Efficacy of intraperitoneally administered paclitaxel for colorectal cancer with peritoneal metastases.

PURPOSE: Prognosis after peritoneal metastases in colorectal cancer is worse than that after lung or liver metastases. Previously, we demonstrated the safety of intraperitoneal (ip) administration of paclitaxel (PTX) combined with mFOLFOX6/CapeOX plus bevacizumab for colorectal cancer with peritoneal metastasis in a phase-I trial. Here, we evaluated the efficacy of this chemotherapy. METHODS: We enrolled six patients with histologically confirmed peritoneal metastases secondary to colorectal cancer. PTX was administered through a peritoneal access port, in combination with oxaliplatin-based systematic chemotherapy. Response rate, progression-free survival, 1-year survival rate, frequency of improvement in peritoneal cancer index (PCI), and cytology in peritoneal lavage were evaluated. This study was registered in the University Hospital Medical Information Network Clinical Trial Registry on July 1, 2016 (UNIN000022924). RESULTS: Three patients received the mFOLFOX6-bevacizumab regimen, whereas the other three received the CapeOX-bevacizumab regimen. The response rate was 25%. PCI score improved in 50% of the cases. Peritoneal lavage cytology that was positive in five patients before initiating the chemotherapy turned negative during chemotherapy in all patients. One-year survival rate was 100%, progression-free survival was 8.8 months (range, 6.8-12 months), and median survival time was 29.3 months. CONCLUSION: The ip administration of PTX with systemic chemotherapy can potentially control peritoneal metastases in colorectal cancer.

Short- and Long-term Outcomes of Minimally Invasive Versus Open Multivisceral Resection for Locally Advanced Colorectal Cancer.

BACKGROUND: Colorectal cancer invading the adjacent organs/structures is detected in 5% to 20% of all surgical interventions performed for the management of colorectal cancer. OBJECTIVE: Our purpose is to verify the safety and feasibility of laparoscopic surgery for the treatment of locally advanced colorectal cancer invading the adjacent organs. DESIGN: This is a retrospective study. SETTINGS: The study was conducted at a single institution in Japan. PATIENTS: We compared the morbidity, appropriate oncological resection, and disease-free survival of laparoscopic and open multivisceral resection in patients with colorectal carcinoma in the period between 2007 and 2015. MAIN OUTCOME MEASURES: The primary outcome measures were curative resection rate, morbidity rate, and recurrence of laparoscopic and open multivisceral resection in patients with colorectal cancer. RESULTS: Thirty-one patients received laparoscopic surgery, and 50 received open surgery. The amount of blood loss was smaller in the laparoscopic group than in the open group (60 vs 595 mL, p < 0.01). Curative surgery was performed in 46 patients of the open group (92.0%) and in 30 patients of the laparoscopic group (96.8%). Days until oral intake (5 vs 7 days, p < 0.01) and postoperative hospital stay (14 vs 19 days, p < 0.01) were shorter in the laparoscopic group. Overall morbidity was not different between the groups (22.5% vs 40.0%). Three-year disease-free survival rates were 62.7% in the open group and 56.7% in the laparoscopic group (p = 0.5776). LIMITATION: This study was a retrospective small study conducted at a single institute. CONCLUSION: Laparoscopic multivisceral resection may be a safe, less invasive alternative to open surgery, with less blood loss and shorter hospital stay, and was not inferior to open surgery based on long-term oncological end points. See Video Abstract at http://links.lww.com/DCR/A785.

Colon cancer with perforation.

