The association between surgical site infection and postoperative colorectal cancer recurrence and the effect of laparoscopic surgery on prognosis.

PURPOSE: Studies have shown that surgical site infection (SSI) incidence is lower in patients undergoing laparoscopic surgery. Therefore, we reported the SSI countermeasures adopted by our institution and aimed to evaluate the association between SSI occurrence and postoperative colorectal cancer recurrence and the usefulness of laparoscopic surgery for prognosis. METHODS: Among the patients with colorectal cancer who underwent radical surgery at our hospital between January 2015 and December 2017, 197 with stage I-III cancer without distant metastases were included. We retrospectively analyzed patients' electronic medical records and classified them into the non-SSI (without SSI, n = 159) and SSI (with SSI, n = 38) groups. We calculated and compared the 5-year relapse-free survival (RFS) and overall survival (OS) rates. Additionally, we assessed the relationship between prognosis in the non-SSI, incisional SSI, and organ/space SSI groups and the usefulness of laparoscopic surgery. RESULTS: The 5-year RFS and OS were 80.5% versus 63.2% (P = 0.024; hazard ratio [HR], 2.065; 95% confidence interval [CI], 1.099-3.883) and 88.7% versus 84.2% (P = 0.443; HR, 1.436; 95% CI, 0.570-3.617), respectively. The SSI group had a significantly worse 5-year RFS prognosis. Regarding the relationship with laparoscopic surgery, the SSI incidence was 45.0% (9/20 cases) and 16.4% (29/177 cases) with laparotomy and laparoscopic surgery, respectively, indicating a significantly reduced SSI occurrence with laparoscopic surgery (P = 0.005). CONCLUSION: Patients with SSI were at high risk for colorectal cancer recurrence, and laparoscopic surgery may be useful for reducing SSI.

A single-center retrospective analysis of the efficacy and safety of a modified regimen of irinotecan plus S-1 (IRIS) with molecular targeting agents as second-line chemotherapy in Japanese patients with recurrent or nonresectable colorectal cancer.

Background: As the second-line chemotherapy for stage IV recurrent or nonresectable colorectal cancer, our hospital started a modified treatment regimen comprising of irinotecan plus S-1 (IRIS) [tegafur/gimeracil/oteracil (S-1)] plus molecular targeting agents (MTAs), i.e., an epidermal growth factor receptor (EGFR) inhibitor such as panitumumab (P-mab) or cetuximab (C-mab) or vascular endothelial growth factor (VEGF) inhibitor such as bevacizumab (B-mab) since October 2012. The purpose of this study is to evaluate the efficacy and safety of this modified regimen. Methods: This retrospective study included 41 patients with advanced recurrent colorectal cancer at our hospital whom at least 3 courses of chemotherapy were conducted from January 2015 to December 2021. Based on the location of the primary tumor, patients were classified into two group (right-sided group, proximal to the splenic curve, and left-sided, distal to the splenic curve). We assessed archived data on RAS and BRAF status and UGT1A1 polymorphisms and use of the VEGF inhibitor bevacizumab (B-mab) and the EGFR inhibitors panitumumab (P-mab) and cetuximab (C-mab). In addition, progression-free survival rate (36M-PFS) and the overall survival rate (36M-OS) were calculated. Furthermore, the respective median survival time (MST), the median number of treatment courses; the objective response rate (ORR) and clinical benefit rate (CBR) and the incidence of adverse events (AEs) were assessed as well. Results: There were 11 patients (26.8%) in the right-sided group, and 30 patients (73.2%) in the left-sided group. There were 19 patients with RAS wild type (46.3%) (1 in the right sided group and 18 in the left sided group). P-mab was used for 16 of these patients (84.2%), C-mab for 2 (10.5%), and B-mab for 1 (5.3%); the remaining 22 patients (53.7%). Ten patients in the right group and 12 patients in the left group were a mutated type and received B-mab. BRAF testing was performed in 17 patients (41.5%); as more than 50% of patients (58.5%) were included before the assay's introduction. Five patients in the right-sided group and 12 patients in the left-sided group had wild type. There was no mutated type. UGT1A1 polymorphism was tested in 16/41 patients: Eight were wild type (8/41 patients, 19.5%) and 8, mutated type. Regarding the *6/*28 double heterozygous type, there was only 1 patient in the right-sided group and the remaining 7 patients were in the left-sided group. The total number of chemotherapy courses was 299, and the median number, 6.0 (range, 3-20). PFS, OS, and MST were as follows: 36M-PFS (total/Rt/Lt), 6.2%/0.0%/8.5% (MST; 7.6/6.3/8.9 months); and 36M-OS (total/Rt/Lt), 32.1%/0.0%/44.0% (MST; 22.1/18.8/28.6 months). The ORR and CBR were 24.4% and 75.6%, respectively. The majority of AEs were grades 1 or 2 and were improved with conservative treatment. Grade 3 leukopenia was observed in 2 cases (4.9%), neutropenia in 4 cases (9.8%), and malaise/nausea/diarrhea/perforation in 1 case each (2.4%). Grade 3 leukopenia (2 patients) and neutropenia (3 patients) were more commonly observed in the left-sided group. Diarrhea and perforation were also common in the left-sided group. Conclusions: This second-line modified IRIS regimen with MTAs is safe and effective and results in good PFS and OS.

