Surgical treatment of recurrent retroperitoneal sarcoma in its different patterns: A 15-years' two-centers experience.

INTRODUCTION: There is limited data available regarding the role of surgery in the treatment of retroperitoneal sarcoma (RPS) recurrences. We herein report the short- and mid-term outcomes of patients who underwent surgical treatment of RPS recurrences at two Italian centers over a 15-years' experience. MATERIALS AND METHODS: From January 2005 to January 2020, 33 patients underwent surgical treatment of isolated locally recurrent RPS (LR group), locally recurrent RPS associated with the presence of distant recurrence (LR + DM group), and distant-only recurrent RPS (DM group). Only procedures performed to obtain a macroscopically radical treatment with curative intent were included. Data regarding pre-, intra-, post-operative course, and follow-up, collected in an Institutional database, were retrospectively analyzed, and compared. RESULTS: LR-group was composed of 15 patients, LR + DM group of 9 patients, and DM group of 9 patients. During the follow-up, 78.5% of the LR group, 77.8% of the DM group and 100% of the LR + DM group (p = 0.244) experienced a second recurrence. 7/11 (63.6%) patients in the LR group, 2/7 (28.5%) patients in the DM-group, and 0/9 (0.0%) patients in the LR + DM group underwent to almost one further local treatments of their recurrences (p = 0.010). No differences in the mean disease-free survival (p = 0.127), overall survival (OS) (p = 0.165) was reported among the three groups. Repeated surgery was an independent factor affecting survival in multivariate analysis (p = 0.01). CONCLUSIONS: A surgical treatment of RPS recurrences should always be taken into consideration, also in metastatic patients and/or in those who have already undergone surgery for previous RPS recurrence, because this approach may offer survival benefits.

Zebrafish Patient-Derived Xenograft Model to Predict Treatment Outcomes of Colorectal Cancer Patients.

The use of zebrafish embryos for personalized medicine has become increasingly popular. We present a co-clinical trial aiming to evaluate the use of zPDX (zebrafish Patient-Derived Xenografts) in predicting the response to chemotherapy regimens used for colorectal cancer patients. zPDXs are generated by xenografting tumor tissues in two days post-fertilization zebrafish embryos. zPDXs were exposed to chemotherapy regimens (5-FU, FOLFIRI, FOLFOX, FOLFOXIRI) for 48 h. We used a linear mixed effect model to evaluate the zPDX-specific response to treatments showing for 4/36 zPDXs (11%), a statistically significant reduction of tumor size compared to controls. We used the RECIST criteria to compare the outcome of each patient after chemotherapy with the objective response of its own zPDX model. Of the 36 patients enrolled, 8 metastatic colorectal cancer (mCRC), response rate after first-line therapy, and the zPDX chemosensitivity profile were available. Of eight mCRC patients, five achieved a partial response and three had a stable disease. In 6/8 (75%) we registered a concordance between the response of the patient and the outcomes reported in the corresponding zPDX. Our results provide evidence that the zPDX model can reflect the outcome in mCRC patients, opening a new frontier to personalized medicine.

Pattern of recurrence and survival after D2 right colectomy for cancer: is there place for a routine more extended lymphadenectomy?

BACKGROUND: Conventional Right Colectomy with D2 lymphadenectomy (RC-D2) currently represent the most common surgical treatment of right-sided colon cancer (RCC). However, whether it should be still considered a standard of care, or replaced by a routine more extended D3 lymphadenectomy remains unclear. In the present study, we aim to critically review the patterns of relapse and the survival outcomes obtained from our 11-year experience of RC-D2. METHODS: Clinical data of 489 patients who underwent RC-D2 for RCC at two centres, from January 2009 to January 2020, were retrospectively reviewed. Patients with synchronous distant metastases and/or widespread nodal involvement at diagnosis were excluded. Post-operative clinical-pathological characteristics and survival outcomes were evaluated including the pattern of disease relapse. RESULTS: We enrolled a total of 400 patients with information follow-up. Postoperative morbidity was 14%. The median follow-up was 62 months. Cancer recurrence was observed in 55 patients (13.8%). Among them, 40 patients (72.7%) developed systemic metastases, and lymph-node involvement was found in 7 cases (12.8%). None developed isolated central lymph-node metastasis (CLM), in the D3 site. The estimated 3- and 5-year relapse-free survival were 86.1% and 84.4%, respectively. The estimated 3- and 5-year cancer-specific OS were 94.5% and 92.2%, respectively. CONCLUSIONS: The absence of isolated CLM, as well as the cancer-specific OS reported in our series, support the routine use of RC-D2 for RCC. However, D3 lymphadenectomy may be recommended in selected patients, such as those with pre-operatively known CLM, or with lymph-node metastases close to the origin of the ileocolic vessels.

