Neoadjuvant Chemotherapy With CAPOX Versus Chemoradiation for Locally Advanced Rectal Cancer With Uninvolved Mesorectal Fascia (CONVERT): Initial Results of a Phase III Trial.

OBJECTIVE: To compare neoadjuvant chemotherapy (nCT) with CAPOX alone versus neoadjuvant chemoradiotherapy (nCRT) with capecitabine in locally advanced rectal cancer (LARC) with uninvolved mesorectal fascia (MRF). BACKGROUND DATA: nCRT is associated with higher surgical complications, worse long-term functional outcomes, and questionable survival benefits. Comparatively, nCT alone seems a promising alternative treatment in lower-risk LARC patients with uninvolved MRF. METHODS: Patients between June 2014 and October 2020 with LARC within 12 cm from the anal verge and uninvolved MRF were randomly assigned to nCT group with 4 cycles of CAPOX (Oxaliplatin 130 mg/m2 IV day 1 and Capecitabine 1000 mg/m2 twice daily for 14 d. Repeat every 3 wk) or nCRT group with Capecitabine 825 mg/m² twice daily administered orally and concurrently with radiation therapy (50 Gy/25 fractions) for 5 days per week. The primary end point is local-regional recurrence-free survival. Here we reported the results of secondary end points: histopathologic response, surgical events, and toxicity. RESULTS: Of the 663 initially enrolled patients, 589 received the allocated treatment (nCT, n=300; nCRT, n=289). Pathologic complete response rate was 11.0% (95% CI, 7.8-15.3%) in the nCT arm and 13.8% (95% CI, 10.1-18.5%) in the nCRT arm ( P =0.33). The downstaging (ypStage 0 to 1) rate was 40.8% (95% CI, 35.1-46.7%) in the nCT arm and 45.6% (95% CI, 39.7-51.7%) in the nCRT arm ( P =0.27). nCT was associated with lower perioperative distant metastases rate (0.7% vs. 3.1%, P =0.03) and preventive ileostomy rate (52.2% vs. 63.6%, P =0.008) compared with nCRT. Four patients in the nCT arm received salvage nCRT because of local disease progression after nCT. Two patients in the nCT arm and 5 in the nCRT arm achieved complete clinical response and were treated with a nonsurgical approach. Similar results were observed in subgroup analysis. CONCLUSIONS: nCT achieved similar pCR and downstaging rates with lower incidence of perioperative distant metastasis and preventive ileostomy compared with nCRT. CAPOX could be an effective alternative to neoadjuvant therapy in LARC with uninvolved MRF. Long-term follow-up is needed to confirm these results.

Short-term Outcomes of Laparoscopy-Assisted vs Open Surgery for Patients With Low Rectal Cancer: The LASRE Randomized Clinical Trial.

Importance: The efficacy of laparoscopic vs open surgery for patients with low rectal cancer has not been established. Objective: To compare the short-term efficacy of laparoscopic surgery vs open surgery for treatment of low rectal cancer. Design, Setting, and Participants: This multicenter, noninferiority randomized clinical trial was conducted in 22 tertiary hospitals across China. Patients scheduled for curative-intent resection of low rectal cancer were randomized at a 2:1 ratio to undergo laparoscopic or open surgery. Between November 2013 and June 2018, 1070 patients were randomized to laparoscopic (n = 712) or open (n = 358) surgery. The planned follow-up was 5 years. Data analysis was performed from April 2021 to March 2022. Interventions: Eligible patients were randomized to receive either laparoscopic or open surgery. Main Outcomes and Measures: The short-term outcomes included pathologic outcomes, surgical outcomes, postoperative recovery, and 30-day postoperative complications and mortality. Results: A total of 1039 patients (685 in laparoscopic and 354 in open surgery) were included in the modified intention-to-treat analysis (median [range] age, 57 [20-75] years; 620 men [59.7%]; clinical TNM stage II/III disease in 659 patients). The rate of complete mesorectal excision was 85.3% (521 of 685) in the laparoscopic group vs 85.8% (266 of 354) in the open group (difference, -0.5%; 95% CI, -5.1% to 4.5%; P = .78). The rate of negative circumferential and distal resection margins was 98.2% (673 of 685) vs 99.7% (353 of 354) (difference, -1.5%; 95% CI, -2.8% to 0.0%; P = .09) and 99.4% (681 of 685) vs 100% (354 of 354) (difference, -0.6%; 95% CI, -1.5% to 0.5%; P = .36), respectively. The median number of retrieved lymph nodes was 13.0 vs 12.0 (difference, 1.0; 95% CI, 0.1-1.9; P = .39). The laparoscopic group had a higher rate of sphincter preservation (491 of 685 [71.7%] vs 230 of 354 [65.0%]; difference, 6.7%; 95% CI, 0.8%-12.8%; P = .03) and shorter duration of hospitalization (8.0 vs 9.0 days; difference, -1.0; 95% CI, -1.7 to -0.3; P = .008). There was no significant difference in postoperative complications rate between the 2 groups (89 of 685 [13.0%] vs 61 of 354 [17.2%]; difference, -4.2%; 95% CI, -9.1% to -0.3%; P = .07). No patient died within 30 days. Conclusions and Relevance: In this randomized clinical trial of patients with low rectal cancer, laparoscopic surgery performed by experienced surgeons was shown to provide pathologic outcomes comparable to open surgery, with a higher sphincter preservation rate and favorable postoperative recovery. Trial Registration: ClinicalTrials.gov Identifier: NCT01899547.

