R0 Resection Group Research Articles

Wide surgical margins may be necessary to reduce recurrence and mortality in patients with localized periosteal chondrosarcoma: retrospective analysis of twenty three patients and literature meta-analysis.

Periosteal chondrosarcoma (PCS) is the rarest subtype of chondrosarcoma and is recognized as a low-grade malignant tumour, reported to have an 88% ten year overall survival rate. The relationship between surgical margins and clinical outcome is inconsistent; some authors claim that PCS can be successfully treated with marginal resection and others report more local recurrence and distant metastasis with marginal compared to wide resection. This study was intended to report the treatment and prognosis of localized PCS patients from the Japanese National Bone and Soft Tissue Tumor Registry database and to perform a systematic review of the literature to determine the relationship between surgical margins and rates of local recurrence, distant metastasis, and mortality. Twenty-three patients with pathologically-diagnosed PCS between 2006 and 2022 from the Japanese National Bone and Soft Tissue Tumor Registry database were retrospectively analyzed. Of the 105 studies found through a systematic search using Pubmed, Embase, and Cochrane Central Register of Controlled Trials databases, nine studies were ultimately included. The local recurrence rate after R0 resection was 2.5% (3/118 patients) and after R1 resection was 33.3% (11/33 patients) (p < 0.001). The distant metastasis rate in the R0 resection group was 5.9% (7/118 patients) and in the R1 resection group was 27.3% (9/33 patients) (p = 0.010). Mortality following R0 resection was 4.2% (5/118 patients) but after R1 resection was 18.2% (6/33 patients) (p = 0.040). Wide resection may be necessary for localized PCS to prevent local recurrence and distant metastasis and improve survival.

Chemoradiotherapy and Subsequent Immunochemotherapy as Conversion Therapy in Unresectable Locally Advanced Esophageal Squamous Cell Carcinoma: A Phase II NEXUS-1 Trial.

This phase II trial investigated the safety and efficacy of chemoradiotherapy (CRT) followed by immunochemotherapy (iCT) and surgery in unresectable locally advanced esophageal squamous cell carcinoma (ESCC). Patients with unresectable locally advanced ESCC received radiotherapy (50 Gy/25f, 5 days/week) and nab-paclitaxel (100 mg on day 1/week) plus cisplatin (25 mg/m2 on day 1/week) for 5 weeks, followed by tislelizumab (200 mg on day 1/cycle) plus chemotherapy (nab-paclitaxel 150 mg/m2 and cisplatin 75 mg/m2 on day 2/cycle) for two 21-day cycles. Patients who converted to resectable underwent surgery 2 to 4 weeks afterward. The primary endpoint was a 1-year progression-free survival (PFS) rate. Thirty patients were enrolled and underwent CRT (median follow-up: 21 months), of whom 24 received iCT. Twenty (66.7%) patients achieved resectability (R0: 95.2%; pathologic complete response: 65.0%; major pathologic response: 90.0%). One-year PFS and overall survival (OS) rates were 79.4% and 89.6%, respectively. The R0 resection group exhibited longer PFS (median, not reached vs. 8.4 months; HR = 0.28; 95% confidence interval, 0.08-0.84; P = 0.02) and OS (median, not reached vs. 19.2 months; HR = 0.18; 95% confidence interval, 0.04-0.73; P < 0.01) than the nonsurgery group. Grade 3 to 4 adverse events were observed in 11 (11/30, 36.7%) patients, and immune-related pneumonitis was observed in 5 (5/24, 20.8%) patients. Post-CRT minimal residual disease before surgery was associated with unfavorable PFS and OS. Our study met the primary endpoint. Conversion CRT and subsequent iCT followed by surgery was a promising treatment strategy for unresectable locally advanced ESCC.

Comparing Survival of Perihilar Cholangiocarcinoma After R1 Resection Versus Palliative Chemotherapy for Unresected Localized Disease