Scatter patterns in lymph node metastases as a novel prognostic indicator in patients with stage III/N2 colorectal cancer.

To classify patients with stage III/N2 colorectal cancer into high- and low-risk groups for recurrence, the present study compared clinicopathological features by immunohistochemical staining. The single-center analysis included 53/668 patients (7.9%) with stage III/N2 colorectal cancer who underwent radical resection between January 2006 and December 2014. The present study examined cancer cell distribution in metastatic lymph nodes and classified patients into a group with circumferential localization patterns like a cystic mass (CLP) and a group with scatter patterns like fireworks (SPF). Subsequently, 5-year relapse-free survival (5Y-RFS) and 5-year overall survival (5Y-OS) rates were compared and the histological type (differentiation degree) of the primary adenocarcinoma was included. The CLP group included 16 patients (30.2%) and the SPF group included 37 patients (69.8%). The 5Y-RFS rates in these groups were 75.0 vs. 37.8%, respectively (P=0.021), and the 5Y-OS rates were 81.3 vs. 48.6% (P=0.033). Patient clinicopathological characteristics exhibited no significant differences between groups. The adenocarcinoma was well differentiated in 14 patients (Well; 26.4%) and moderately (Mod; n=37) or poorly (Por; n=2) differentiated in 39 patients (Mod+Por; 73.6%). Patients were further classified into four groups: Well/CLP (n=6), Well/SPF (n=8), Mod+Por/CLP (n=10) and Mod+Por/SPF (n=29). For Well/CLP vs. Well/SPF, the 5Y-RFS rates were 66.7 vs. 25.0%, respectively (P=0.293), and for Mod+Por/CLP vs. Mod+Por/SPF (80.0 vs. 41.4%; P=0.052), the respective values for 5Y-OS were 66.7 vs. 50.0% (P=0.552) and 90.0 vs. 48.3% (P=0.059). Based on the aforementioned results, the CLP group was considered a low-risk group for recurrence with a relatively good prognosis; however, the SPF group was considered a high-risk group for recurrence with a poor prognosis, suggesting a need for more potent multi-combination chemotherapy in these patients from the early postoperative period.

Pelvic local recurrence as first relapse predicts prognosis for clinical stage II/III lower rectal cancer: A clinicopathological investigation.