In Pancreatic Adenocarcinoma Alpha-Synuclein Increases and Marks Peri-Neural Infiltration.

α-Synuclein (α-syn) is a protein involved in neuronal degeneration. However, the family of synucleins has recently been demonstrated to be involved in the mechanisms of oncogenesis by selectively accelerating cellular processes leading to cancer. Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal human cancers, with a specifically high neurotropism. The molecular bases of this biological behavior are currently poorly understood. Here, α-synuclein was analyzed concerning the protein expression in PDAC and the potential association with PDAC neurotropism. Tumor (PDAC) and extra-tumor (extra-PDAC) samples from 20 patients affected by PDAC following pancreatic resections were collected at the General Surgery Unit, University of Pisa. All patients were affected by moderately or poorly differentiated PDAC. The amount of α-syn was compared between tumor and extra-tumor specimen (sampled from non-affected neighboring pancreatic areas) by using in situ immuno-staining with peroxidase anti-α-syn immunohistochemistry, α-syn detection by using Western blotting, and electron microscopy by using α-syn-conjugated immuno-gold particles. All the methods consistently indicate that each PDAC sample possesses a higher amount of α-syn compared with extra-PDAC tissue. Moreover, the expression of α-syn was much higher in those PDAC samples from tumors with perineural infiltration compared with tumors without perineural infiltration.

Robot-assisted pancreatoduodenectomy with the da Vinci Xi: can the costs of advanced technology be offset by clinical advantages? A case-matched cost analysis versus open approach.

BACKGROUND: Robot-assisted pancreatoduodenectomy (RPD) has shown some advantages over open pancreatoduodenectomy (OPD) but few studies have reported a cost analysis between the two techniques. We conducted a structured cost-analysis comparing pancreatoduodenectomy performed with the use of the da Vinci Xi, and the traditional open approach, and considering healthcare direct costs associated with the intervention and the short-term post-operative course. MATERIALS AND METHODS: Twenty RPD and 194 OPD performed between January 2011 and December 2020 by the same operator at our high-volume multidisciplinary center for robot-assisted surgery and for pancreatic surgery, were retrospectively analyzed. Two comparable groups of 20 patients (Xi-RPD-group) and 40 patients (OPD-group) were obtained matching 1:2 the RPD-group with the OPD-group. Perioperative data and overall costs, including overall variable costs (OVCs) and fixed costs, were compared. RESULTS: No difference was reported in mean operative time: 428 min for Xi-RPD-group versus 404 min for OPD, p = 0.212. The median overall length of hospital stay was significantly lower in the Xi-RPD-group: 10 days versus 16 days, p = 0.001. In the Xi-RPD-group, consumable costs were significantly higher (€6149.2 versus €1267.4, p < 0.001), while hospital stay costs were significantly lower: €5231.6 versus €8180 (p = 0.001). No significant differences were found in terms of OVCs: €13,483.4 in Xi-RPD-group versus €11,879.8 in OPD-group (p = 0.076). CONCLUSIONS: Robot-assisted surgery is more expensive because of higher acquisition and maintenance costs. However, although RPD is associated to higher material costs, the advantages of the robotic system associated to lower hospital stay costs and the absence of difference in terms of personnel costs thanks to the similar operative time with respect to OPD, make the OVCs of the two techniques no longer different. Hence, the higher costs of advanced technology can be partially compensated by clinical advantages, particularly within a high-volume multidisciplinary center for both robot-assisted and pancreatic surgery. These preliminary data need confirmation by further studies.

Minimally invasive distal pancreatectomy: a case-matched cost-analysis between robot-assisted surgery and direct manual laparoscopy.