Perforation of the colon is a rare complication for patients with colon cancer and usually requires emergent surgery. The characteristics of perforation differ based on the site of perforation, presenting as either perforation at the cancer site or perforation proximal to the cancer site. Peritonitis due to perforation tends to be more severe in cases of perforation proximal to the cancer site; however, the difference in the outcome between the two types remains unclear. Surgical treatment of colon cancer with perforation has changed over time. Recently, many reports have shown the safety and effectiveness of single-stage operation consisting of resection and primary anastomosis with intraoperative colonic lavage. Under certain conditions, laparoscopic surgery can be feasible and help minimize the invasion. However, emergent surgery for colon cancer with perforation is associated with a high rate of mortality and morbidity. The long-term prognosis seems to have no association with the existence of perforation. Oncologically curative resection may be warranted for perforated colon cancer. In this report, we perform a literature review and investigate the characteristics and surgical strategy for colon cancer with perforation.

Impact of Primary Tumor Location on Postoperative Recurrence and Subsequent Prognosis in Nonmetastatic Colon Cancers: A Multicenter Retrospective Study Using a Propensity Score Analysis.

OBJECTIVE: We aimed to clarify the prognostic impact of primary tumor location on recurrence after curative surgery and subsequent survival in patients with nonmetastatic colon cancer. SUMMARY OF BACKGROUND DATA: Right and left colon cancers are suggested to be oncologically different; however, their prognostic differences have been conflictingly reported. METHODS: A total of 5664 patients with curatively resected stage II-III colon cancer were reviewed, retrospectively. Relapse-free survival (RFS) after primary surgery and cancer-specific survival (CSS) after recurrence were compared between patients with right and left colon cancer. Patients' backgrounds were matched using propensity scores. RESULTS: Although patients with right colon cancer had more advanced disease, their 5-year RFS rate was significantly superior compared with that in those with left colon cancer (83.9% vs 81.1%, P = 0.019). However, the 5-year CSS after recurrence rate was significantly inferior in patients with right colon cancer compared with that in those with left colon cancer (30.6% vs 43.6%, P = 0.016). CONCLUSIONS: The primary tumor location of nonmetastatic colon cancer might have different prognostic implications for the rates of recurrence after curative resection and cancer-specific mortality after recurrence.

Laparoscopic surgery in colon cancer patients treated with chronic anti-thrombotic therapy.

BACKGROUND: Anti-thrombotic medications are commonly used for the treatment and prevention of cardiovascular diseases. Laparoscopic resection of colon cancer has generally been accepted with favorable outcomes being reported in randomized control trials. However, the safety and efficacy of laparoscopic surgery for colon cancer patients receiving chronic anti-thrombotic therapy (AT) remain unclear. METHODS: We identified 951 patients who underwent elective resection for colon cancer between 2009 and 2016 from our database. Patients were classified according to the surgical approach and chronic AT. Clinicopathological factors and surgical outcomes were analyzed between patient groups. Patients' backgrounds were matched using propensity scores in laparoscopic surgery. RESULTS: Anti-thrombotic drugs were chronically used in 135 patients. Among 714 patients who underwent laparoscopy-assisted surgery, 96 received AT. The laparoscopic approach was superior to open surgery in terms of bleeding, surgical site infections, and hospital stay in patients receiving AT. In laparoscopy-assisted surgery, the AT group patients were older and showed lower hemoglobin and albumin levels than those not receiving AT (non-AT group), and were predominantly male. After propensity score matching, estimated blood loss and operative times were similar between the two groups (93 matched patients). The frequencies of postoperative bleeding (2.2%) and thrombotic complications (0%) in the AT group did not significantly differ from those in the non-AT group (1.1 and 0%, respectively). Moreover, AT did not affect survivals. CONCLUSION: Laparoscopic approach appears to be safer and beneficial for colonic cancer patients receiving long-term AT. Bleeding and thrombotic events associated with laparoscopic surgery were not significantly affected by AT.

Successful Management of a Positive Air Leak Test during Laparoscopic Colorectal Surgery.