BackgroundResection of perihilar cholangiocarcinoma (pCCA) is a complex procedure with a high risk of postoperative mortality and early disease recurrence. The objective of this study was to compare patient characteristics and overall survival (OS) between pCCA patients who underwent an R1 resection and patients with localized pCCA who received palliative systemic chemotherapy.MethodsPatients with a diagnosis of pCCA between 1997–2021 were identified from the European Network for the Study of Cholangiocarcinoma (ENS-CCA) registry. pCCA patients who underwent an R1 resection were compared with patients with localized pCCA (i.e., nonmetastatic) who were ineligible for surgical resection and received palliative systemic chemotherapy. The primary outcome was OS.ResultsOverall, 146 patients in the R1 resection group and 92 patients in the palliative chemotherapy group were included. The palliative chemotherapy group more often underwent biliary drainage (95% vs. 66%, p < 0.001) and had more vascular encasement on imaging (70% vs. 49%, p = 0.012) and CA 19.9 was more frequently >200 IU/L (64 vs. 45%, p = 0.046). Median OS was comparable between both groups (17.1 vs. 16 months, p = 0.06). Overall survival at 5 years after diagnosis was 20.0% with R1 resection and 2.2% with chemotherapy. Type of treatment (i.e., R1 resection or palliative chemotherapy) was not an independent predictor of OS (hazard ratio 0.76, 95% confidence interval 0.55–1.07).ConclusionsPalliative systemic chemotherapy should be considered instead of resection in patients with a high risk of both R1 resection and postoperative mortality.

Clinicopathological features of cholangiolocarcinoma and impact of tumor heterogeneity on prognosis: A single institution retrospective study.

Cholangiolocarcinoma (CLC) is an extremely rare tumor classified as a subtype of small duct-type intrahepatic cholangiocarcinoma (iCCA). There are few detailed reports on CLC and the prognostic impact of tumor heterogeneity is not clear. Between April 2006 and June 2022, of the 774 primary liver cancer resection cases who presented at Kanazawa University Hospital, 14 patients were pathologically diagnosed with CLC through immunohistochemical analysis of their molecular and biological features. Clinicopathological features and prognoses were evaluated retrospectively. Additionally, tumor heterogeneity was assessed and tumors were classified into pure and partial types according to the CLC component proportion in a single tumor. Chronic liver disease was observed in nine patients (64.3%). All tumors were mass-forming, and pathological R0 resection was achieved in 11 patients (78.6%). Tumor heterogeneity was classified as pure in 11 (78.6%) and partial in three (21.4%) patients. The median follow-up was 59.5 months (12-114 months). There was no difference in the 5-year disease-specific survival rates between the pure and partial (90.0% vs. 100.0%; P=0.200) types, but rates were significantly higher in the R0 resection group compared with those in the R1 resection group (100.0% vs. 50.0%; P=0.025). In conclusion, these results suggest that it is important for CLC patients to achieve curative resection, and CLC may have a good prognosis regardless of the proportion of CLC components in a single tumor.

Low Expectancy of Conversion Surgery with R0 Resection in Patients with CEA > 5.0 ng/mL at the Initial RECIST Evaluation for Metastatic Gastric Cancer.

This retrospective study examined early the predictive factors for successful conversion surgery (CS) with R0 resection in patients with metastatic gastric cancer (MGC) who underwent systemic chemotherapy. This study included 204 patients diagnosed with metastatic gastric adenocarcinoma, who received chemotherapy between 2009 and 2019. Of these patients, 31 (15%) underwent CS with R0 resection. The incidence of CS with R0 resection was not affected by the volume of metastatic lesions or the presence of peritoneal metastasis. The overall survival time of the CS with R0 resection group was significantly longer than that of the non-CS group (hazard ratio, 0.12; 95% confidence interval, 0.07-0.23; p < 0.0001), with a 5 year overall survival rate of 50.2%. Multivariate analysis of 150 patients, excluding those with disease progression until the initial Response Evaluation Criteria in Solid Tumors (RECIST) evaluation, showed that carcinoembryonic antigen > 5.0 ng/mL at the initial RECIST evaluation was an independent, significant, and unfavorable predictor of CS with R0 resection (odds ratio, 0.21; p = 0.0108), whereas systemic chemotherapy with trastuzumab for HER2-positive cancer was a favorable factor (odds ratio, 4.20; p = 0.0119). Monitoring serum carcinoembryonic antigen levels during chemotherapy may be a useful predictor of the CS implementation in patients with MGC.

Analysis of survival factors after hepatic resection for colorectal cancer liver metastases: Does the R1 margin matter?

