectomy, especially in oligometastatic disease. However, the optimal strategy of care and the definition of prognostic factors after treatment still need to be defined. This review focused on the uncommon scenario of single pulmonary metastases from CRC. We explored pertinent literature and provide an overview of the epidemiology, clinical characteristics and imaging of single pulmonary metastases from CRC. Additionally, we identified the best available evidence for overall management. In particular, we analyzed the role and results of locoregional approaches (surgery, radiotherapy or ablative procedures) and their integration with systemic therapy.

Phase II study of preoperative (PREOP) chemoradiotherapy (CTRT) plus avelumab (AVE) in patients (PTS) with locally advanced rectal cancer (LARC): The AVANA study

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Background: Preop CTRT is considered the standard of care in the management of LARC. RT can induce antigen release from a low neoantigen-burden tumor (such as a mismatch repair proficient colorectal cancer) and activate dendritic cells leading to a CD8+ T lymphocyte-mediated anticancer immune response. In LARC patients, neoadjuvant CTRT increases PD-L1 expression in tumor cells, strongly suggesting a neoadjuvant combinatory strategy with RT and PD-1/PD-L1 pathway blockade. Based on such considerations, we have designed the AVANA study to investigate the role of Ave in combination with preop CTRT in LARC. Methods: This is an Italian multi-center, phase II study. Pts with resectable LARC, defined by the presence of at least one of the following features: cN+, cT4, high risk cT3, received standard preop CTRT (capecitabine 825 mg/sqm/bid 5 days/week+ 50.4 Gy in 28 fractions over 5.5 weeks) plus 6 cycles of Ave 10 mg/Kg every 2 weeks. Surgery with total mesorectal excision was performed at 8-10 weeks after the end of CTRT. The primary end-point was the pCR rate, defined as complete histological regression with no available tumor cells ypT0N0. Secondary end-points were R0 resection rate, tumor downstaging, local recurrence, sphincter preservation rate, progression-free survival, overall survival, safety profile, and the evaluation of exploratory predictive and/or prognostic biomarkers. Assuming as null hypothesis p0 a pCR rate of 15%, a significance level of 5% (one-side), and a power of 80%, a sample size of 101 pts was needed to detect an absolute increment of 10% in pCR rate (from 15% to 25%). The experimental regimen is considered for further studies if, in at least 22 pts, we observe a pCR. Results: From April 2019 to November 2020, a total of 101 resectable LARC pts were enrolled in 10 Italian Centers. The median age was 63 years (23-82), 62 (61.4%) pts were male, 93 (92%) had ECOG PS 0. At baseline, 94 (93%) and 16 (16%) pts had cN+ and cT4 LARC, respectively. All pts completed the induction phase. Out of 96 pts evaluable for pathological response, 22 (23%) pts achieved a pCR and 59 (61.5%) pts a major pathological response (a central review is ongoing). At this time, microsatellite status is available only in 39 pts, of which only one was instable. The rate of grade 3-4 non-immune and immune-related adverse events was 8% and 4%, respectively. Avelumab was early interrupted in 9 pts out 101, mainly due to toxicity. Conclusions: The combination of preop CTRT plus Ave showed a promising activity and a feasible safety profile. According to our statistical considerations, the experimental regimen will be considered for further studies. Updated results will be presented during the Congress. Sponsored by GONO and partially supported by Merck. EUDRACT 2017-003582-10. Clinical trial information: NCT03854799.

The role of site of metastatic resection (MR) in metastatic colorectal cancer (mCRC) patients (PTS): A mono-institutional cohort study

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Background: Approximately 50%-60% of CRC pts develop metastases, usually to liver and lung. When feasible, MR is the only potentially curative option in the multimodal management of mCRC pts. Few studies have compared survival outcomes based on different surgical sites with contrasting data. Hence, we retrospectively analyzed mCRC pts, underwent radical lung and/or liver resection at our Institution, investigating the impact of resection site on overall survival (OS). Methods: mCRC pts underwent radical liver (group 1), lung (group 2) or liver and lung (group 3) resection were included. The following variables were collected: age ( > vs ≤ 65 years); gender (male vs female); primary tumor site (right vs left); synchronous vs metachronous; RAS/BRAF status; number (N) of MR (1, 2 or ≥3); chemotherapy treatment (No treatment vs Post-operative vs Peri-operative/pre-operative treatment) and chemotherapy regimen (5FU monotherapy, Oxaliplatin-based, Irinotecan-based regimen, FOLFOXIRI, Bevacizumab, Anti-EGFR). The association of MR site and OS was evaluated. Univariate and multivariate analyses for OS were performed. Results: A total of 191 mCRC pts underwent radical MR were included in the analysis: 112 (59%) pts in group 1, 38 pts (20 %) in group 2, 41 pts (21 %) in group 3. 145 (76%) pts had a left-sided tumor and 46 (24%) a right-sided tumor. Out of 156 evaluable pts, 73 (47%) pts harbored a RAS mutation, while out of 136 evaluable pts, 4 (3%) pts had a BRAF mutation. Regarding the N of MR, 125 pts (65%) underwent 1 radical MR, 43 (23%) pts 2 MR and 23 (12%) ≥3 MR. In the overall population, median OS was 77.2 months. According to MR site, median OS was 59.4, not reached (NR) and 99.1 months, in group 1, 2 and 3, respectively (p = 0.075). At the multivariate analysis no significant association with OS was shown for MR site, while the N of MR and RAS status were indipendently associated with OS. Median OS was 58.5, 97.7 months and NR in pts underwent 1, 2 and ≥3 MR, respectively (p = 0.02). Median OS was 58.5 and 83.1 months in RAS mutated and RAS wild-type pts, respectively (p = 0.12). Conclusions: Despite the limited number of pts and the retrospective nature of our study, these results confirmed that surgery represents the only option with curative intent for mCRC pts, independently of metastatic site (liver vs lung vs liver and lung). Based on our analysis, a higher number of MR is associated to a better outcome, and this could be explained with an accurate selection of patients that could benefit from multiple radical resections. Thus, a multidisciplinary approach is essential for the management of mCRC pts and surgery should be evaluated case by case and always performed when possible, even several times, independently of site of MR.