The present study investigated the association between the mode of tumor recurrence and prognosis in 123 patients with clinical stage II/III rectal cancer. In the past 10 years, patients received systemic chemotherapy following radical (R0, with no macroscopic residual tumor lesions) resection using total or tumor-specific mesorectal excision. Patients with rectosigmoid cancer and T4 + chemoradiation therapy were excluded from the present study. The 5-year relapse-free survival rate (5Y-RFS), 5-year overall survival rate (5Y-OS), and associations between early post-operative complications, recurrence mode and prognosis, as well as the 5Y-OS of patients with relapsed cancer, were calculated. The overall 5Y-RFS and 5Y-OS were 71.4 and 83.5%, respectively, and the overall recurrence rate was 22.8% (28/123 patients). Among relapses, remote metastases were observed in 17/123 patients (13.8%): The lung in 8 patients (6.5%), the liver in 5 patients (4.1%) and elsewhere in 4 patients (3.3%). A total of 11 patients (8.9%) had pelvic local recurrence as the first relapse, which was located anterior to the sacrum in 7 patients (5.7%), at the anastomosis site in 2 patients (1.6%), and in the inner pelvis in 2 patients (1.6%). Among relapsed patients, the 5Y-OS was 69.3% in those with distant metastases and 27.3% in those with local relapse (P=0.02; no significant differences in patient demographics). The results indicated that advanced rectal cancer and control of pelvic local recurrence are manageable by R0 resection and postoperative chemotherapy. However, for patients whose initial relapse was pelvic local recurrence, the relapsed tumor initiated a new metastatic cascade to organs, such as the lung and liver, and affected prognosis.

Free­floating cancer cells in lymph node sinuses of hilar lymph node­positive patients with non­small cell lung cancer.

Previous studies demonstrated that free­floating cancer cells (FFCCs) in the lymph node sinuses were of prognostic significance for colorectal and gastric cancer. The present study investigated the clinical significance of detecting FFCCs using Fast Red staining for cytokeratin in stage I/II non­small cell lung cancer (NSCLC) patients and hilar lymph node positive NSCLC patients who underwent curative resection. Between 2002 and 2011, a total of 164 patients (including 22 hilar lymph node positive patients) were investigated. Resected lymph nodes were stained for cytokeratin using an anti­cytokeratin antibody. In order to achieve a clear distinction from coal dust, an anti­cytokeratin antibody was labeled with a secondary antibody conjugated with alkaline phosphatase, which was detected by a reaction with Fast Red/naphthol that produced a red color. Patients were considered to be positive for FFCCs (FFCCs+) if one or more than one free­floating cytokeratin­positive cell was detected in the lymph node sinuses, which could not be detected by hematoxylin and eosin staining. Among all 164 patients, a significant difference was observed in 5­year relapse­free survival (5Y­RFS) rates, with 76.9 and 33.3% being achieved by FFCCs­ and FFCCs+ patients, respectively (P<0.001). Similarly, the 5­year overall survival (5Y­OS) rate was significantly lower in FFCCs+ patients, with 86.6% being achieved by FFCCs­ and 65.8% by FFCCs+ patients, respectively (P=0.014). Among 22 hilar lymph node­positive patients, a significant difference was also observed in 5Y­RFS, with 53.8 and 0.0% being achieved by FFCCs­ and FFCCs+ patients, respectively (P=0.006). The 5Y­OS tended to be lower in FFCCs+ patients, with 69.2 and 53.3% being achieved by FFCCs­ and FFCCs+ patients, respectively (P=0.463). The findings of the present study suggested the presence of FFCCs in stage I/II NSCLC patients was associated with a poor prognosis. In addition, FFCCs in hilar lymph node­positive patients may potential be a useful marker in foreseeing the recurrence of cancer.

Occult neoplastic cells in lymph node sinuses and recurrence/metastasis of stage II/III gastric cancer.