The effect of liver margin on colorectal cancer liver metastases (CRLM) after hepatectomy has been controversial. In this study, we conducted a postoperative follow-up study of 205 patients with CRLM to clarify whether a positive margin is significant and to define the risk factors affecting CRLM survival. The data of 205 patients with CRLM who underwent surgical treatment at the Third Hospital of Peking University in the Department of General Surgery from January 2009 to December 2020 were retrospectively analyzed. The general data, surgical data and postoperative follow-up of the patients were statistically analyzed. There were 130 cases (63.4%) of R0 resection and 75 cases (36.6%) of R1 resection. There were 136 males and 69 females, age 61 ± 11 years, and body mass index (BMI 24.5 ± 3.3 kg/m2). The overall survival rates at 1, 3, and 5 years for the entire cohort were 93.4%, 68.4%, and 45.5% in the R0 resection group vs. 93.2%, 53.7%, and 42% in the R1 resection group, respectively, which were not statistically significant (P = 0.520). The 1-, 3-, and 5-year disease-free survival rates of 63.2%, 33.3%, and 29.7% were significantly better in the R0 resection group than in the R1 resection group of 47.9%, 22.7%, and 17.7% (P = 0.016), respectively. After multivariable analysis, carbohydrate antigen 19-9 (CA19-9) > 39 U/ml (HR = 2.29, 95% CI: 1.39-3.79, P = 0.001), primary tumor perineural invasion (HR = 1.78, 95% CI: 1.01-3.13, P = 0.047), and BMI > 24 kg/m2 (HR = 1.75, 95% CI: 1.05-2.93, P = 0.033) were independently associated with poorer overall patient survival. The number of liver metastases >2 (HR = 1.65, 95% CI: 1.10-2.47, P = 0.016), the maximum diameter of metastases ≥50 mm (HR = 1.67, 95% CI: 1.06-2.64, P = 0.026), and vascular invasion of the primary tumor (HR = 1.65, 95% CI: 1.03-2.64, P = 0.038) were also independently associated with poorer disease-free survival. In patients undergoing hepatectomy for CRLM, the negative effect of the R1 margin should be downplayed, and although the disease-free survival of the R1 margin is shorter than that of the R0 margin, it has no impact on overall survival. To improve overall survival, extra attention should be given to the factors of preoperative BMI, preoperative CA19-9, and the presence of perineural invasion of the primary tumor.

480. OUTCOMES OF ADJUVANT LOCAL TREATMENT AFTER ESOPHAGEAL SURGERY WITH POSITIVE RESECTION MARGIN IN INTRATHORACIC ANASTOMOSIS

Abstract Esophageal cancer is aggressive diseases requiring surgery as an essential part of treatment. To achieve increased overall survival, complete resection (R0) is preferred. In some case, however, we encounter positive resection margin (R1). Further resection will be required, but sometimes it is difficult to do additional procedure because of various reasons, especially the highest location of anastomosis. Hypothesis of study is that R1 resection with adjuvant local therapy shows comparable result with R0 resection in intrathoracic anastomosis From 2000 to 2017, total 2723 patients received the esophagectomy and mediastinal lymph node dissection for esophageal cancer. R0 resection was 1701, and R1 resection was 76 patients. Patients who received distal esophagectomy (n=56) and lack of information about adjuvant therapy (n=24) were excluded Because of differences in some variables, we conducted 2:1 propensity score matching to reduce differences between groups. Comparison of R1 resection group with adjuvant local therapy to R0 resection group is conducted Overall survival (OS) and recurrence free survival (RFS) were estimated with Kaplan-Meier method. 76 patients were identified with R1 resection. Of those patients, 30 patients showed positive proximal resection margin from frozen section during surgery. When compared to R0 resection group (including patients with adjuvant treatment), OS and RFS were statistically lower in R1 resection group (p=0.03 and 0.023, respectively) When comparing R1 with adjuvant local treatment group to R0 resection group, there were no statistical differences in both OS and RFS.(p=0.13 and 0.22, respectively) In R1 resection group, adjuvant local treatment group show favorable result compared to non-local treatment group, but there were no statistical differences in OS and RFS.(p=0.26 and 0.17, respectively) R1 resection with proper adjuvant local treatment enable us to achieve comparable result with R0 resection group in intrathoracic anastomosis When anastomosis is made at the highest level of thorax (i.e. thoracic inlet level), it is not easy to perform additional intrathoracic resection. If it is difficult to do further resection when resection margin is positive, adjuvant local treatment after surgery can be one reasonable option to improve patient’s survival or minimize disease recurrence

The Future Perspectives of Redefining the Resection Margin Status in Different Cancers of Pancreas