The impact of first-line chemotherapy in elderly patients (pts) with advanced pancreatic cancer (APC): A mono-institutional retrospective study

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Background: Pancreatic cancer median age at diagnosis is 70 years old. However, elderly pts are underrepresented in randomized clinical trials (RCTs) and chemotherapy efficacy and safety data in this population are limited. Herein, we present a retrospective analysis of an elderly population treated at our Institution, investigating the role of baseline clinical factors in guiding treatment decision making. Methods: Pts aged ≥70 years old receiving a first-line chemotherapy for APC were included in the analysis. The primary end-points were progression-free survival (PFS) and overall survival (OS). The following variables were collected: gender; age (≥ 70 and < 75 years vs ≥ 75 years); baseline ECOG PS (0-1 vs 2-3); site of primary tumor (head/uncinate process vs body/tail); disease stage (locally advanced vs metastatic); baseline CA 19.9 ( < vs ≥ 200); chemotherapy regimen; comorbidities (yes vs no); number of comorbidities (0-1 vs ≥ 2). Univariate and multivariate analysis for PFS and OS were performed. Results: A total of 169 APC pts aged ≥70 years old, receiving first-line chemotherapy between March 2015 and August 2020, were included in the analysis. The median age was 76 years (70-89), ECOG PS was 0-1 in 77% of pts; 70% were metastatic; 70% of pts had a head/uncinate process primary tumor; 25% had baseline CA 19.9 ≥ 200; 9.4% of pts had no comorbidities and 50% had ≥2 comorbidities. The majority of pts received gemcitabine nab-paclitaxel (60%), other regimes included gemcitabine (28%), FOLFIRINOX (5%), capecitabine (4%), FOLFOX (2%) and FOLFIRI (1%). The overall population median PFS and OS were 6.5 (median follow-up 19.1 months) and 11 months (median follow-up 21.8 months), respectively. Out of 164 pts evaluable, 38 (23%) pts achieved a partial response and 58 (35%) a stable disease, with a disease control rate of 58%. At the multivariate analysis, ECOG PS 0-1 resulted independently associated both with improved PFS (p 0.005) and OS (p 0.0084). At the multivariate analysis for PFS, also locally advanced stage resulted significantly associated with better PFS (p = 0.036). In pts with ECOG PS 0-1 vs 3-4 the median PFS was 6.7 vs 3.3 months (p 0.0004) and median OS was 11.3 vs 5.5 moths (p 0.003), respectively. Conclusions: Despite the retrospective nature of the analysis and the limited sample size, we observed that elderly APC pts can benefit from a first-line treatment achieving survival outcomes comparable to the one reported for younger pts in RCTs. On the basis of our results, the baseline ECOG PS can be considered a prognostic factor for both PFS and OS. In conclusion, elderly pts should not be precluded from an active treatment and careful patient selection, mainly according to baseline ECOG PS, should guide treatment indication.

The role of primary tumor (PT) site as prognostic factor after resection of colorectal (CRC) liver metastases (LM): A mono-institutional cohort study