Effects of CO2 pneumoperitoneum on the expression of thymidine kinase 1 and Ki67 in colorectal carcinoma cells.

BACKGROUND: To investigate thymidine kinase 1(TK-1) and Ki67 expression levels of human colorectal carcinoma cells line SW480 after exposure to a simulated laparoscopic carbon dioxide (CO2) pneumoperitoneum environment at different pressures and lengths of exposure time. METHODS: The effects of the simulated laparoscopic CO2 pneumoperitoneum environment at different CO2 pressures (6, 9, 12, and 15 mmHg) and exposure times (2 and 4 h) on TK-1 and Ki67 of SW480 cells were assessed by flow cytometry and reverse transcription (RT-PCR). Cells cultured in a standard environment were used as the control group (at 37 °C, 5% CO2). RESULTS: In this study, TK-1 and Ki67 in SW480 cells tended to decrease with the increase of CO2 pressure and exposure time. Significantly lower expression levels were observed at 0 and 24 h of culture after exposure to both at 12 and 15 mmHg, as compared with the control group at 6 and 9 mmHg (p < 0.05). The expression of TK-1 and Ki67 levels increased up to a plateau of the control group after 48 and 72 h (p > 0.05). With the CO2 pneumoperitoneum exposure time prolonging, the expression of TK-1 and Ki67 levels in 12 or 15 mmHg was lower than in 2 h (p < 0.05). In the same exposure time, the transcription level of TK-1 and Ki67 decreased significantly in 12 and 15 mmHg CO2 pneumoperitoneum groups (p < 0.05) and returned to the basal level of control group after being cultivated for 48 h (p > 0.05). In the same pressure, the difference of TK-1 mRNA between the groups of 2 and 4 h was also significant. CONCLUSION: The expression levels of TK-1 and Ki67 were suppressed temporarily after the continuous CO2 insufflation in higher pressure (at 12 and 15 mmHg). The higher the pressure of CO2 insufflation, the more the inhibiting effects of TK-1 and Ki67 will be. The longer the time of CO2 insufflation, the more significantly their expression decreased.

Effect of CO2 pneumoperitoneum on the expression of the chemokine receptors CXCR4 and CCR7 in colorectal carcinoma cells in vitro.