Background: The interest towards the assessment of circumferential resection margins(CRM) in pancreatic cancers has been evolving over last years. Whilst several studies investigated the influence of R1-resections on survival, not many studies evaluated the prognostic value of each resection margin. In this study, we examined the different resection margins to better understand their prognostic implications on overall survival.&#x0D; Methods: This prospective study included a cohort of patients who had pancreaticoduodenectomy for cancer purposes at our institution from 2008 till 2013. Median follow-up was 6 years. Involved margins in R1-resections were further classified into anatomical margins (anterior, posterior and circumferential margins) and surgical margins (vascular/medial margins and transection margins). Overall survival was assessed for each specific resection margin.&#x0D; Results: 134 patients were included with median age 66 years. R1-resection was done in 54% of patients(n=72/134). Median survival of R0-resection group was 6.3 years, compared to 1.9 years for R1-resection group(p-value 0.001). Vascular (surgical) margins had the lowest survival rate (1.7years) compared to anatomical margins (anterior, posterior and circumferential margins) with 3.6, 2.2 and 2.1 years respectively (p-value 0.02). On multivariate analysis; lymph node involvement and vascular resection were the only factors to correlate significantly with poor survival.&#x0D; Conclusion: Whilst the new pathological protocols advised to perform rigorous margin assessment of CRM, the prognostic value of each resection margin is still unclear. This study showed variation of survival across different resection margins with inferiority towards vascular (surgical) margins. This supported the need of redefining R1-margins in the future pathological classifications according to their different prognostic impacts.

Decision-making in postoperative chemotherapy for ovarian metastasis from colorectal cancer: a retrospective single-center study

BackgroundOvarian metastases from colorectal cancer are relatively uncommon, and no consensus has been reached regarding resection of metastases or chemotherapy before and after surgery. We evaluated the clinicopathological characteristics of ovarian metastases from colorectal cancer and the impact of metastatic resection. We also performed a comparative analysis to clarify the prognostic impact of metastatic resection and the choice of chemotherapy before and after surgery.MethodsBetween 2006 and 2014, 38 patients at our institution underwent resection of ovarian metastases from colorectal cancer. Clinicopathological data were extracted from the patients’ records and evaluated with respect to the long-term outcome. For 15 patients with metachronous ovarian metastases who received chemotherapy until immediately before resection, we compared the prognosis with and without changes in the regimen after resection.ResultsThe 5-year overall survival rate was 19.9%, and the median survival duration was 27.2 months. The survival rate in the R0 resection group (n = 8) was significantly better than that in the R1/2 resection group (n = 30) (P = 0.0004). Patients without peritoneal dissemination (n = 15) or extra-ovarian metastases (n = 31) had a significantly better prognosis than those with peritoneal dissemination (n = 23) or extra-ovarian metastases (n = 7) (P = 0.040 and P = 0.0005, respectively). The progression-free survival and median survival times of patients who resumed chemotherapy after resection without a change in their preoperative regimen were 10.2 months and 26.2 months, respectively, while those among patients with a change in their regimen before resection versus after resection were 11.0 months and 18.1 months, respectively. The difference between the two groups was not statistically significant (progression-free survival time and median survival time: P = 0.52 and P = 0.48, respectively).ConclusionsPatients who underwent R0 resection of ovarian metastases clearly had a better prognosis than those who underwent R1/2 resection. Additionally, a poor prognosis was associated with the presence of peritoneal dissemination and extra-ovarian metastases. The data also suggested that resumption of chemotherapy without changing the regimen after resection could preserve the next line of chemotherapy for future treatment and improve the prognosis.

Long-term survival outcome of advanced epithelial ovarian cancer: A single institutional study.

A number of patients with advanced-stage epithelial ovarian cancer do survive beyond 5 years. The long-term follow-up data are limited, especially for the Indian setting. We evaluated the 10-year survival outcome and influencing clinicopathological factors. A retrospective analysis of advanced-stage epithelial ovarian cancer patients who underwent primary cytoreductive surgery (PCS) or interval cytoreductive surgery (ICS) from 2005 to 2008 was conducted. Survival analysis was performed with the Kaplan-Meier method, and the Cox proportional hazards model was used for prognostic clinicopathological factors analysis. Ninety-four patients with a median age of 54.5 (18-79) years were evaluated. The median follow-up period was 11.2 years. The overall survival (OS) rates at 5, 7, and 10 years were 37%, 23%, and 18%, respectively. The median OS (MOS) was 46 (95% confidence interval [CI], 36-55.8) months and progression-free survival (PFS) was 19.5 (15.3-23.6) months. Long-term survival was significantly predicted by R0 resection (complete cytoreduction with no macroscopic residual disease) and PFS >20 months while prolonged PFS was influenced by age ≤55 years and R0 resection. For the R0 resection group, patients who underwent PCS had better overall survival in comparison with ICS [72.1(25.2-119) months vs 47.4 (34.9-59.9)months] on 10 years follow-up but was not significant statistically. Patients with age ≤55 years, R0 resection, PFS >20 months have a better 10-year survival outcome. Among R0 resection, patients undergoing PCS have clinically a better outcome on 10-year follow-up.