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Background: Radical resection of LM is the only chance of cure for liver-only mCRC pts. Besides the evaluation of technical resectability, several factors must be taken into account for the evaluation of recurrence risk. Among them we should consider the Fong Risk Score and its modified version, including RAS/BRAF status (Brudvik’s score). Tumor sidedness is an important prognostic factor in CRC. The impact of PT site on the outcome of LM resection is still debated. Hence, we retrospectively analysed mCRC pts, underwent to radical LM resection at our Institution, investigating the impact of PT site on DFS and OS. Methods: Liver-only mCRC pts underwent to radical LM resection were included. The association of PT site with DFS and OS was evaluated. The following variables were collected: gender; age (≥ vs < 75 years ); ECOG PS; CEA baseline level; PT site; RAS and BRAF status; mucinous histology; grading (G1-2 vs G3); RECIST response during preoperative treatment; resected PT; synchronous vs metachronous; number of LM; bilobar vs unilobar LM; LM diameter ≥ 5 cm; R0 vs R1 resection. Univariate and multivariate analyses for DFS and OS were performed. Results: A total of 463 liver-only mCRC pts underwent to radical LM resection were included. Seventy (15%) pts had a right-sided (r-s) tumor and 393 (85%) pts a left-sided (l-s) tumor. R-s CRC pts more often had RAS/BRAF mutations in comparison to l-s tumors (76% vs 37%; p < 0.0001). Median DFS and OS was 13.1 and 41.6 months, respectively, in r-s CRC vs 16.0 (p = 0.65) and 62.2 months (p = 0.033), respectively, in l-s tumors. At the multivariate analysis no significant association with survival parameters was shown for tumor sidedness. At the multivariate analysis, R0 resection was independently associated both with better DFS and OS; RAS/BRAF wt CRC and resected PT were significantly associated with improved OS. Considering all wt CRC pts (N = 237), 14 (6%) pts had r-s tumor and 223 (94%) l-s tumor. No significant association of tumor sidedness with survival was shown (DFS r = 10.0 vs l = 16.0 months, p = 0.62; OS r = 40.3 vs l = 66.2 months, p = 0.12). Conclusions: Our results showed that a significant smaller proportion of r-s CRC underwent to radical LM resection, indirectly confirming its worse prognosis. Among radically resected pts, r-s CRC was associated to a shorter OS (significant) and DFS (not significant) compared to l-s CRC, but it was not confirmed at the multivariate analysis. We can conclude that right PT site should not be considered as a contraindication for radical LM surgery, when feasible.

The impact of 2nd-line treatment (tx) after 1st-line Gemcitabine plus Nab-paclitaxel (GemNab) in advanced pancreatic cancer (APC) patients (pts)

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Background: Three main phase III randomized studies investigated the role of 2nd-line tx in APC pts. The PANCREOX study failed to demonstrate a survival advantage of mFOLFOX vs 5FU/LV. Conversely, the CONKO-003 and NAPOLI-1 trials, demonstrated a significant survival improvement from the combination regimen OFF and 5FU+Nal-IRI, respectively, in comparison to 5FU/LV alone. Recently, final OS analysis from NAPOLI-1 demonstrated an association of specific characteristics (ECOG PS, age, Ca 19.9 baseline level, neutrophil-to-lymphocyte ratio and no liver metastases (m)) with OS > 1 year. The main limit of all these studies was due to the period they were carried out: no pts received 1st-line GemNab. Hence, we retrospectively analysed an homogeneous population of APC treated with 1st-line GemNab at our Institution, investigating the impact of 2nd-line tx. Methods: APC pts receiving a 2nd-line tx after 1st-line GemNab were included in the analysis. The following variables were collected: gender; age ( > vs ≤ 55 years and ≥ vs < 70 years ); baseline ECOG PS (0-1 vs 2-3); Ca 19.9 baseline level (≥ vs < 200); anamnesis of diabetes; site of primary tumor (head/uncinate process vs body/tail); number of m sites (1 vs > 1); m sites (liver, peritoneum, lung, nodes); RECIST response and ETS during 1-line GemNab. Univariate and multivariate analyses for PFS and OS were performed. Results: Out of 167 APC pts progressed to 1st-line GemNab, 93 (56%) pts received a 2nd-line tx, specifically 58 pts received an oxa-based regimen, 11 FOLFIRINOX, 8 FOLFIRI and 16 pts received other tx. Median 2nd-line PFS and OS were 3.3 and 5.6 months, respectively. Out of 87 pts evaluable for response, 7 pts achieved a partial response and 27 a stable disease, with a RR and a disease control rate (DCR) of 8% and 39%, respectively. Pts with baseline ECOG PS 0-1 had a significant better outcome in comparison to pts with PS 3-4 (PFS 4.2 vs 1.2 months, p < 0.0001; OS 7.2 vs 2.6 months, p = 0.0001). This significant association with survival parameters and ECOG PS was confirmed at the multivariate analysis. Conclusions: Despite the limited number of pts evaluated and the restrospective nature of our analysis, our results are in line with previous evidences, confirming the importance of a 2nd-line combination tx, when feasible, as well in an homogeneous population of APC pts treated with 1st-line GemNab. On the basis of our results, ECOG PS may be considered a prognostic factor and the choice of 2nd-line tx should be guided in primis by the baseline general conditions of APC pts.

Efficacy of third-line anti-EGFR-based treatment (tx) versus (vs) Regorafenib/TAS-102 (R/T) according to primary tumor site in RAS/BRAF wild-type (wt) metastatic colorectal cancer (mCRC) patients (pts)