BACKGROUND/AIMS: Anastomotic leakage remains the most serious complications of colorectal surgery. To prevent colorectal anastomotic leakage (CAL), an air leak test (ALT) with intraoperative colonoscopy (IOCS) is performed to detect mechanically insufficient colorectal anastomoses. The approaches to an intraoperative anastomotic air leak (IOAL) have not been fully investigated. This study aimed to clarify the safe management of an IOAL in laparoscopic colorectal surgery. METHODS: One hundred forty-eight consecutive patients who underwent laparoscopic resection with double-stapling technique (DST) anastomosis for left-sided colorectal cancer between April 2015 and June 2016 were included and retrospectively reviewed. RESULTS: Intraoperative anastomotic ALT yielded positive results in 7 patients. In all 7 patients, reanastomoses were performed, and diverting stomas were constructed to protect the anastomosis in 2 patients whose reanastomosis sites were close to the anus. Three of the revised DST anastomoses showed air leakage on the repeat ALT; these sites underwent suturing repair and were confirmed to be airtight. None of the patients with a positive intraoperative ALT had postoperative CAL. The overall CAL rate was 1.4%. CONCLUSIONS: Combination management using DST revision, direct suturing repair, and a diverting stoma is recommended for intraoperative repair of anastomotic defects detected by IOCS.

Different Impacts of Preoperative Radiotherapy and Chemoradiotherapy on Oncological Outcomes in Patients with Stages II and III Lower Rectal Cancer: A Propensity Score Analysis.

BACKGROUND/AIMS: The neoadjuvant therapy for locally advanced rectal cancer has been changed from radiotherapy (RT) to chemoradiotherapy (CRT). This study is aimed at evaluating the benefit of CRT in patients with stage II or III lower rectal cancer, with regard to the impact on recurrence. METHODS: A total of 474 patients with clinical stage II or III lower rectal cancer who received either preoperative RT (n = 221) or CRT (n = 253) followed by total mesorectal excision were identified from our institutional database. Propensity score analysis was performed to mitigate selection biases. RESULTS: Among stage II patients, the CRT group showed a significantly lower 5-year local recurrence rate than the RT group (3.0 vs. 14.8%, p = 0.002). In contrast, among stage III patients, the CRT group showed a significantly lower 5-year distant recurrence rate than the RT group (27.8 vs. 42.6%, p = 0.04) and also a better 5-year recurrence-free survival (64.2 vs. 48.3%, p = 0.03). CONCLUSIONS: Addition of concurrent chemotherapy to preoperative RT significantly enhanced the local control in stage II patients and decreased distant recurrence in stage III patients. The oncological benefit of CRT may differ between patients with stage II or III rectal cancer.

Elevated risk of stoma outlet obstruction following colorectal surgery in patients undergoing ileal pouch-anal anastomosis: a retrospective cohort study.

PURPOSE: Stoma outlet obstruction (SOO) is a complication following colorectal surgery that requires stoma creation. We aimed to clarify the SOO incidence and identify risk factors for SOO after stoma surgery in patients with ulcerative colitis (UC) or rectal cancer. METHODS: The study included 345 patients with sporadic rectal cancer (n = 301) or UC (n = 44) who underwent stoma surgery between 2012 and 2017. Univariate and multivariate analyses were performed to identify risk factors for SOO. RESULTS: The SOO incidences were 27.3% (n = 12) in patients with UC and 5.6% (n = 17) in patients with sporadic rectal cancer. A multivariate analysis identified UC and loop ileostomy as independent risk factors for SOO. Subanalyses revealed that loop ileostomy was an independent risk factor for patients with UC or sporadic rectal cancer. Most patients who developed SOO were successfully managed with tube drainage through the stoma. However, stoma closure was performed earlier than originally planned in two patients. Among the 29 patients with SOO, 22 (75.9%) developed SOO within 2 weeks postoperatively; the median period between stoma creation and SOO was 6 (range 3-41) days. CONCLUSIONS: UC and loop ileostomy are independent risk factors for postoperative SOO.

Results of a 36-year surveillance program for ulcerative colitis-associated neoplasia in the Japanese population.