Treatment options for giant gastrointestinal stromal tumours and related prognosis: a single-centre retrospective study.

Controversy persists about the best treatment for giant gastrointestinal stromal tumours (GISTs). This retrospective study aimed to investigate the different treatments for giant GISTs and the effect on outcomes. A total of 71 patients with GIST ≥10 cm in diameter were separated into four groups according to treatment received: emergency surgery group (n = 17), preoperative targeted (imatinib) therapy group (n = 12), palliative resection group (n = 17) and R0 resection group (n = 25). Baseline, intraoperative and post-operative findings were compared between the groups. Long-term follow-up was conducted to assess outcomes. Preoperative gastrointestinal bleeding was significantly higher (P = 0.003) and haemoglobin level was significantly lower (P < 0.05) in the emergency surgery group than in the other groups. Mean tumour diameter was significantly more in the palliative resection group than in the other groups (P = 0.023). Overall survival was significantly higher in the R0 resection group and the preoperative targeted therapy group than in the other two groups (P < 0.05). In patients with giant GISTs, the best outcomes appear to be achieved with preoperative imatinib therapy plus surgery or R0 resection followed by imatinib therapy.

O97 ADJUVANT CHEMORADIOTHERAPY IS BENEFICIAL IN MARGIN POSITIVE PATIENTS FOLLOWING NEO-ADJUVANT CHEMOTHERAPY AND SURGERY FOR LOWER OESOPHAGEAL AND GOJ ADENOCARCINOMA

Abstract Aim The aim of this study was to assess the survival benefit of adjuvant therapy in margin positive patients following neo-adjuvant chemotherapy and surgery for lower oesophageal and GOJ adenocarcinoma. Background &amp; Methods The role of adjuvant therapy in oesophago-gastric adenocarcinoma patients treated by neo-adjuvant chemotherapy is contentious. In UK practice, surgical resection margin status is often used to stratify patients into receiving adjuvant treatment. Two prospectively collected UK institutional databases were combined. Patients were classified by the adjuvant therapy received. Crude and adjusted Cox regression analyses compared overall and recurrence free survival according to the adjuvant treatment, stratified by resection margin status. Recurrence patterns were assessed as a secondary outcome. Results From a total of 616 patients, 242 had positive margins. In this R1 resection group, 112 patients (46%) received adjuvant chemoradiotherapy compared to 46 patients (19%) who received adjuvant chemotherapy and 84 patients (35%) who received no adjuvant treatment. On adjusted analysis, pathological N3 status (p&lt;0.001) and poor differentiation (p=0.024) were independently associated with overall survival. When stratified by tumour response to neo-adjuvant chemotherapy, a significant survival benefit in non-responders (Mandard Grade 4&amp;5, adjuvant chemoradiotherapy HR 0.61 95%CI 0.38-0.97; p=0.037) was observed. Additionally, adjuvant chemoradiotherapy significantly improved recurrence free survival (HR 0.59 95%CI 0.38-0.94; p=0.026) with a specific benefit for systemic recurrence (HR 0.56 95%CI 0.33-0.94; p=0.027) in both responder (Mandard Grade 1-3) and non-responder (Mandard Grade 4&amp;5) patient groups. Conclusion Adjuvant chemoradiotherapy improves overall survival, recurrence-free survival and systemic recurrence rates in R1 resection patients. This pattern is most pronounced in non-responders (Mandard 4&amp;5) to neo-adjuvant chemotherapy suggesting a change in strategy to be effective for this specific patient group.

P96 THE CURRENT ROLE OF ADJUVANT THERAPY IN PATIENTS FOLLOWING NEO-ADJUVANT CHEMOTHERAPY AND R0 RESECTION FOR LOWER OESOPHAGEAL AND GOJ ADENOCARCINOMA