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Background: Right- (R) and left-sided (L) mCRCs exhibit different clinical and molecular features. Several retrospective analyses showed that the survival benefit of anti-EGFR-based tx is limited to RAS/BRAF wt L-sided mCRC pts, which a larger effect in the first-line setting. Few data are available concerning the anti-EGFR efficacy according to primary tumor site in third line. Methods: Pts affected by RAS/BRAF wt mCRC treated with third-line anti-EGFR-based tx or R/T were retrospectively collected. The objective of the analysis was to compare tx activity and efficacy according to tumor site. Primary endpoint was PFS; secondary endpoints were OS and RR. PFS and OS analyses were performed using Kaplan-Meier method, and survival curves were compared using the log-rank test. RR was evaluated according to RECIST criteria and it was compared in the two groups using Fisher’s exact test. Statistical significance was set at p = 0.05 for a bilateral test. Univariate and multivariate analyses for PFS and OS were performed. Results: A total of 76 RAS/BRAF wt mCRC pts, treated with third-line anti-EGFR-based tx or R/T, were enrolled. Of those, 19 (25%) pts had R-sided tumor (9 pts received anti-EGFR tx and 10 pts received R/T) and 57 (75%) pts had L-sided tumor (30 pts received anti-EGFR tx and 27 pts received R/T). As shown in the table, a significant PFS and OS benefit in favor of anti-EGFR tx vs R/T was observed in L-sided pts, while no difference both in PFS and OS was observed in R-sided pts. RR was significantly higher in L-sided pts treated with anti-EGFR vs R/T, no difference was shown in R-sided pts. At the multivariate analysis, tx regimen was indipendently associated with PFS in L-sided pts, but not in R-sided pts. Conclusions: Our study confirmed the results deriving from the retrospective analysis of the phase III study 20020408. Our results demonstrated a different benefit from third-line anti-EGFR tx according to primary tumor site, confirming the role of L-sided tumor in predicting benefit from third-line anti-EGFR vs R/T, while no difference was observed in R-sided tumors. [Table: see text]

The role of response as predictor of improved outcome in advanced pancreatic cancer (APC) patients (pts) treated with first-line Gemcitabine plus Nab-paclitaxel (GemNab)

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Background: GemNab is one of the first-line standard treatment (tx) of APC. To date, no predictive factors, both clinical and molecular, of benefit from this regimen exist. Two retrospective studies showed that early tumor shrinkage (ETS) can predict an improved outcome in APC pts receiving a first-line tx with FOLFIRINOX or GemNab. However, data regarding GemNab, limited to a small population of only 57 pts, seem to not confirm the association of ETS with a better outcome. Hence, we retrospectively analysed an homogeneous population of APC treated with first-line GemNab at our Institution, investigating the impact of several clinical factors, including response and ETS. Methods: APC pts receiving a first-line tx with GemNab were included in the analysis. The association of RECIST response and ETS with PFS and OS was evaluated. The following variables were collected: gender; age ( > vs ≤ 55 years and ≥ vs < 70 years ); baseline ECOG PS; Ca 19.9 baseline level (≥ vs < 200); anamnesis of diabetes; site of primary tumor (head/uncinate process vs body/tail); locally A vs metastatic (m) PC; synchronous vs metachronous; number of m sites (1 vs > 1); m sites (liver, peritoneum, lung, nodes); number of tx lines (1 vs > 1). Univariate and multivariate analyses for PFS and OS were performed. Results: A total of 184 APC pts receiving first-line GemNab at our Institution from February 2014 to May 2019 were included in the analysis. RR and ETS were assessed in 174 and 168 pts, respectively. RR was 30%, disease control rate (DCR) 63% and ETS was 24%. Responders had a significant better PFS (12.5 vs 5.7 months, p < 0.0001) and OS (25.1 vs 12.1 months, p < 0.0001). ETS was significantly associated with improved PFS (12.3 vs 6.2 months, p < 0.0001) and OS (24.0 vs 12.8 months, p < 0.0001). At the multivariate analysis a significant association with survival parameters was confirmed for RECIST response, but not for ETS. At the multivariate analysis, also metachronous disease and number of tx lines > 1 were independently associated with better OS. Conclusions: Despite its retrospective nature, this is one of the largest series of APC pts treated with first-line GemNab investigating the role of RECIST response and ETS in predicting outcome. On the basis of our results, RECIST response may be considered a positive prognostic factor, whereas ETS does not. In conclusion, achieving tumor shrinkage, not necessarily early, significantly delays PC progression and prolongs survival in pts treated with first-line GemNab.

The impact of a multidisciplinary approach (MA) in the management of pancreatic disease (PD)