BACKGROUND AND AIM: Surveillance colonoscopy has been carried out for patients with long-standing ulcerative colitis who have an increased risk for colorectal cancer. The aim of the present study was to determine the incidence of and the risk factors for neoplasia. METHODS: We evaluated 289 ulcerative colitis patients who underwent surveillance colonoscopy between January1979 and December 2014. Cumulative incidence of neoplasia and its risk factors were investigated. Clinical stage and overall survival were compared between the surveillance and non-surveillance groups. RESULTS: Cumulative risk of dysplasia was 3.3%, 12.1%, 21.8%, and 29.1% at 10, 20, 30 and 40 years after the onset of ulcerative colitis, respectively. Cumulative risk of colorectal cancer was 0.7%, 3.2%, 5.2%, and 5.2% at 10, 20, 30 and 40 years from the onset of ulcerative colitis, respectively. Total colitis was a risk factor for neoplasia (P = 0.015; hazard ratio, 2.96). CONCLUSIONS: Our surveillance colonoscopy program revealed the incidence and risk factors of ulcerative colitis-associated neoplasias in the Japanese population. Total colitis is a risk factor for neoplasia.

Survival and Prognostic Factors for Metachronous Peritoneal Metastasis in Patients with Colon Cancer.

BACKGROUND: The clinical course of metachronous peritoneal metastasis of colorectal origin is poorly understood. In this retrospective study, we aimed to elucidate survival and prognostic factors for metachronous peritoneal metastasis. METHODS: Patients with metachronous peritoneal metastasis after curative resection for stage I-III colon cancer were retrospectively reviewed, and the incidence and prognosis of metachronous peritoneal metastasis were investigated. Prognostic factors were identified by univariate and multivariate analyses. RESULTS: Among 1582 surgically resected stage I-III colon cancer patients, 65 developed metachronous peritoneal metastasis. The 5-year cumulative incidence rate was 4.5%, and the median survival after diagnosis of peritoneal metastasis was 29.6 months. None of the patients underwent peritonectomy or intraperitoneal chemotherapy. Independent prognostic factors included right colon cancer [hazard ratio (HR) 2.69, 95% confidence interval (CI) 1.26-5.64; p = 0.011], time to metachronous peritoneal metastasis of <1 year (HR 2.02, 95% CI 1.04-3.87; p = 0.040), Peritoneal Cancer Index (PCI) >10 (HR 3.68, 95% CI 1.37-8.99; p = 0.012), concurrent metastases (HR 4.09, 95% CI 2.02-8.23; p < 0.001), and peritoneal nodule resection (HR 0.31, 95% CI 0.13-0.65; p = 0.002). CONCLUSIONS: A proportion of colon cancer patients with metachronous peritoneal metastasis may benefit from combined peritoneal nodule resection and systemic chemotherapy. Right colon cancer, early peritoneal metastasis, a high PCI, and concurrent metastases negatively affected prognosis in patients with metachronous peritoneal metastasis.

Characterization of Conversion Chemotherapy for Secondary Surgical Resection in Colorectal Cancer Patients with Lung Metastases.

OBJECTIVE: Clinical trials demonstrated that 6-37% of the patients with colorectal liver-limited metastases underwent surgical resection after first-line chemotherapy. However, limited information is available on the conversion of colorectal cancer patients with lung metastases to resection by systemic chemotherapy. METHODS: We retrospectively investigated 156 patients with unresectable colorectal cancer who received oxaliplatin- or irinotecan-based first-line systemic chemotherapy with or without antibodies in our department between January 2007 and December 2015. The conversion rate to surgery and chemotherapeutic regimens and periods were analyzed with respect to the target organ. RESULTS: In addition to 4 patients who achieved complete response, 73 exhibited tumor shrinkage of any extent. Twenty patients underwent secondary surgery, all of whom received targeting antibodies. In 75 patients with liver metastases, 18 (24%) were converted to resection after chemotherapy for a median of 110 days. In contrast, 4 (7%) out of 56 patients with lung metastases underwent resection after chemotherapy for a median of 449 days. Conversion was an independent prognostic factor in patients with lung metastases. CONCLUSION: The conversion rate to resection was lower for colorectal cancer patients with lung metastasis by systemic chemotherapy, which required a longer duration than for those with liver metastases.