In the present study, we investigated the correlation between the presence of occult neoplastic cells (ONCs) in lymph node sinuses and recurrence/metastasis of stage II/III gastric cancer in 164 patients who underwent radical curative resection. We calculated the five-year relapse-free survival rate (5Y-RFS) and five-year overall survival rate (5Y-OS) of the ONC(+) and ONC(-) groups. The 5Y-RFS was 71.4% in the ONC(-) group and 47.5% in the ONC(+) group (P=0.003). The 5Y-OS was 68.8 and 48.4%, respectively (P=0.008). ONCs were found in 34.8% of stage II patients and were also detected in 66.7% of stage III patients. For distinguishing between the recurrence and non-recurrence groups, the sensitivity of ONC(+) was 64.5% (40/62; P=0.003), the positive predictive value (PPV) was 49.4% (40/81), the specificity was 59.8% (61/102) and the negative predictive value (NPV) was 73.5% (61/83). This high sensitivity indicates that ONC positivity may be a significant indicator for high-risk patients in the early postoperative period, and a lack of ONCs may be a useful indicator for identifying low-risk patients, as patients without ONCs had a high NPV.

Stage II/III cancer of the rectosigmoid junction: an independent tumor type?

The 5-year relapse-free survival rate (5Y-RFS) and 5-year overall survival rate (5Y-OS) were investigated in 766 patients with stage II/III colorectal cancer (CRC). The Stage II group included 283 patients with colon cancer (CC), 40 patients with rectosigmoid junction cancer (RSC), and 74 patients with rectal cancer (RC), while the Stage III group comprised 226 patients with CC, 52 patients with RSC, and 91 patients with RC. Stage III patients with RC were further divided into 68 patients with Ra cancer (Ra, rectum/above the peritoneal reflection) and 23 patients with Rb cancer (Rb, rectum/below the peritoneal reflection). Then the 5Y-RFS and 5Y-OS were calculated for each category or subcategory. The 5Y-RFS/5Y-OS was 80.3/80.6% for Stage II patients and 63.7% (p<0.001)/66.2% (p<0.001) for Stage III patients. In the Stage II group, the survival rates were 82.9/81.2% for CC, 77.6/74.8% for RSC, and 72.9/80.5% for RC, with no significant differences between each category. In the Stage III group, the survival rates were 69.3/72.8% for CC, 71.6/77.7% for RSC, and 46.5/46.2% for RC. There was no significant difference of survival for CC vs. RSC, but significant differences were noted for CC vs. RC (p<0.001/p<0.001) and RSC vs. RC (p=0.008/p=0.007). In the Stage III group, survival rates were 71.6/77.7% for RSC, 47.6/44.8% for Ra, and 45.7/51.3% for Rb, with significant differences for RSC vs. Ra (p=0.013/p=0.005) and RSC vs. Rb (p=0.026/p=0.180), but not for Ra vs. Rb. These results suggest that Stage II/III RS cancer should be classified as colon cancer and should not be considered an independent tumor type.

Is the T1/2N1 (≤3 nodes) category actually stage IIIA (TNM)/IIIa (Japanese classification) in patients with primary colorectal cancer?

The 5-year relapse-free survival rate (5Y-RFS) and the 5-year overall survival rate (5Y-OS) were calculated for 972 patients (stage I, 206 patients; stage II, 396 patients; stage III, 370 patients). We divided the stage III group into 259 patients with IIIa/N1 disease (≤3 positive nodes) and 111 patients with IIIb/N2 disease (≥4 positive nodes) according to the Japanese classification. The IIIa/N1 and IIIb/N2 categories were each subdivided into T1/2 (stage IIIa, 45 cases; IIIb, 9 cases) and ≥T3 (stage IIIa, 214 cases; IIIb, 102 cases) according to the TNM classification, and 5Y-RFS and 5Y-OS were compared between each subcategory and each group. The 5Y-RFS/5Y-OS values calculated for each stage were as follows: stage I, 94.0/90.7%; stage II, 80.5/81.1%; stage III, 63.5/65.7%. When stage IIIa was compared with IIIb, we obtained 67.9/72.0% for stage IIIa and 53.6% (p=0.001)/50.4% (p<0.001) for stage IIIb. For stage IIIa vs. IIIb in the ≥T3 category, we obtained 63.1/68.5% for stage IIIa and 51.9% (p=0.010)/49.0% (p=0.008) for stage IIIb. For stage IIIa vs. IIIb in the T1/2 category, we obtained 92.1/92.0% for stage IIIa and 72.9% (p=0.040)/63.5% (p=0.003) for stage IIIb. There were significant differences between T1/2 and ≥T3 within stage IIIa (p=0.001/p=0.009), but not within stage IIIb. These results suggest that the T1/2N1 category of colorectal cancer should be classified as a subcategory of stage IB/Ib rather than stage IIIA (TNM)/IIIa (Japanese classification).