BACKGROUND: Few studies have reported a structured cost analysis of robotic distal pancreatectomy (RDP), and none have compared the relative costs between the robotic-assisted surgery (RAS) and the direct manual laparoscopy (DML) in this setting. The aim of the present study is to address this issue by comparing surgical outcomes and costs of RDP and laparoscopic distal pancreatectomies (LDP). METHODS: Eighty-eight RDP and 47 LDP performed between January 2008 and January 2020 were retrospectively analyzed. Three comparable groups of 35 patients each (Si-RDP-group, Xi-RDP group, LDP-group) were obtained matching 1:1 the RDP-groups with the LDP-group. Overall costs, including overall variable costs (OVC) and fixed costs were compared using generalized linear regression model adjusting for covariates. RESULTS: The conversion rate was significantly lower in the Si-RDP-group and Xi-RDP-group: 2.9% and 0%, respectively, versus 14.3% in the LDP-group (p = 0.045). Although not statistically significant, the mean operative time was lower in Xi-RDP-group: 226 min versus 262 min for Si-RDP-group and 247 min for LDP-group. The overall post-operative complications rate and the length of hospital stay (LOS) were not significantly different between the three groups. In LDP-group, the LOS of converted cases was significantly longer: 15.6 versus 9.8 days (p = 0.039). Overall costs of LDP-group were significantly lower than RDP-groups, (p < 0.001). At multivariate analysis OVC resulted no longer statistically significantly different between LDP-group and Xi-RDP-group (p = 0.099), and between LDP-group and the RDP-groups when the spleen preservation was indicated (p = 0.115 and p = 0.261 for Si-RDP-group and Xi-RDP-group, respectively). CONCLUSIONS: RAS is more expensive than DML for DP because of higher acquisition and maintenance costs. The flattening of these differences considering only the variable costs, in a high-volume multidisciplinary center for RAS, suggests a possible optimization of the costs in this setting. RAS might be particularly indicated for minimally invasive DP when the spleen preservation is scheduled.

Detailing the ultrastructure's increase of prion protein in pancreatic adenocarcinoma.

BACKGROUND: Recent evidences have shown a relationship between prion protein (PrPc) expression and pancreatic ductal adenocarcinoma (PDAC). Indeed, PrPc could be one of the markers explaining the aggressiveness of this tumor. However, studies investigating the specific compartmentalization of increased PrPc expression within PDAC cells are lacking, as well as a correlation between ultrastructural evidence, ultrastructural morphometry of PrPc protein and clinical data. These data, as well as the quantitative stoichiometry of this protein detected by immuno-gold, provide a significant advancement in understanding the biology of disease and the outcome of surgical resection. AIM: To analyze quantitative stoichiometry and compartmentalization of PrPc in PDAC cells and to correlate its presence with prognostic data. METHODS: Between June 2018 and December 2020, samples from pancreatic tissues of 45 patients treated with pancreatic resection for a preoperative suspicion of PDAC at our Institution were collected. When the frozen section excluded a PDAC diagnosis, or the nodules were too small for adequate sampling, patients were ruled out from the present study. Western blotting was used to detect, quantify and compare the expression of PrPc in PDAC and control tissues, such as those of non-affected neighboring pancreatic tissue of the same patient. To quantify the increase of PrPc and to detect the subcellular compartmentalization of PrPc within PDAC cells, immuno-gold stoichiometry within specific cell compartments was analyzed with electron microscopy. Finally, an analysis of quantitative PrPc expression according to prognostic data, such as cancer stage, recurrence of the disease at 12 mo after surgery and recurrence during adjuvant chemotherapy was made. RESULTS: The amount of PrPc within specimen from 38 out of 45 patients was determined by semi-quantitative analysis by using Western blotting, which indicates that PrPc increases almost three-fold in tumor pancreatic tissue compared with healthy pancreatic regions [242.41 ± 28.36 optical density (OD) vs 95 ± 17.40 OD, P < 0.0001]. Quantitative morphometry carried out by using immuno-gold detection at transmission electron microscopy confirms an increased PrPc expression in PDAC ductal cells of all patients and allows to detect a specific compartmentalization of PrPc within tumor cells. In particular, the number of immuno-gold particles of PrPc was significantly higher in PDAC cells respect to controls, when considering the whole cell (19.8 ± 0.79 particles vs 9.44 ± 0.45, P < 0.0001). Remarkably, considering PDAC cells, the increase of PrPc was higher in the nucleus than cytosol of tumor cells, which indicates a shift in PrPc compartmentalization within tumor cells. In fact, the increase of immuno-gold within nuclear compartment exceeds at large the augment of PrPc which was detected in the cytosol (nucleus: 12.88 ± 0.59 particles vs 5.12 ± 0.32, P < 0.0001; cytosol: 7.74. ± 0.44 particles vs 4.3 ± 0.24, P < 0.0001). In order to analyze the prognostic impact of PrPc, we found a correlation between PrPc expression and cancer stage according to pathology results, with a significantly higher expression of PrPc for advanced stages. Moreover, 24 patients with a mean follow-up of 16.8 mo were considered. Immuno-blot analysis revealed a significantly higher expression of PrPc in patients with disease recurrence at 12 mo after radical surgery (360.71 ± 69.01 OD vs 170.23 ± 23.06 OD, P = 0.023), also in the subgroup of patients treated with adjuvant CT (368.36 ± 79.26 OD in the recurrence group vs 162.86 ± 24.16 OD, P = 0.028), which indicates a correlation with a higher chemo-resistance. CONCLUSION: Expression of PrPc is significantly higher in PDAC cells compared with control, with the protein mainly placed in the nucleus. Preliminary clinical data confirm the correlation with a poorer prognosis.