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Background: The management of PD is very insidious, mainly due to the often difficult differential diagnosis between benign and malignant diseases, and, in case of pancreatic ductal adenocarcinoma (PDCA), to the frequently hard differentiation among resectable/borderline PDCA susceptible to upfront surgery, locally advanced PDCA susceptible to a neoadjuvant approach and never resectable or metastatic PDCA in which a palliative treatment is the only option. A correct PD evaluation and the subsequent choice of the most appropriate treatment strategy, thus, need a MA, involving surgeons, oncologists, radiologists, radiation oncologists, endoscopists, gastroenterologists and pathologists. On the basis of such considerations, we investigate the impact of the multidisciplinary meeting (MM) in the management of PD at our Institution. Methods: We retrospectively evaluated all the cases discussed by surgeons at our MM. We collected data, both pre- and post-MM, regarding diagnosis (cyst vs pancreatitis vs IPMN vs PDCA), and, in case of PDCA, tumor burden at baseline (resectable vs border-line resectable vs locally advanced vs metastatic disease) and disease response to treatment (disease control vs progression). Primary endpoint was the overall rate of discrepancy in diagnosis and/or PD evaluation between pre- and post-MM. Results: From October 2018 to December 2019, a total of 139 cases were presented by surgeons. After MM, a total of 38 diagnosis and/or PD evaluation were modified, for an overall discrepancy rate of 27%. In particular, of the 38 discordant cases, 9 (24%) were initial diagnosis, 24 (63%) baseline tumor burden assessments and 5 (13%) were PDCA response evaluations. Among the 24 cases of tumor burden evaluations, treatment strategy changed in 17 out of 24 cases. More specifically, of the 19 cases, evaluated as borderline/resectable before the MM, 15 were defined as locally-advanced or metastatic disease after the MM; of the 5 cases, evaluated as not resectable before the MM, 2 were considered border-line/resectable after the MM. Similarly, out of 9 cases of discrepant initial diagnosis, 5 cases, considered as malignant disease before MM, were assessed as benign after the MM. Conclusions: Our analysis demonstrates a significant rate of discrepancy in diagnosis and/or PD evaluation between pre- and post-MM. Our results show that a MA allows a considerable modification in PD diagnosis and evaluation, maximizing the treatment strategy, in particular avoiding unnecessary and detrimental pancreatic surgery.

Retreatment With Anti-EGFR Antibodies in Metastatic Colorectal Cancer Patients: A Multi-institutional Analysis

BACKGROUND

On the basis of retrospective analyses and phase 2 studies, metastatic colorectal cancer patients whose disease responded to a first-line regimen containing an anti-epidermal growth factor receptor (EGFR) agent may experience benefit from anti-EGFR readministration in later therapy lines. While the analysis of circulating tumor DNA seems a promising tool to select the best candidates for this strategy, identifying clinical predictors of anti-EGFR sensitivity would be useful to drive treatment choices in daily practice.

PATIENTS AND METHODS

A real-life database of 5530 patients treated at 6 institutions was queried. Included were patients who were retreated with anti-EGFRs, who had RAS/BRAF wild-type-status tissue samples, who had received a first-line anti-EGFR-based regimen with at least stable disease as best response, and who had received at least one further line of therapy before anti-EGFR retreatment. The association with overall response rate (ORR), progression-free survival (PFS), and overall survival (OS) of variables potentially related to anti-EGFR sensitivity was investigated.

RESULTS

A total of 86 patients were identified. The ORR during anti-EGFR retreatment was 19.8%; median PFS and OS were 3.8 and 10.2 months, respectively. No significant association of clinical features of anti-EGFR sensitivity with ORR, PFS, and OS was observed. Among the 56 patients with a time from the last anti-EGFR administration to first-line progressive disease of < 3 months (rechallenge group), > 2 prior therapy lines and a longer anti-EGFR-free interval were associated with higher ORR, but not with longer PFS or OS.

CONCLUSION

Clinical features we deemed surrogates of anti-EGFR sensitivity were not reliable predictors of benefit from anti-EGFR retreatment.

Chemotherapy rechallenge or reintroduction (CTr/r), regofenib (REG) and TAS-102 for metastatic pretreated colorectal cancer (mCRC) patients (pts): A propensity score analysis of treatment beyond second-line (PROSERpINA Study)

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Background: The optimal treatment for mCRC beyond 2nd line is still questioned. Recently, REG and TAS-102 showed to improve survival compared to BSC. While in real-world practice CTr/r is often considered in this setting, supporting evidences are limited. In absence of studies comparing all these strategies, we aimed to compare the prognostic performance of CTr/r, REG and TAS-102 in mCRC treated beyond 2nd line. Methods: mCRC pts progressing after at least 2 lines of CT, treated with CTr/r, REG or TAS-102 between Jan-10 and Jan-19 were considered eligible. The primary endpoint was OS; secondary endpoints were PFS and RR. Cox’s proportional hazard models for survivals were estimated. A propensity score (PS) adjustment for baseline characteristics was further accomplished for survival analysis. Results: The clinical data of 341 pts (CTr/r 133, REG 150, TAS-102 58) were retrospectively collected. At multivariate analysis type of treatment, ECOG PS, number of metastatic sites and treatment line independently correlated with OS ( p < .001, p .001, p < .001 and p .029, respectively). The mOS was 18.5 (95% CI, 14.3–22.7), 6 (95% CI, 5.6–9.5) and 7.6 months (95%CI, 5.6–9.5), for CTr/r, REG and TAS-102 group, respectively (log-rank p < .0001). mOS was significantly longer for pts receiving CTr/r than for those treated with REG/TAS-102 (15.8 vs 7.1 months; adjusted HR 1.96, 95% CI 1.44-2.66; p < .0001) at the PS analysis, adjusted for ECOG PS, number of metastatic sites and treatment line; 2-yrs OS was 34% and 11.6% for CTr/r and REG/TAS-102, respectively. PFS was significantly longer for pts receiving CTr/r than for those treated with REG/TAS-102 (5.5 vs 3.9 months; HR 1.45, 95% CI 1.11-1.91; p .006) at the PS analysis. Accordingly, RR was higher in pts receiving CTr/r compared to REG/TAS-102 (29.0 vs 1.5%; Chi-square p < .00001). Conclusions: Our analysis, although underpowered, generates the hypothesis of a superiority of CTr/r in comparison to REG or TAS-102, in both efficacy and activity. Given the retrospective nature of our analysis, and the potential role of selection bias in treatment assignment, a prospective validation is mandatory.