Occult neoplastic cells in the lymph node sinuses and recurrence/metastasis of stage III/Dukes' C colorectal cancer.

Lymph nodes from patients with colorectal cancer were immunohistochemically stained for cytokeratin to investigate the relationship between the presence of occult neoplastic cells (ONCs) and recurrence/metastasis. A total of 80 patients with stage III/Dukes' C colorectal cancer were divided into 16 patients who developed recurrence/metastasis (recurrence group) and 64 patients without recurrence (non-recurrence group). ONCs were compared between the two groups with respect to i) single cells (≥ 3 floating ONCs), ii) clusters of cells (1 or more floating aggregates of 2-20 ONCs) and iii) single cells + clusters. When single cells were detected, the sensitivity for recurrence was 87.5% (14/16, p = 0.002), the positive predictive value (PPV) was 32.6% (14/43), the specificity was 54.7% (35/64) and the negative predictive value (NPV) was 94.6% (35/37). For clusters, the sensitivity was 87.5% (14/16, p<0.001), PPV was 41.2% (14/34), specificity was 68.8% (44/64) and NPV 95.7% (44/46). With single cells + clusters, the values were 87.5% (14/16, p<0.001), 48.3% (14/29), 76.6% (49/64) and 96.1% (49/51), respectively. These results suggest that the detection of single cells + clusters is a sensitive indicator of a high risk of recurrence/ metastasis, while ONCs are useful for identifying the low-risk group of patients with stage III colorectal cancer.

Occult neoplastic cells in the lymph node sinuses and recurrence/metastasis of stage II/Dukes' B colorectal cancer.

Lymph nodes from patients with colorectal cancer were immunohistochemically stained for cytokeratin in order to investigate the relationship between the presence of occult neoplastic cells (ONCs) and recurrence/metastasis. A total of 78 patients with stage II/Dukes' B colorectal cancer were divided into two groups. The first group consisted of 18 patients who had developed recurrence/metastasis (recurrence group) and the other one of 60 patients who had survived without recurrence (non-recurrence group). The presence of ONCs was compared between the two groups with respect to i) single cells (≥3 floating ONCs), ii) clusters of cells (≥1 floating aggregates of 2-20 ONCs), and iii) single cells + clusters. When single cells were detected, the sensitivity for recurrence was 55.6% (10/18), the positive predictive value (PPV) was 30.3% (10/33), the specificity was 61.7% (37/60, p=0.195), and the negative predictive value (NPV) was 82.2%(37/45). For the clusters, the sensitivity was 55.6% (10/18), PPV was 37% (10/27), specificity was 71.7% (43/60, p=0.033), and NPV was 84.3% (43/51). With single cells + clusters, the values were 55.6% (10/18), 43.5% (10/23), 78.3% (47/60, p=0.006), and 85.5% (47/55), respectively. These results suggest that the detection of single cells + clusters has a high specificity and NPV, and indicates a low risk of recurrence/metastasis in patients with stage II colorectal cancer.

Efficacy of hybrid 2-port hand-assisted laparoscopic surgery (Mukai's operation) for patients with primary colorectal cancer.