Zebrafish Patient-Derived Xenografts Identify Chemo-Response in Pancreatic Ductal Adenocarcinoma Patients.

It is increasingly evident the necessity of new predictive tools for the treatment of pancreatic ductal adenocarcinoma in a personalized manner. We present a co-clinical trial testing the predictiveness of zPDX (zebrafish patient-derived xenograft) for assessing if patients could benefit from a therapeutic strategy (ClinicalTrials.gov: XenoZ, NCT03668418). zPDX are generated xenografting tumor tissues in zebrafish embryos. zPDX were exposed to chemotherapy regimens commonly used. We considered a zPDX a responder (R) when a decrease ≥50% in the relative tumor area was reported; otherwise, we considered them a non-responder (NR). Patients were classified as Responder if their own zPDX was classified as an R for the chemotherapy scheme she/he received an adjuvant treatment; otherwise, we considered them a Non-Responder. We compared the cancer recurrence rate at 1 year after surgery and the disease-free survival (DFS) of patients of both groups. We reported a statistically significant higher recurrence rate in the Non-Responder group: 66.7% vs. 14.3% (p = 0.036), anticipating relapse/no relapse within 1 year after surgery in 12/16 patients. The mean DFS was longer in the R-group than the NR-group, even if not statistically significant: 19.2 months vs. 12.7 months, (p = 0.123). The proposed strategy could potentially improve preclinical evaluation of treatment modalities and may enable prospective therapeutic selection in everyday clinical practice.

Associations between pancreatic expression quantitative traits and risk of pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal cancers. Its poor prognosis is predominantly due to the fact that most patients remain asymptomatic until the disease reaches an advanced stage, alongside the lack of early markers and screening strategies. A better understanding of PDAC risk factors is essential for the identification of groups at high risk in the population. Genome-wide association studies (GWAS) have been a powerful tool for detecting genetic variants associated with complex traits, including pancreatic cancer. By exploiting functional and GWAS data, we investigated the associations between polymorphisms affecting gene function in the pancreas (expression quantitative trait loci, eQTLs) and PDAC risk. In a two-phase approach, we analysed 13 713 PDAC cases and 43 784 controls and identified a genome-wide significant association between the A allele of the rs2035875 polymorphism and increased PDAC risk (P = 7.14 × 10-10). This allele is known to be associated with increased expression in the pancreas of the keratin genes KRT8 and KRT18, whose increased levels have been reported to correlate with various tumour cell characteristics. Additionally, the A allele of the rs789744 variant was associated with decreased risk of developing PDAC (P = 3.56 × 10-6). This single nucleotide polymorphism is situated in the SRGAP1 gene and the A allele is associated with higher expression of the gene, which in turn inactivates the cyclin-dependent protein 42 (CDC42) gene expression, thus decreasing the risk of PDAC. In conclusion, we present here a functional-based novel PDAC risk locus and an additional strong candidate supported by significant associations and plausible biological mechanisms.

Prognostic impact of conservative surgery for pancreatic IPMNs.