Efficacy of retreatment with anti-EGFRs in mCRC is not predictable by clinical factors related to prior lines of therapy: A multi-institutional analysis

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Background: Retrospective analyses and phase 2 studies suggest that administering an anti-EGFR in advanced lines may be effective in mCRC pts who achieved benefit from a 1st-line anti-EGFR containing regimen. The identification of clinical features associated with benefit from anti-EGFR re-treatment (re-tx) in pts experiencing PD during 1st-line anti-EGFR (rechallenge) or after its interruption (reintroduction), is a major clinical need. Methods: A real-life data-base including a total of 5530 pts treated at 6 insitutions from December 2010 to October 2018 was queried. Pts retreated with anti-EGFRs, with RAS/ BRAF wild-type status on tissue samples, who had received a 1st-line anti-EGFR-based tx with at least SD as best response, and at least one further line of therapy before anti-EGFR re-tx, were included. The association with RECIST response (RR), PFS and OS was investigated for the following variables: RR (PR or CR vs SD) and PFS during 1st-line; time from the last anti-EGFR administration to 1st-line PD (i.e. re-introduction vs rechallenge); reason for anti-EGFR discontinuation in 1st-line (PD vs. other); number of anti-EGFR-free lines of therapy before re-tx; anti-EGFR free interval (time between the last anti-EGFR administration in 1st-line and the time of re-tx); primary tumor side; time from the diagnosis of metastatic disease to re-tx (≥ vs. < 18 mos). Results: Data from 86 patients were retrieved, 56 (65%) and 30 (35%) received anti-EGFR rechallenge or reintroduction, respectively. Median anti-EGFR free interval was 15.1 mos. The RR during re-tx was 19.8%, with a DCR of 46.5%. Median PFS and OS were 3.6 and 10.2 mos, respectively. No significant association of investigated features with RR and PFS was observed. No differences in RR or PFS were observed among patients receiving anti-EGFR re-tx as rechallenge or reintroduction (20.4% vs 23.1%, p = 0.99; median PFS: 3.49 vs 4.97 mos, p = 0.61). Patients with left-sided tumors had longer OS (HR: 0.50, 95%CI: 0.26-0.93, p = 0.005). Conclusions: Clinical factors that are generally believed to affect the efficacy of anti-EGFR re-tx are not confirmed in our series. Therefore, clinicians should not rely on those characteristics in their decision-making on anti-EGFR re-tx, and adequate studies for implementing liquid biopsy in clinical practice are urgently needed.

Colorectal cancer lung metastasis: Could multidisciplinary management suggest the right strategy?

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Background: Unlike liver metastases surgery, the resection of colorectal cancer lung metastasis (CCLM) is not standardized and data are still poor. Therefore, we conducted a retrospective analysis to evaluate the management of CCLM at our Centre. Methods: We retrospectively analyzed patients (pts) with CCLM treated at our Institution from Jan-2007 to Jan-2017. Aim of the study was to evaluate the impact of clinical and pathological features with survival outcomes (DFS and OS). Differences were compared with the use of log-rank test and parameters considered statistically significant ( p value < 0.5) at univariate were compared at multivariate analysis. Results: 141 pts were included in the analysis. 87 pts received a preoperative chemotherapy (pCT) and 54 an adjuvant (a)CT. In the whole population median DFS (mDFS) was 24 m (20-24) and median OS (mOS) 54 m (46-82), while 21 m (20-34) and 65 m (45-108) for pts undergoing pCT and 15 m (20-28) and 53 m (38 – 76) for those receiving aCT respectively, without statistically significant differences (p=0.4). Age, gender, PS, disease-free interval (DFI) (> or <24 months), primary tumor sidedness, mucinous histology, grading, RAS status, timing of lung metastasis (metachronous vs synchronous), number of lesions (>2), metastasis location (uni vs bilateral) and liver resection were evaluated at univariate and multivariate analysis. DFS was correlated with DFI > 24m (p=0.02), timing (p=0.03), number (p<0,0001) of metastasis and metastasis location (p=0.01) whereas OS was associated to DFI (p=0.02), number (p=0.0005), metastasis location (p=0.037) and RAS status (p=0.05) at univariate. At multivariate analysis, number of lesions correlated to DFS (p=0.0006) while DFI (p=0.0034) and RAS status (p=0.05) to OS. Conclusions: Our single Centre retrospective experience suggests an important clinical impact from surgery of CCLM based on mOS of the whole population. These data strengthen the role of a multidisciplinary management to allow pts to achieve surgery whenever possible, regardless of previous liver surgery, metachronous vs synchronous metastasis, DFI and RAS status.