In this study, a total of 108 patients with primary colorectal cancer who underwent hybrid 2-port hand-assisted laparoscopic surgery (HALS) were classified as 58 patients with colon cancer and 50 patients with rectal cancer. The mean operating time, mean blood loss, postoperative complications, and mean postoperative hospital stay were compared between the two groups. In patients who underwent colon cancer surgery, the mean operating time was 2 h and 26 min, the mean blood loss was 166.3 ml, and the postoperative complications were wound infection in 5/58 patients (8.6%), postoperative ileus in 3 patients (5.2%), and anastomotic stricture in 1 patient (1.7%). There was no anastomotic leakage and no conversion to conventional open laparotomy. The mean postoperative hospital stay was 12.6 days. In patients who underwent rectal cancer surgery, the mean operating time was 3 h and 38 min, the mean blood loss was 238.8 ml, and the postoperative complications consisted of wound infection in 6/50 patients (12.0%), anastomotic leakage in 3/35 patients (8.6%), anastomotic stricture in 3/47 patients (6.4%), postoperative ileus in 3/50 patients (6.0%), and conversion to conventional open laparotomy in 1/50 patients (2.0%). A covering stoma was constructed during surgery in 12/47 patients (25.5%). The mean postoperative hospital stay was 19.1 days. These results suggest that hybrid 2-port HALS (Mukai's operation) could become a standard method for the treatment of colorectal cancer, and that the long-term outcome should be compared in detail with that of standard laparotomy in the future.

Curative resection by hybrid 2-port HALS in a patient with advanced cecal cancer invading the urinary bladder: a case report.

A 67-year-old woman was referred to our department for assessment of a tumor in the right lower abdomen. Advanced cecal cancer invading the urinary bladder was diagnosed, and laparoscopy assisted colorectal surgery (LACS)-hybrid 2-port hand-assisted laparoscopic surgery (HALS) was performed in February 2008. Intraoperative laparoscopic observation revealed direct invasion of the urinary bladder by the primary tumor, so an approximately 6-cm transverse suprapubic incision was made. Under direct vision through this incision, full-thickness partial cystectomy was performed to remove the tumor invading the bladder. Then D3 right hemicolectomy was performed under pneumoperitoneum. In this patient with advanced cecal cancer invading the bladder, we performed radical curative surgery by hybrid 2-port HALS, a minimally invasive procedure in which a 6-cm incision was made in addition to the hand access site and favorable results were obtained.

Hybrid 2-port hand-assisted laparoscopic surgery for the 2-stage treatment of a complete bowel obstruction by distal sigmoid colon cancer: a case report.

In July 2008, a 40-year-old man presented to his local physician with diffuse abdominal pain and severe abdominal distension. Impending bowel rupture due to colonic obstruction was strongly suspected. Complete obstruction of the distal sigmoid colon by a tumor was diagnosed, and emergency surgery was performed. A sigmoid colon loop colostomy was created within the range of subsequent resection to relieve the obstruction. After his general condition had improved and the risks were assessed, curative resection including removal of the stoma was performed by hybrid 2-port hand-assisted laparoscopic surgery. The tumor showed invasion of the serosa without lymph node metastasis, and its pathological diagnosis was stage II. Postoperatively, mild wound infection occurred at the hand access site (stoma), but it resolved with conservative treatment, and the patient was discharged on postoperative day 13. This case is reported here because of the good results.

Clinical comparison of QOL and adverse events during postoperative adjuvant chemotherapy in outpatients with node-positive colorectal cancer or gastric cancer.