BACKGROUND: The extent of pancreatic resection for intraductal papillary mucinous neoplasms (IPMNs) remains an unresolved issue. The study aims at analyzing the prognostic impact of conservative surgery (CS) i.e. of pancreatoduodenectomy or distal pancreatectomy, versus total pancreatectomy (TP), for pancreatic IPMNs. METHODS: We retrospectively analyzed and compared data of patients who had undergone pancreatic resection for IPMNs at our center between November 2007 and April 2019. Patients were divided into two main groups based on the extent of surgery: TP-group and CS-group. Subsequently, the perioperative and the long-term outcomes were compared. Moreover, a sub-group analysis of patients with IPMN alone and patients with malignant IPMN, based on preoperative indications to surgery and post-operative histopathological findings, was also performed. RESULTS: Fifty-three patients were included in the TP-group and 73 in the CS-group. In 50 (39.7%) cases the frozen section changed the pre-operative surgical planning, with an extension of the pancreatic resection, in 43 (34.1%) cases up to a total pancreatectomy. Twenty-six patients (20.6%) with low-grade dysplasia at the frozen section underwent CS, while twenty (15.8%) underwent TP. Comparing these two sub-groups no differences were found in surgical IPMN recurrence, nor progression. The rate of overall postoperative complications was 56.6% in the TP-group and 57.5% in the CS-group (p = 0.940). Fifteen patients (20.5%) developed diabetes in the CS-group. None of the patients treated with CS developed a surgical IPMN recurrence or progression during the follow-up period. Comparing OS and DFS of the two groups, we did not find any statistically significant difference (p = 0.619 and 0.315). CONCLUSION: A timely CS can be considered an appropriate and valid strategy in the surgical treatment of the majority of pancreatic IPMNs, as it can avoid the serious long-term metabolic consequences of TP in patients with a long-life expectancy. On the contrary, TP remains mandatory in case of PDAC or high-risk features involving the entire gland.

Tissue microarray-chip featuring computerized immunophenotypical characterization more accurately subtypes ampullary adenocarcinoma than routine histology.

BACKGROUND: Ampullary adenocarcinomas (AACs) are heterogeneous tumors currently classified into three important sub-classes (SC): Intestinal (INT), Pancreato-Biliary (PB) and Mixed-Type (MT). The different subgroups have similar clinical presentation and are treated by pancreatoduodenectomy with curative intent. However, they respond differently to chemotherapy and have different prognostic outcomes. The SC are often difficult to identify with conventional histology alone. The clinical outcome of all three remains unclear, particularly for MT. AIM: To identify two main subtypes of AACs, using an immunohistochemical (IHC) score based on CDX2, CK7 and CK20. METHODS: Tissue samples from 21 patients who had undergone resection of AAC were classified by HE histology and IHC expression of CDX2, CK7 and CK 20. An IHC score was obtained for each marker by counting the number of positive cells (0 = no stained cells; 1 < 25%; 2 < 50% and 3 > 50%) and their intensity (1 = weak; 2 = moderate and 3 = strong). A global score (GS) was then obtained by summation of the IHC scores of each marker. The MT tumors were grouped either with the INT or PB group based on the predominant immuno-molecular phenotype, obtaining only two AACs subtypes. The overall survival in INT and PB patients was obtained by Kaplan-Meier methods. RESULTS: Histological parameters defined the AACs subtypes as follows: 15% INT, 45% PB and 40% MT. Using IHC expression and the GS, 75% and 25% of MT samples were assigned to either the INT or the PB group. The mean value of the GS was 9.5 (range 4-16). All INT samples had a GS above the average, distinct from the PB samples which had a GS score significantly below the average (P = 0.0011). The INT samples were identified by high expression of CDX2 and CK20, whereas PB samples exhibited high expression of CK7 and no expression of CK20 (P = 0.0008). The INT group had a statistically significant higher overall survival than in the PB group (85.7 mo vs 20.3 mo, HR: 8.39; 95%CI: 1.38 to 18.90; P = 0.0152). CONCLUSION: The combination of histopathological and molecular criteria enables the classification of AACs into two clinically relevant histo-molecular phenotypes, which appear to represent distinct disorders with potentially significant changes to the current therapeutic strategies.

Renal cell carcinoma: The role of radical surgery on different patterns of local or distant recurrence.