Efficacy of anti-EGFR-based treatment (tx) in second-line and beyond according to tumor location (TL) in RAS/BRAF wild-type (wt) metastatic colorectal cancer (mCRC) patients (pts): A mono-institutional retrospective analysis

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Background: Right- (R) and left-sided (L) mCRCs exhibit different clinical and molecular features. Several retrospective analyses showed that the survival benefit of anti-EGFR-based tx is limited to RAS/BRAF wt L-sided mCRC pts, with a larger effect in the first-line setting. Few data are available concerning the anti-EGFR efficacy according to TL in 2nd and following lines. Methods: Pts affected by RAS/BRAF wt mCRC treated at our Institution with anti-EGFR-based tx in 2nd and following lines were retrospectively collected. The objective of the analysis was to compare tx activity and efficacy according to TL. Primary endpoint was overall survival (OS); secondary endpoints were progression free survival (PFS) and response rate (RR). Results: A total of 47 RAS/BRAF wt mCRC pts treated with an anti-EGFR-based tx in 2nd and following lines were identified. Of those, 32 (68%) were L-sided and 15 (32%) R-sided, respectively. Pts (age, gender, PS ECOG) and tumor (number of metastatic sites) characteristics and number of tx lines were well balanced between the two 21 pts received anti-EGFR alone, 26 pts anti-EGFR plus CT. mOS was 22.3 in L-sided and 7.3 months in R-sided group (HR 2.3, 95%CI 1.02-5.14, p = 0.04). At multivariate analysis TL and PS ECOG independently correlated with OS ( p = 0.02 and p =0.0089). mPFS was 8.4 and 3.9 months in pts with L-sided and R-sided tumor, respectively (HR 1.3; 95%CI 0.64-2.80, p =0.43). RR was higher in L-sided compared to R-sided tumor (37.5 vs 13.3) ( p= 0.09). Conclusions: Our analysis, although limited by the small sample and by its retrospective nature, indicates a better OS in L-sided compared to R-sided tumors treated with anti-EGFR-based tx in 2nd and following lines. A prospective validation is warranted.

Clinical, pathological and prognostic features of rare BRAF mutations (MTs) in metastatic colorectal cancer (mCRC): A bi-institutional retrospective analysis (REBUS study)

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Background: Recently, 3 classes of BRAF MTs have been described. BRAF V600 MTs, which identify mCRC with poor prognosis and not benefitting from anti-EGFR drugs, belong to class 1. Class 2 and 3 include BRAF non-V600 MTs, which occur in about 1-2% mCRC and are associated to favourable prognosis and specific clinicopathologic features. Class 2 and 3 differ in kinase activity and sensitivity to anti-EGFR: class 2 are activated and RAS-independent MTs; class 3 are kinase-dead and sensitive to inhibition of This study aims to retrospectively evaluate features and prognostic role of rare BRAF non-V600 compared to BRAF V600E MTs in mCRC pts treated at 2 Italian Institutions. Methods: mCRC pts harboring BRAF MTs, assessed by means of NGS, pyrosequencing or RT-PCR, treated between Jan-13 and Dec-18 at 2 Italian Institutions, were retrospectively analyzed. Clinico-pathological and treatment characteristics and survival data were collected. Results: 55 pts bearing BRAF MTs were identified. Of those, 46 (84%) harbored a V600E and 9 (16%) a non-V600 MT. Within the non-V600 group, 3 MTs (K601E, G469A, G469R) belonged to class 2, while 5 MTs (G466E, G466A, 2 D594G, D594N), belonged to class 3. One pt harboured a T599I MT, whose kinase activity is unknown. Compared to BRAF V600E mCRC, BRAF non-V600 mCRC were more frequently left-sided ( p .017) and displayed a lower grade ( p .045). In addition, non-V600 mCRC pts had a lower tumor burden (involving one metastatic site) ( p .026) and underwent more frequently to resection of metastases with radical intent (77.7 vs 18%; p .000175). mOS was significantly longer in the non-V600 compared to the V600E group (61.3 vs 20.4 m; HR 0.41, 95%CI 0.18-0.93; p .05). No difference in activity and efficacy of anti-EGFR agents was observed between class 2 and 3. Conclusions: Despite the small size of our retrospective analysis, the results were consistent with previous evidences. BRAF non-V600 MTs identified a subgroup of mCRC, differing both in terms of clinicopathologic characteristics and prognosis from BRAF V600 mCRC. Interestingly, the better prognostic features allowed more frequently radical resection of metastases, positively impacting on survival.

K-RAS codon 13 mutation in advanced colorectal cancer: A single-center retrospective study investigating prognostic outcomes and treatment strategies