Abstract Aim The aim of this study was to assess the survival benefit of adjuvant therapy in R0 resection patients following neo-adjuvant chemotherapy and surgery for lower oesophageal and GOJ adenocarcinoma. Background &amp; Methods The role of adjuvant therapy in oesophago-gastric adenocarcinoma patients treated by neo-adjuvant chemotherapy is contentious. In UK practice surgical resection margin status is often used to stratify patients into receiving adjuvant treatment. Two prospectively collected institutional databases were combined. Patients were classified by the adjuvant therapy received. Crude and adjusted Cox regression analyses compared overall and recurrence free survival according to the adjuvant treatment, stratified by resection margin status. Recurrence patterns were assessed as a secondary outcome. Results A total of 616 patients were included (373 R0, 243 R1). In hospital mortality following surgery was 1% and these patients were excluded from analysis (n=7). In the R0 resection group 220 patients (59%) had no adjuvant treatment and 137 patients (37%) had adjuvant chemotherapy. On adjusted analysis pathological N status (p&lt;0.0001), poor differentiation (p=0.005) and poor response to neo-adjuvant chemotherapy (p=0.001) were independently associated with poor survival. The benefit of adjuvant chemotherapy did not reach independent significance (HR 0.65 95% CI 0.40-1.06; p=0.087) compared to no treatment. However, it was observed that responders to neo-adjuvant chemotherapy (Mandard 1-3) were more likely to demonstrate a survival benefit from adjuvant chemotherapy (HR 0.42 95%CI 0.15-1.11; p=0.081) than those who are deemed to be non-responders (Mandard 4&amp;5, HR 0.71 95%CI 0.39-1.32; p= 0.280). Conclusion Adjuvant chemotherapy may have a survival benefit in R0 resection patients following surgery, but this is likely to be limited to patients exhibiting a good response to neo-adjuvant chemotherapy.

Importance of Radiotherapy Timing and Resection Margin Status for Postoperative Radiotherapy in Extremity STS

It is well known that adjuvant radiotherapy (RT) improves local control in extremity STS (STS) patients because it is difficult to obtain adequate surgical margin while conserving function. However, the treatment options are still debatable due to some practical problem such as lack of multi-disciplinary approach. The aim of this study was to analyze whether the treatment outcome of extremity STS differs by resection margin status and RT timing who received conserving surgery and postoperative RT. A total of 260 extremity STS patients who treated with conserving surgery and postoperative RT between January 1981 and June 2017 were included in this study. Patients who received amputation or palliative RT were excluded. We classified the surgical resection margin status into three groups using the R classification; R0, R1, R2 margin. We also categorized the timing of RT into two; Immediate and delayed RT. Immediate RT was defined as planned RT after the first conserving operation of STS. We defined delayed RT as RT performed after re-operations for several times due to local recurrence. The primary end point was local control (LC). Progression free survival (PFS) was also evaluated. In addition, propensity score matching was performed to balance the characteristics between the two groups; immediate RT group, delayed RT group. The LC rate and PFS were evaluated using Kaplan-Meier curves, and log-rank test for statistical significance. P values less than 0.05 were considered statistically significant. The LC and DFS were significantly worse for patients with R2 resected tumor comparing with R0 or R1 resected group (5-year LC R0: 84.8%, R1: 80.3%, R2: 62.0%, p < 0.001; 5-year DFS R0: 68.9%, R1: 60.8%, R2: 43.1%, p = 0.001). In regard to timing of RT, the adjuvant RT group (81.9%) showed better LC than salvage RT group (66.8%, p = 0.002). Through the subgroup analysis, the R1 resection group showed the biggest difference of LC between adjuvant RT group (85.6%) and salvage RT group (49.1%, p < 0.001). Among the patients received adjuvant RT, the LC of R1 group (85.6%) was comparable to R0 group (89.5%, p = 0.738). Concordant with LC results, adjuvant RT (64.8%) showed better DFS than salvage RT (44.7%, p= 0.007) The difference of 5-year DFS was significant between adjuvant RT (65.2%) and salvage RT (20.7%) for R1 resected group (p < 0.001) and among adjuvant RT group, R0 (66.2%) and R1 (65.2%) group showed comparable results (p = 0.844). The resection margin status was well correlated with LC and DFS. For timing of RT, the adjuvant RT showed better LC and DFS than salvage RT group. Following these results, R0 resection group and R1 resection group showed comparable LC and DFS when adjuvant was performed.

Tracheo-bronchial adenoid cystic carcinoma: A retrospective study.

Adenoid cystic carcinoma (ACC) of the trachea and bronchus is rare, representing 1% of all respiratory tract cancers. We presented our experiences in treating tracheal-bronchial ACC and the results of long-term surveillance. We conducted a retrospective study of treating tracheo-bronchial ACC. From 2009 to 2014, 42 patients presented to our department. All of them received surgical resection andadjunctive therapy. R0 resections were achieved in 33 patients, whereas 15 patients whose lesions spread outside the tracheo-bronchial lumens. Nine patients had R1 resections followed by radiation and chemotherapy. The 5 year survival rate of R1 resection group showed no difference compared to the R0 resection group, but the 5 year disease-free survival rate showed difference in extra-lumenal invasion (ELI) and non-ELI group (P=0.0357<0.05), although no difference was seen in the overall survival rate in these two groups. ACC of the trachea and bronchus is a rare and low-to-moderate grademalignant tumor. When the R0 resection is over risky or may cause mortal complication, the R1 resection with adjunctive therapy is acceptable for patients to obtain a promising prognosis, whereas pathological ELI is an adverse prognostic indicator.