INTRODUCTION: With the increasing reliance on targeted therapies and immunotherapy, no standard management strategy is today available for the treatment of locally, distant, or both renal cell carcinoma (RCC) recurrences, and their surgical treatment seems to play a crucial role. We report the 20-year experience of our center evaluating the short- and long-term outcomes of patients undergone surgical resection of RCC recurrences, and the possible role of repeated surgical resections of RCC recurrences. MATERIALS AND METHODS: From January 1999 to January 2019, 40 patients underwent surgical resection of isolated locally recurrent RCC (iLR-RCC-group), locally recurrent RCC associated with the presence of distant recurrence (LR-DR-RCC-group), and distant-only recurrent RCC (DR-RCC-group). Data regarding pre-, intra-, post-operative course, and follow-up, prospectively collected in an institutional database, were retrospectively analyzed and compared. RESULTS: iLR-RCC-group was composed of 9 patients, LR-DR-RCC-group of 6 patients, and DR-RCC-group of 25 patients. The recurrence rate was 55.6% (5/9 patients) in iLR-RCC-group, 50% (3/6 patients) in LR-DR-RCC-group, and 44% (11/25) patients in DR-RCC-group, p = 0.830. 3/5 (60%) patients in iLR-RCC-group, 2/3 (66.7%) patients in LR-DR-RCC-group, and 7/11 (63.6%) patients in DR-RCC group underwent to almost one further local treatments of their recurrences, respectively (p = 0.981). No differences in the mean disease-free survival (p = 0.384), overall survival (OS) (p = 0.881), and cancer-specific survival (p = 0.265) were reported between the three groups. In DR-RCC-group, patients who underwent further local treatments of new recurrences presented a longer OS: 150.7 versus 66.5 months (p = 0.004). CONCLUSIONS: A surgical resection of RCC recurrences should be always taken in consideration, also in metastatic patients and/or in those who have already undergone surgery of previous RCC recurrence, whenever radicality is still possible, because this approach may offer a potentially long survival.

The occurrence of prion protein in surgically resected pancreatic adenocarcinoma.

BACKGROUND: Among the several new targets for the comprehension of the biology of pancreatic ductal adenocarcinoma (PDAC), Prion proteins (PrPc) deserve particular mention, since they share a marked neurotropism. Actually, PrPc could have also a role in tumorigenesis, as recently demonstrated. However, only few in vitro studies in cell cultures showed the occurrence of PrPc in PDAC cells. We aim to evaluate the presence of PrPc in vivo in PDAC tissues as a potential new biomarker. METHODS: Samples from tumors of 23 patients undergone pancreatic resections from July 2018 to May 2020 at our institution were collected and analyzed. Immunohistochemistry and western blotting of PDAC tissues were compared with control tissues. Immunohistochemistry was used also to evaluate the localization of PrPc and of CD155, a tumoral stem-cell marker. RESULTS: All cases were moderately differentiated PDAC, with perineural invasion (PNI) in 19/23 cases (83%). According to western-blot analysis, PrPc was markedly expressed in PDAC tissues (273.5 ± 44.63 OD) respect to controls (100 ± 28.35 OD, p = 0.0018). Immunohistochemistry confirmed these findings, with higher linear staining of PrPc in PDAC ducts (127.145 ± 7.56 µm vs 75.21 ± 5.01 µm, p < 0.0001). PrPc and CD155 exactly overlapped in ductal tumoral cells, highlighting the possible relationship of PrPc with cancer stemness. Finally, PrPc expression related with cancer stage and there was a potential correspondence with PNI. CONCLUSIONS: Our work provides evidence for increased levels of PrPc in PDAC. This might contribute to cancer aggressiveness and provides a potentially new biomarker. Work is in progress to decipher clinical implications.

Use of zebrafish embryos as avatar of patients with pancreatic cancer: A new xenotransplantation model towards personalized medicine.