BACKGROUND: The ability of pneumoperitoneum in laparoscopic surgery to promote proliferation and metastasis of colorectal cancer has become a focus of research in the field of minimally invasive surgery. The aim of this research was to investigate the effect of CO2 pneumoperitoneum under different pressures and exposed times on the expression of chemokine receptors in colorectal carcinoma cells. METHODS: We constructed an in vitro pneumoperitoneum model. SW480 colon carcinoma cells were exposed to CO2 pneumoperitoneum under different pressures (6, 9, 12, and 15 mmHg) for 1, 2, and 4 hours. These cells were then cultivated under the same conditions as normal SW480 colon carcinoma cells without CO2 pneumoperitoneum (control group), treated at 37°C, and 5% CO2. The expression of the chemokine receptors CXC receptor 4 (CXCR4) and chemokine C receptor 7 (CCR7) was detected by immunocytochemistry and reverse transcriptase polymerase chain reaction after being cultivated for 0, 24, 48, and 72 hours. RESULTS: Immunocytochemistry showed that CXCR4 expression in SW480 cells was significantly decreased in the 6, 9, 12, and 15 mmHg CO2 pneumoperitoneum-treated groups for the same exposure times compared with controls (P < 0.05). CCR7 expression in SW480 cells was significantly decreased in the 12 and 15 mmHg CO2 pneumoperitoneum-treated groups compared with controls (P < 0.05). CXCR4 and CCR7 expression increased up to the level of the control group after 24 and 48 hours (P > 0.05). If the CO2 pneumoperitoneum pressure increased, CXCR4 and CCR7 expression decreased at all exposure times. If the CO2 pneumoperitoneum exposure time prolonged, there were no significant differences in CXCR4 and CCR7 expression under the same pressure. Under all exposure times, CXCR4 and CCR7 mRNA expression was significantly decreased in the 6, 9, 12, and 15 mmHg CO2 pneumoperitoneum-treated groups (P < 0.05) compared with controls, and it increased up to the level of controls after being cultivated for 48 hours (P > 0.05). If the CO2 pneumoperitoneum pressure increased (with all exposure times) and exposure time prolonged (under the same pressure), there were no significant differences in CXCR4 and CCR7 expression. CONCLUSIONS: CXCR4 and CCR7 expression is temporarily affected after continuous CO2 pneumoperitoneum treatment. The high pressure of CO2 pneumoperitoneum plays an important role in suppressing the expression of these chemokine receptors. Different lengths of time of exposure to a CO2 pneumoperitoneum-like environment do not change CXCR4 and CCR7 expression.

Effects of γ-synuclein on the tumorigenicity and metastasis of colon cancer SW1116 cells in vitro and in vivo.

Recent evidence suggests the involvement of γ-synuclein in tumorigenesis and tumor progression. The present study was designed to further clarify the effects of γ-synuclein on the biological features of colon cancer cells in vitro and in vivo. We constructed the eukaryotic expression vector and siRNA vector and selected stable transfectants to respectively upregulate and downregulate γ-synuclein expression in SW1116 cells. we found that silencing of γ-synuclein significantly attenuated SW1116 cell growth and colony formation in vitro (P<0.05), and overexpression of γ-synuclein moderately enhanced cell growth and colony formation, but not significantly when compared with the parental SW1116 cells and empty vector-transfected cells (P>0.05). Meanwhile, overexpression of γ-synuclein significantly facilitated SW1116 cell migration, invasion and adhesion to human liver sinusoidal endothelial cells (HLSECs) in vitro (P<0.05), and the effects were less attenuated by γ-synuclein knockdown (P>0.05). Furthermore, γ-synuclein promoted these malignant phenotypes in a γ-synuclein expression quantity-dependent manner not only in vitro but also in the in vivo expression. stable cells were injected subcutaneously into the right flank, and injected intrasplenically in nude mice. γ-synuclein knockdown suppressed the tumorigenicity of SW1116 cells in mice, which presented significantly smaller tumor masses on day 6 over a 30-day period, compared with empty vector cells (P<0.05). Meanwhile, overexpression of γ-synuclein led to a profound augmentation of liver metastasis in nude mice, not only in macroscopic appearance but also in the size and weight of livers (P<0.05). These results provide strong evidence that suggests γ-synuclein plays a positive role in the progression of colorectal cancer.

[Clinical characteristics, diagnosis and treatment of hepatoid adenocarcinoma of the stomach].

OBJECTIVE: To investigate the clinical characteristics,diagnosis and treatment of hepatoid adenocarcinoma of the stomach. METHODS: Clinical data of 13 hepatoid adenocarcinomas of the stomach, collected from 201 cases of gastric cancer, were analyzed retrospectively. RESULTS: Of the 201 gastric carcinomas, there were 13 AFP-producing adenocarcinomas of the stomach, the positive rate was 6.5%. Morphologically, the tumor cells formed glandular, medullary and linear structures. Of the 13 hepatoid adenocarcinomas of the stomach, 10 cases were in gastric antrum and 10 cases were poorly differentiated. The metastasis rates of liver and lymph node in hepatoid adenocarcinoma of stomach were higher than those in non-hepatoid adenocarcinoma of stomach. The treatment of hepatoid adenocarcinoma of stomach depended mainly on radical resection, and adjuvant chemotherapy was needed.The prognosis of hepatoid adenocarcinoma of stomach was poor. CONCLUSION: Hepatoid adenocarcinoma of the stomach has its own special tumor biological behavior and poor prognosis. Special attention should be paid to this disease.