Brain Metastasis from Colorectal Cancer: Predictors and Treatment Outcomes.

OBJECTIVE: Difficulties are associated with the management of brain metastasis (BM), which portends a poor prognosis in the treatment of colorectal cancer (CRC). The aim of the present study was to identify risk factors for BM in CRC and evaluate the outcomes of various treatment modalities. METHODS: We retrospectively reviewed data on a total of 2,238 patients with primary CRC who underwent surgical resection at our hospital between 1999 and 2014. Predictive factors for BM and prognostic factors after the diagnosis of BM were examined by univariate and multivariate analyses using Cox proportional hazards models. RESULTS: Three patients (0.1%) had BM at the initial diagnosis, and 23 patients (1.2%) developed metachronous BM during the median follow-up period of 44.6 months. Lung and bone metastases were identified as independent predictive factors for BM. Median survival after the diagnosis of BM was 7.4 months. Stereotactic radiosurgery, administered to 41% of the patients with BM, was associated with a better postdiagnostic survival. CONCLUSION: CRC patients with metastasis to the lung or bone were at a higher risk of BM. Because the survival is still limited, it is crucial to determine the treatment strategy in consideration of the characteristics of each therapy and quality of life in CRC patients with BM.

Diagnosis, Assessment, and Therapeutic Strategy for Colorectal Mixed Adenoneuroendocrine Carcinoma.

Colorectal mixed adenoneuroendocrine carcinoma (MANEC), which acts like an aggressive tumor, is a rare clinical manifestation on which only a limited amount of literature exists. Surgical resection by regional lymphadenectomy is considered as the only curative treatment for colorectal MANEC, and adjuvant chemotherapy or radiotherapy is recommended because of its high recurrence rate. Colorectal MANEC is frequently diagnosed at an advanced stage, when it is unresectable, and chemotherapy plays a central role in its treatment. Pathological confirmation of the target lesion component is critical for regimen selection. If the lesion comprises an adenocarcinomatous component, a regimen for colorectal adenocarcinoma should be administered. For lesions comprising mainly a neuroendocrine carcinomatous component, cisplatin combined with etoposide or irinotecan has proven to be clinically appropriate. Everolimus, a mechanistic target of rapamycin pathway inhibitor, also improves survival. Sunitinib malate, another molecular targeting agent, is effective for treating neuroendocrine carcinoma; however, the evidence on its effectiveness for treating gastrointestinal neuroendocrine carcinoma is insufficient.

A high preoperative carbohydrate antigen 19-9 level is a risk factor for recurrence in stage II colorectal cancer.

BACKGROUND: Many risk factors for recurrence in stage II colorectal cancer (CRC) have been proposed, and the efficacy of adjuvant chemotherapy is still controversial. This study aimed to identify risk factors for tumor recurrence and assess whether they are related to the benefits of adjuvant chemotherapy in stage II CRC. MATERIAL AND METHODS: Patients with stage II CRC that was curatively operated on in a tertiary hospital between 2005 and 2014 were analyzed. Cox's proportional hazards models were applied to identify risk factors for recurrence and overall mortality. Kaplan-Meier methods were used to evaluate whether adjuvant chemotherapy was beneficial in terms of recurrence-free survival (RFS). RESULTS: A total of 384 patients were identified, among whom 38 (10%) received adjuvant chemotherapy. In a median follow-up of 48.6 months, 52 patients (14%) developed recurrence. Multivariate analyses identified two independent parameters that significantly decreased RFS; pathological T4 [hazard ratio (HR), 2.34; 95% confidence interval (CI), 1.31-4.15; p = .0045) and preoperative carbohydrate antigen (CA) 19-9 > 37 U/ml (HR 1.96; 95% CI 1.02-3.58; p = .045). These factors also inversely correlated with overall survival; T4: HR 2.10, p = .019) and CA 19-9 > 37 U/ml (HR 2.15, p = .025). The combination of T4 and CA 19-9 > 37 U/ml resulted in an increased HR (3.52) for recurrence. However, adjuvant chemotherapy did not improve RFS in patients with these features. CONCLUSION: The present study demonstrated elevated CA 19-9 levels as well as T4 independently predicted worse long-term outcomes in patients with stage II CRC. However, the characterization of patients who gain survival advantages by adjuvant chemotherapy requires further investigation.