BACKGROUND: The response to chemotherapy treatment of patients with pancreatic ductal adenocarcinoma (PDAC) is difficult to predict and the identification of patients who most likely will benefit from aggressive chemotherapy approaches is crucial. The concept of personalized medicine has emerged in the last years with the objective to tailor the medical treatment to the individual characteristics of each patient, and particularly to the tumor biology of each patient. The need for in-vivo xenotransplantation models for cancer patients has increased exponentially, and for this reason zebrafish avatars have gained popularity. Preliminary studies were conducted also with PDAC tissue. AIM: To develop a simple, not expensive, diffusible zebrafish embryo model as avatar for patients affected by PDAC. METHODS: Tumor tissue was taken from the surgical specimen by the histopathologist. After its fragmentation into small pieces, they are stained with CM-Dil. Small pieces of stained tissue were transplanted into the yolk of wt AB zebrafish embryos with a glass capillary needle. Embryos were incubated at 35 °C in E3 medium supplemented with 1% Pen/Strep in the presence or absence of drugs for the following days in respect of the treatment plan (Gemcitabine; Gemcitabine and Oxaliplatin; Gemcitabine and nab-Paclitaxel; 5-Fluorouracil and Folinic acid and Oxaliplatin and Irinotecan). The response of zebrafish xenografts to the chemotherapy options has been analyzed by monitoring the fluorescent stained area at 2 h post injection (hpi), 1 d and 2 d post injection (dpi). In each time point, the mean size of the stained area was measured by ImageJ and it was normalized with respect to the 1 dpi time point mean relative tumor area (RTA). We evaluated the effect of the chemotherapy exposition comparing the mean RTA of each treated subgroup and the control group and evaluating the percentage reduction of the mean RTA by comparing each treated subgroup with the control group. RESULTS: Between July 2018 and October 2019, a total of 15 patients with pancreatic cancer were prospectively enrolled. In all cases, it was possible to take a fragment of the tumor from the surgical specimen for the xenotransplantation in the zebrafish embryos. The histological examination confirmed the presence of a PDAC in all cases. In absence of chemotherapy (control group), over time the Dil-stained area showed a statistically significant increase in all cases. A statistically significant reduction of the mean RTA in the treated subgroups for at least one chemotherapy scheme was reported in 6/15 (40%) cases. The analysis of the percentage reduction of the RTA in treated subgroups in comparison to the control group revealed the presence of a linear relationship in each subgroup between the percentage reduction of the RTA and the number of cases reporting each percentage threshold considered for the analysis. CONCLUSION: Our model seems to be effective for the xenotransplantation of PDAC tissue and evaluation of the effect of each chemotherapy scheme on the xenotransplanted tumor tissue.

A Model of a Zebrafish Avatar for Co-Clinical Trials.

Animal "avatars" and co-clinical trials are being developed for possible use in personalized medicine in oncology. In a co-clinical trial, the cancer cells of the patient's tumor are xenotransplanted into the animal avatar for drug efficacy studies, and the data collected in the animal trial are used to plan the best drug treatment in the patient trial. Zebrafish have recently been proposed for implementing avatar models, however the lack of a general criterion for the chemotherapy dose conversion from humans to fish is a limitation in terms of conducting co-clinical trials. Here, we validate a simple, reliant and cost-effective avatar model based on the use of zebrafish embryos. By crossing data from safety and efficacy studies, we found a basic formula for estimating the equivalent dose for use in co-clinical trials which we validated in a clinical study enrolling 24 adult patients with solid cancers (XenoZ, NCT03668418).

Pancreatic resections for metastases: A twenty-year experience from a tertiary care center.

BACKGROUND: Literature data about pancreatic resections for metastases are limited to small series, so that the role of surgery in this setting remains unclear. We herein report our experience from a tertiary care center, analyzing the outcomes of patients who underwent pancreatic resections for metastases and discussing the role of surgical resection in their management. MATERIALS AND METHODS: From January 1999 to January 2019, 26 patients underwent pancreatic resections for metastases from renal cell carcinoma (RCC-group) or other primitive tumors (non-RCC-group). Details regarding pre-, intra-, post-operative course, and follow-up, prospectively collected in a database of pancreatic resection, were retrospectively analyzed and compared. RESULTS: RCC-group was composed of 21 patients, non-RCC-group of 5 patients. RCC-group presented a longer disease-free interval: 96.4 vs. 5.4 months (p < 0.001). In 9/21 patients (42.9%) of RCC-group the surgical resection of other organs or vascular structures was performed, while in non-RCC-group pancreatic resection alone was performed in all cases, p = 0.070. No local recurrence was reported in all cases. The systemic recurrence rate was 42.9% (9/21 patients) in RCC-group and 80% (4/5 patients) in non-RCC-group, p = 0.135. RCC-group presented a longer DFS and OS: 107.5 vs. 25.2 months (p = 0.002), and 109.1 vs. 36.2 months (p = 0.016), respectively. CONCLUSIONS: Radical pancreatic resection may confer a survival benefit for RCC metastases, while for other primitive tumors it should be applied more selectively. For RCC pancreatic metastases, an aggressive surgical approach, even in patient with locally advanced tumors, or associated extra-pancreatic localizations, or recurrent metastases should be taken in consideration.

Robotic-assisted surgery for colorectal liver metastasis: A single-centre experience.