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Background: Ras genes are markers of resistance to anti-EGFR therapies. Emerging evidences suggest that each mutation, independently from its predictive role of response/resistance to specific treatments, may be expression of different diseases with different biologic behaviours. We collected data of mCRC patients harbouring K-Ras codon 13 mutation to evaluate response to therapy, PFS and OS. Methods: We retrospectively collected data of advanced colorectal cancer patients harbouring K-Ras codon 13 mutation treated at our Institution between 2004 and 2014. Results: A total of n.33 K-Ras codon 13 mutated patients were analysed. N.24 patients (72,7%) had synchronous metastatic disease. None of the patients received anti-EGFR treatment, while n.25 patients received anti-VEGF agent bevacizumab in association to chemotherapy with fluoropirimidines plus oxaliplatin and/or irinotecan (n.21 as frontline therapy, n.4 in second line). ORR was 51,5% (17/33) on first-line therapy, 22,2% (6/27) on second-line therapy and 16,6% (2/12) on third-line therapy. Median PFS was 14,1 months after first-line therapy, 9,3 months after second-line therapy, 6,4 months after third-line therapy. Median OS was 35,5 months (events: 19/33). N.14 patients received metastases surgery with radical intent. OS in this population has not been reached yet at a median follow-up of 38 months, even though all patients had a relapse. OS among patients undergone to systemic only strategy was 31 months. Conclusions: At our knowledge, this is the first report suggesting a favourable prognosis for K-ras codon 13 mutated patients, with a median overall survival even superior to pan-RAS wild-type patients. Indeed, the high percentage of advanced patients at diagnosis (72.7%), the high responsiveness to chemotherapy even in third line, the high percentage of patients converted to surgery (42.4%) in an unselected population, together with the high risk or relapse after surgery, suggest K-ras codon 13 mutated disease is probably a biologically aggressive disease. Nevertheless our data prompt that these patients may benefit aggressive strategies of treatment and multidisciplinary evaluation.

[Early signs and symptoms before the psychotic onset. A study on the Duration of Untreated Illness (DUI) in a sample of patients with diagnosis of "non-affective psychotic disorders"]

AIMS

The aims of the study are to evaluate, in the Italian context, the presence and clinical features of early prodromal symptoms before the psychotic onset and, most of all, the duration of the period between the first onset of any psychiatric symptom and the psychotic onset (Duration of Untreated Illness).

MATERIALS AND METHODS

The study was carried out on a sample of 296 inpatients with a diagnosis of "non-affective psychosis" enrolled in "Villa dei Fiori" inpatients Clinic in Rome. The retrospective analysis was developed using clinical records and clinical interview with patients and their parents. The evaluation of the psychotic onset and of DUI was assessed with the PANSS (Positive and Negative Symptoms Scale).

RESULTS

The mean DUI is 4.7 ± 4.4 years. We found a connection between DUI and early symptoms of psycosis: depressive symptoms (4.9; DS=5.0) were most frequently observed, followed by anxiety symptoms (5.1; DS=4.8), eating disorders (5.7; DS=3.0); obsessive symptoms (4.5; DS=3.6); social withdrawal (5.9; DS=4.9); psychotic like symptoms (2.6; DS=1.3). DUI resulted lower in psychotic like symptoms than in the depressive ones.

CONCLUSION

In Italy DUI turn out to be much longer than in other Country where do exists specialized services for early intervention. For this reason seem to be necessary to explore the opportunity to develop also in Italy specialized services for adolescents and young adults at risk and at their psychotic onset.

[Management of combined psychotherapy and pharmacological treatment. A 'cross sectional' study on a selected sample of psychiatrists]

AIMS

The association between pharmacological treatment and psychotherapy is frequent. However doesn't exist any agreement or guide-line about the management of this combined therapy. Therefore we considered useful to evaluate which were the most frequent way of management of the combined therapy in a sample of 120 psychiatrists.

MATERIALS AND METHODS

A 10-items questionnaire finalized to explore the management way of the combined therapy was administered to a sample of 120 psychiatrists. A descriptive analysis of the data was made and the association between different variables was explored. The statistical analysis was performed using SPSS 13.0.

RESULTS

35% of the sample work as a private practitioner, 19.17% is involved in public health (CMHT'S). More than 50% of the sample consider the combined therapy as a effective. In the public field the combined treatment turn out to be the most utilized, opposite than in private practice. 75% of the sample manage alone the combined therapy, while 25% work in team with a colleague. 85% of the pharmacotherapy is utilized in psychosis with positive symptoms, followed by the mood disorder with psychotic symptoms. Neuroleptics are the most frequently prescribed drug.

CONCLUSIONS

The combined therapy seems to be useful when coherently with the psychotherapy theory model. The pharmacological treatment should be utilized when strictly necessary and, if is possible, the combined therapy should be managed by one psychiatrist.

Insertion of a loxP site in a size-reduced human accessory chromosome

The generation in vitro of mammalian artificial chromosomes, in view of the possibility of developing new technologies for gene therapy, is still an ambitious goal. Mammalian artificial chromosomes, to be used as cloning and expression vectors, have been constructed either by de novo synthesis or by reduction of pre-existing chromosomes. In the work here reported, we introduced a loxP sequence into the pericentromeric region of a chromosome 9-derived X-ray-reduced minichromosome, with the purpose of generating a human chromosome vector (HCV). The modified accessory chromosome is linear and mitotically stable, has lost at least 1400 kb of alpha satellite DNA and normally binds CENP-B, CENP-C and CENP-E. The efficiency of gene targeting via loxP mediated homologous recombination was tested using the histone H2B-Green Fluorescent Protein chimaeric gene as a reporter. The frequency of site-specific insertion of the exogenous sequence was found to be about 50% and to occur in a controlled way with regard to the number of copies. The expression level of the fusion protein was stable over prolonged time in culture.