The effect of adjuvant chemotherapy in resectable cholangiocarcinoma: A meta-analysis and systematic review

BackgroundThe benefit of adjuvant chemotherapy for resectable cholangiocarcinoma remains unclear due to the lack of randomized control studies. This study aimed to investigate the possible benefit of postoperative adjuvant chemotherapy for resectable cholangiocarcinoma. Data sourcesRelevant research articles published before 1st March 2018 in PubMed, Embase and the Cochrane library databases were retrieved. Published data were extracted and analyzed by RevMan 5.3, and the results were presented as hazard ratios (HRs) [95% confidence intervals (CI)] and forest plots. ResultsOne prospective and eighteen retrospective studies were included, with a total number of 11,458 patients, 4696 of whom received postoperative chemotherapy. There was a significant improvement of the overall survival (OS) for patients who underwent operation + adjuvant chemotherapy compared to those who underwent operation alone (HR = 0.61; P < 0.001). Subgroup analyses show that the postoperative chemotherapy group compared with operation alone group are indicated as follows: hilar cholangiocarcinoma group (HR = 0.60; P < 0.001), intrahepatic cholangiocarcinoma group (HR = 0.60; P < 0.001), R1 resection group (HR = 0.71; P = 0.04), LN-positive diagnosis group (HR = 0.58; P < 0.001), gemcitabine-based chemotherapy group (HR = 0.42; P < 0.001), distal cholangiocarcinoma group (HR = 0.48; P = 0.17), R0 resection group (HR = 0.69; P = 0.43), and 5-flurouracil-based chemotherapy group (HR = 0.90; P = 0.66), respectively. ConclusionsPostoperative adjuvant chemotherapy can improve the OS in intrahepatic and hilar cholangiocarcinoma patients. However, distal cholangiocarcinoma patients gain no benefit from postoperative adjuvant chemotherapy. Prospective randomized trials are warranted in order to define the standard chemotherapy regimen.

The Strategy of Treatment for Mid to Distal Cholangiocarcinoma after Surgical Resection

The overall survival (OS) rate of extrahepatic cholangiocarcinoma (ECC) remains much lower than that for other gastrointestinal malignancies. A variety of factors have been used to predict prognosis after surgical resection for ECC, but no consensus has been reached. Therefore, this study sought to identify useful prognostic factors for patients with ECC. In our institution, within the study period, 76 patients received surgical resection for mid to distal cholangiocarcinoma. Clinicopathological data were retrospectively collected, along with survival and prognosis. In multivariate analysis for OS, ductal margin status (P = 0.008) and pT category (P < 0.02) presented independent predictors of survival. In the R0 resection group, N stage and adjuvant chemotherapy presented independent predictors of recurrence in the multivariate model. The three- and five-year survival rates were significantly better in patients with negative ductal margins (77.% at three years and 63.6% at five years) than in those with positive ductal margins (33.3% at three years and 25.0% at five years) (P < 0.05). Survival rates were similar between cases of R0 resection without gemcitabine-based chemotherapy and R1 resection with gemcitabine-based chemotherapy (P = 0.6193, Log-rank test). However, survival rates between R0 resection with gemcitabine-based chemotherapy and R1 resection with gemcitabine-based chemotherapy were significantly different (P = 0.0086, Log-rank test). For good prognosis, radical resection to ensure adequate margin may be recommended for middle common bile duct cancer. In addition, regardless of margin negativity, gemcitabine-based chemotherapy is recommended for prolongation of relapse-free time and OS time.

Optimal combination of treatment modality to increase survival in patients with anaplastic thyroid carcinoma: A STROBE compliant retrospective study.