The aim of this study was to evaluate the quality of life (QOL) from the performance status (PS) and face scale (FS), and to compare adverse events (AEs) during chemotherapy in 28 patients with node-positive colorectal cancer (NP-CRC) and 15 patients with node-positive gastric cancer (NP-GC). The anticancer regimen consisted of 5-FU/LV+CPT-11 for NP-CRC and 5-FU+low-dose CDDP for NP-GC. Results were evaluated after completion of three courses. QOL evaluation revealed no significant differences between the two groups with respect to PS and FS. Among hematological AEs, grade 1/2 mild leucopenia was significantly more common in NP-CRC than NP-GC patients (p<0.05), while grade 1/2 mild thrombocytopenia was significantly more common in NP-GC than NP-CRC patients (p<0.05). Among non-hematological AEs, grade 1/2 mild neuropathy (olfactory nerve) was significantly more common in NP-CRC than NP-GC patients (p<0.05). The monthly cost for one course was approximately euro586.8 for NP-CRC patients and approximately euro181.8 for NP-GC patients. These results suggest that first-line postoperative outpatient adjuvant chemotherapy for NP-CRC and NP-GC shows no significant differences with respect to QOL, but both AEs and the cost are higher for NP-CRC than for NP-GC.

Trans-anal reinforcing sutures after double stapling for lower rectal cancer: report of two cases.

To safely avoid the construction of a covering stoma in patients with advanced lower rectal cancer undergoing laparoscopy assisted colorectal surgery (LACS), we added circumferential manual reinforcing sutures via the transanal approach at the site of mechanical anastomosis. In June 2008, LACS was performed for a tumor of 6 cm in longer diameter in the Rb region of the lower rectum approximately 5 cm from the anal verge. After intraperitoneal coloproctal anastomosis was performed in the pelvis by the double stapling technique (DST), reinforcement was provided by manual trans-anal suturing (trans-anal reinforcing sutures: TARS). A covering stoma was constructed because this was a high-risk case. Complications such as mild wound infection and stoma trouble occurred, and the patient was discharged after conservative therapy. In June 2008, LACS was performed for a tumor of 5 cm in longer diameter in the Ra region of the lower rectum approximately 7 cm from the anal verge. After intraperitoneal colorectal anastomosis was performed in the pelvis by DST, TARS were added to avoid a covering stoma. Minor leakage occurred postoperatively, but this was controlled conservatively and the patient was discharged. In patients having surgical treatment of advanced lower rectal cancer, good results were obtained by adding circumferential reinforcing sutures via the trans-anal approach at the site of ultra-low anastomosis after DST.

Comparison between intravenous and oral postoperative adjuvant immunochemotherapy in patients with stage III colorectal cancer.

This study aimed to retrospectively assess the efficacy of postoperative adjuvant chemotherapy in 77 patients who underwent curative resection for stage III colorectal cancer. They were treated by intravenous administration of 5FU + LV (FL-IV group, 38) or oral administration of UFT + PSK (oral group, 39). The 3-year relapse-free (3Y-RFS), 5-year relapse-free (5Y-RFS) and 5-year overall survival (5Y-OS) were calculated for each group, and clinical results and adverse events (AEs) were compared between the two groups. The 3Y-RFS, 5Y-RFS and 5Y-OS were 65.8, 62.7 and 72.3%, respectively, in the FL-IV group and 63.3 (p=0.7957), 56.3 (p=0.7088) and 60.4% (p=0.5293), respectively, in the oral group. These parameters showed no significant differences between the two groups. As AEs, grade 3 leucopenia, nausea/vomiting, and general fatigue were noted in one patient each (2.6%) in the FL-IV group. Grade 3 or more severe AEs were not noted in the oral group. These results suggest that oral immunochemotherapy is one of the options of postoperative adjuvant therapy for stage III colorectal cancer, because it imposes no financial burden on patients and results in high quality of life.

Comparison between intravenous and oral postoperative adjuvant immunochemotherapy in patients with stage II colorectal cancer.