Background: Although minimally invasive surgery (MIS) of the liver is increasingly widespread, its role in the treatment of colorectal liver metastasis (CRLM) remains uncertain. In this setting, the role of robotic-assisted surgery (RAS) has not been significantly evaluated yet. The aim of this study was to report our experience with RAS for treatment of CRLM. Material and Methods: Prospectively collected surgical and oncologic data on all of the robotic-assisted liver resections for CRLM performed at our centre were retrieved from the institutional database and retrospectively analysed. Intra-operative ultrasound (US) was obtained with a dedicated robotic probe using the TilePro™ function. Results: Twenty patients underwent robotic-assisted resection of CRLM between May 2012 and April 2018. Six patients (30%) had multiple synchronous CRLM resections (median = 2; range 2-4). The tumour size averaged 3.0 ± 1.8 cm. All of the lesions were removed using a parenchymal-sparing approach, with R0 resection margins. Mean hospital stay was 4.7 ± 1.8 days. The mean follow-up was 22.5 ± 19.5 months. During the study period, there were no local recurrences, while 9 patients (45%) developed new systemic metastasis. All patients are still alive as of September 2018 with 1- and 3-year disease-free survival of 89.5% and 35.8%, respectively. Conclusions: In our experience, RAS for CRLM surgical treatment was feasible and played a positive role even in patients with multiple metastases and previous or synchronous surgery. RAS seemed to be oncologically effective in this setting, as no patients experienced local relapse in the treated area.

Robotic-assisted versus open left pancreatectomy for cystic tumours: A single-centre experience.

BACKGROUND: Cystic pancreatic lesions (CPLs) are being identified increasingly, and some benefit from surgical treatment. With the increasing use of robotic-assisted surgery (RAS) for neoplasms of the pancreas, the aim of the present comparative study is to establish whether the RAS offered any advantages over conventional open surgery (OS) in the management of CPLs. PATIENTS AND METHODS: Twenty-seven out of 37 robot-assisted left-sided pancreatectomy (LSP) performed between January 2010 and April 2017 were carried out for CPLs. The surgical outcome and histopathology were compared retrospectively with a control group of 27 patients who had undergone open LSP for CPLs, selected using a one-to-one case-matched methodology (OS-Group) from the prospectively collected institutional database. RESULTS: The spleen was preserved in a significantly higher percentage of patients in the RAS-group (63% vs. 33.3%,P < 0.05). There was no difference in the post-operative course (pancreatic fistula and morbidity) between the two groups. The median post-operative hospital stay was significantly shorter in the RAS-group: 8 days (range 3-25) versus 12 days (range 7-26) in the OS-group (P < 0.01). No conversion to open approach was reported in the RAS-group. CONCLUSIONS: Robotically assisted LSP is a safe and effective procedure. It is accompanied by a significantly higher spleen preservation rate compared to the open approach. In addition, because of the reduced trauma, RAS incurred a shorter post-operative hospital stay and faster return to full recovery, particularly important in patients undergoing surgery for relative indications. However, these benefits of RAS for LSP require confirmation by prospective randomised controlled studies.

Angiosarcomaafteradjuvantradiotherapy in high-risksquamouscell carcinoma of the vulva: a case report.

Squamous cell carcinoma of the vulva represents 3-5% of gynecological cancers. The incidence is higher in postmenopausal patients; the mean age of women with vulvar cancer is between 64 and 70 years. Radiotherapy plays an increasing role in the treatment of high-risk squamous cell carcinoma of the vulva; associated with surgery it significantly improves prognosis but is also associated with serious late side-effects, such as secondary malignancies. We describe a case of a 75-year-old woman who underwent deep total vulvectomy with inguinal-femoral lymphadenectomy for high-risk, keratinizing variant HPV-negative, squamous cell carcinoma of the vulva, followed by adjuvant concomitant chemo-radiotherapy, at the University Hospital of Pisa in February 2013. Five years later she developed a very large angiosarcoma in the right abdominal wall, at the edge of the previous radiotherapy field, and underwent radical surgery. After four months, she developed bone metastasis of angiosarcoma, also treated with surgery. This experience shows that the use of new technologies allows the delivery of high doses of radiotherapy, significantly correlated with a better prognosis, but also associated with fortunately rare morbidity, such as radiation-induced angiosarcoma. Due to the presence of long, mostly post-menopausal survivors among irradiated patients, screening for second malignancies must be developed for selected high-risk survivor groups.