There is little consensus on the optimal treatment approach for newly diagnosed patients. The present study aims to provide additional evidence by evaluating a series of patients diagnosed with anaplastic thyroid carcinoma (ATC) and analyzing factors related to increased survival. This was a retrospective cohort report structured according to the Strengthening the Reporting of Observational studies in Epidemiology (STROBE) guideline. Demographics, chief complaint, history of prior thyroid cancer, stage at presentation, management modalities (surgery, chemotherapy, radiotherapy, or observation), completeness or resection, and survival period since initial diagnosis were reviewed for patients with documentation of histologic ATC diagnosis between 2003 and 2016. The median survival period for 34 patients (11 males, 23 females) was 93.5 days. Patients aged 70 or younger (111 days) tended to survive longer than those older 70 (88 days) (P = .081). Observation, surgery only, radiotherapy only, and chemo-radiotherapy after surgery group showed median survival of 88 days, 49 days (range 14–528), 61.5 days, and 225 days, respectively. There was also no significant difference in survival between the 10 (29.4%) stage IVb (225 days) and 23 (67.7%) IVc (88 days) patients (P = .242). The median survival of the R1 resection group was 514 days while that of the R2 group was 102 days (P = .338). There were no significant difference between patients with the de novo ATC (112 days) and patients with papillary thyroid carcinoma origin ATC (99 days) (P = .297). Results from our series of 34 patients with ATC show that more intense combination of surgery and chemo-radiotherapy tends to secure a longer survival period. Therefore we recommend a multi-modality approach after a comprehensive consultation with the patient.

Adjuvant therapy for margin positive pancreatic cancer.

390 Background: Pancreatic cancer continues to have a dismal prognosis despite improvements in surgical care. Approximately 26% of patients are deemed resectable, and at the time of operation, 28% will have R1 resections. Adjuvant chemotherapy (AC) or chemoradiation (CRT) is recommended, however the magnitude of benefit is unclear. We sought to examine the impact these therapies on R1 resected pancreatic cancer. Methods: Utilizing the National Cancer Database we identified patients who underwent pancreatic resection for adenocarcinoma. Patients were stratified by resection status and adjuvant therapy. Baseline comparisons of patient characteristics were made using Mann-Whitney U, Kruskal Wallis and Pearson’s Chi-square test as appropriate. Survival analyses were performed using the Kaplan-Meier method. Multivariable cox proportional models(MVA) were developed to identify predictors of survival. All statistical tests were two-sided and α &lt;0.05 was considered significant. Results: We identified 28,440 patients: 22,005 (77.4%) underwent R0 resections and 6,435 (22.4%) underwent R1 resections with a median age of 67.5 years (18-90) and median tumor size of 3.1 cm (2.4-4.2). Patients with tumor size &gt;2cm were more likely to undergo R1 resections, p&lt;0.001. Within the R1 resection group, AC was administered in 1,802 (19.4%), CRT 2,153 (28.5%), and no adjuvant therapy (NA) 2,480 (21.4%). Adjuvant therapy improved survival in all patients with median and 5-year survival of: AC (21.7 months, 17.45%), CRT (23.3 months, 20.9%) vs NA (19.5 months, 19.1%), p&lt;0.001. In the R1 resection cohort survival was also improved with adjuvant therapy with CRT demonstrating the most significant improvement: AC (15.9 months, 6.5%), CRT (18.7 months. 11.2%) vs NA (12.5 months, 8.7%), p&lt;0.001. Additionally CRT but not AC improved survival in the R1 node negative, p&lt;0.004, and node positive, p&lt;0.001. AC benefited survival in R1 node positive patients, p&lt;0.001. MVA revealed age, tumor grade, tumor size &gt;2cm, T-stage, N-stage, AC, and CRT were predictive of survival. Conclusions: Patients with pancreatic cancer who undergo R1 resection have significant improvement in survival when treated with adjuvant CRT and AC. However, benefits were greater in those receiving adjuvant CRT.

P3.16-016 Prognosis of Patients with Remnant Tumor at Bronchial Stump After Pulmonary Resection for NSCLC: Based on Case Series Study

Current guidelines recommend adjuvant therapy for positive margins after surgical resection. However, there is no strong evidence for those adjuvant therapies. In this study, we analyzed series of patients with microscopically tumor-positive bronchial stump (R1) and compared it with patients with complete R0 resection. From 2011 to 2015, 172 patients underwent surgical treatment for NSCLC at out center. Excluding three patients with pleural seeding and residual tumors at parenchymal resection margin, 10 patients were bronchial R1 resection. We performed a retrospective analysis of patients’ data during follow-up (mean 36.6 months). All patients with R1 disease received adjuvant therapies. Mode of adjuvant therapy was not related to recurrence (P=0.683) within R1 group. Kaplan-Meier analysis showed that recurrence rate in R1 group was higher compared to R0 resection group (P=0.001) when no stratification for staging was done. However, overall survival was not different between two groups (P=0.087). In this study, R1 resection group was revealed as a risk factor for tumor recurrence while it did not significantly affect overall survival. The type of adjuvant therapy had no relation to the recurrence of NSCLC. But further investigation with large cohort is necessary to find out the exact effect of adjuvant therapy and stage.