The present study was designed to retrospectively examine the efficacy of postoperative adjuvant chemotherapy in 107 patients with stage II primary colorectal cancer who underwent curative resection. The chemotherapy regimen was intravenous 5FU/LV in 30 patients (FL-IV group) and oral UFT/PSK in 77 patients (oral group). There were no significant differences between the FL-IV and the oral group with respect to the 3-year relapse-free survival rate, 5-year relapse-free survival rate, and 5-year overall survival rate, which were 82.4 vs. 83.0% (p=0.8546), 78.8 vs. 80.0% (p=0.756), and 81.6 vs. 92.8% (p=0.1609), respectively. Grade 3 adverse events that occurred in the FL-IV group were leukopenia in one patient (3.3%), nausea/vomiting in two (6.6%), anorexia in two (6.6%), diarrhea in one (3.3%), and fatigue in one (3.3%). No grade 3 or 4 adverse events were observed in the oral group. These results suggest that the oral regimen achieved equivalent efficacy to the FL-IV regimen in patients with stage II colorectal cancer, while improving their postoperative quality of life.

Experimental model of two-colonoscope surgery for superficially spreading colonic tumors larger than 3 cm in the right colon.

In the present study, we experimentally examined the feasibility of two-colonoscope surgery using two types of forceps to achieve safe, reliable, and complete endoscopic mucosal resection (EMR)/endoscopic submucosal dissection (ESD) of large superficial tumors in the right colon. It was confirmed at all experimental sessions that the two pairs of forceps intersected with each other over a wide angle of at least 90 degrees in the cecum, and that the tips of the forceps could be moved by at least 180 degrees in the longitudinal and horizontal directions. In another experiment, a piece of tissue measuring 3x3 cm or larger could be safely resected from a chicken thigh as the pseudo-tumor. Based on these results, two-colonoscope surgery is considered clinically promising as a next-generation EMR/ESD technique for safe, reliable, and complete resection of superficial tumors of the right colon measuring 3 cm or more in diameter.

Local recurrence and occult neoplastic cells in the extranodal fat of dissected lymph nodes in patients with curatively resected primary colorectal cancer.

This study was designed to examine the relationship between occult neoplastic cells (ONCs) inside and outside harvested lymph nodes (intranodal/extranodal ONCs) and local recurrence in 30 patients who underwent curative resection of primary colorectal cancer. Among 10 patients with colon cancer (Dukes' A=1, Dukes' B=6 and Dukes' C=3), intranodal ONCs were positive in 1 patient (10.0%) and negative in 9 patients (90.0%), while extranodal ONCs were negative in all 10 patients (100.0%). There were no significant differences between the detection of intranodal or extranodal ONCs. Among 20 patients with rectal cancer (Dukes' A=4, Dukes' B=2 and Dukes' C=14), intranodal ONCs were positive in 5 (25.0%) and negative in 15 (75.0%), while extranodal ONCs were positive in 3 (15.0%) and negative in 17 (85.0%). There were no significant differences between the detection of intranodal or extranodal ONCs. These results suggest that patients with rectal cancer and extranodal ONCs should be followed-up carefully as a high-risk group for pelvic local recurrence. However, the prevalence of extranodal and intranodal ONCs was almost similar.

Alternating hepatic arterial infusion and systemic chemotherapy for stage IV colorectal cancer with synchronous liver metastasis.

Among 41 patients with synchronous liver metastases of colorectal cancer, 15 patients underwent synchronous resection of their liver metastases and achieved a median survival time (MST) of 1,441 days (versus 748 days for the 26 patients without resection, p=0.038), a median relapse-free survival time of 652 days (MST not reached), and a recurrence rate in the residual liver of 20% (3/15 patients). The alternating hepatic arterial infusion and systemic chemotherapy showed partial response (PR) in 6 cases, stable disease (SD) in 8 cases, and progressive disease (PD) in 1 case (n=15/26). They had an objective response rate of 40% (6/15), tumor control rate (>/= SD) of 93.3% (14/15), one-year progression-free survival rate of 35.7%, 50% time to progression of 270 days, one-year survival rate of 76.2%, and two-year survival rate of 50.8% (MST not reached). Grade 3 leucopenia was observed in 2/15 patients (13.3%). These results suggest that the present alternating therapy may become a standard regimen for patients in whom synchronous resection of liver metastases is impossible and patients who have stage IV colorectal cancer with a risk of recurrence in the remnant liver and/or at extrahepatic sites such as the lungs.