Adiponectin and colorectal cancer.

Colorectal cancer is an obesity-related malignancy. Adiponectin is an adipokine produced exclusively by adipose tissue, and its concentration in the serum is reduced in obesity. A low serum level of adiponectin is associated with an increased risk of various types of malignancies including colorectal cancer. These facts suggest that the epidemiological link between obesity and cancer may have a significant association with adiponectin. Although numerous studies of colorectal cancer have been reported, the results are conflicting about the anti-cancer effect of adiponectin, and how adiponectin affects carcinogenesis or cancer development remains controversial. Because adiponectin has multiple systemic effects and exists as a high serum concentration protein, the main role of adiponectin should be regulation of homeostasis, and it would not likely act as an anti-cancerous hormone. However, as epidemiological evidence shows, a low adiponectin level may be a basic risk factor for colorectal cancer. We speculate that when the colonic epithelium is stimulated or damaged by another carcinogen under the condition of a low adiponectin level, carcinogenesis is promoted and cancer development is facilitated. In this report, we summarize recent findings of the correlation between adiponectin and colorectal cancer and investigate the effect of adiponectin on colorectal cancer.

Laparoscopic versus open surgery for obese patients with rectal cancer: a retrospective cohort study.

PURPOSE: To evaluate the advantages of laparoscopic surgery for rectal cancer in obese patients. METHODS: We collected clinical data from consecutive patients who underwent anterior resection for rectal cancer between 2008 and 2015 to compare the surgical outcomes of a laparoscopic surgery group (LG) with those of an open surgery group (OG) stratified by obesity. Obesity was defined as a body mass index ≥25. RESULTS: A total of 268 patients were analyzed, with 157 in the LG (44 obese and 113 non-obese) and 111 in the OG (25 obese and 86 non-obese). The rates of complications between the LG and the OG were 18.5 vs. 11.6 % (p = 0.18) for the non-obese patients and 18.2 vs. 20.0 % (p = 1.0) for the obese patients, respectively, without a significant difference. Operative time was longer in the LG than in the OG, but the difference between the non-obese and obese patients was not significant, being 266 vs. 189 min (p < 0.0001) and 260 vs. 254 min (p = 0.96), respectively. Blood loss was much lower in the LG for both obese and non-obese patients, being 10 vs. 435 mL (p < 0.0001) and 10 vs. 275 mL (p < 0.0001), respectively. CONCLUSION: There were no significant differences between LG and OG in operative time or complications for obese patients with rectal cancer, and blood loss was much lower in the LG. Thus, laparoscopic surgery is a safe and minimally invasive approach for obese patients with rectal cancer.

Anatomy of the middle rectal artery: a review of the historical literature.

The middle rectal artery is a very important anatomical structure in rectal cancer surgery. It is the only vessel that penetrates through the proper rectal fascia into the pelvic cavity, and therefore threatens the integrity of total mesorectal excision. Moreover, it is very closely related to the lateral lymphatic drainage root. The definition of the middle rectal artery is ambiguous, and different frequencies, origins, and trajectories have been reported in various papers. The frequency of the middle rectal artery is reported to range from 12 to 97 %. Traditionally, the middle rectal artery is described as an artery that penetrates the pelvic plexus from the lateral side along with the lateral ligament; the frequency of this lateral type of middle rectal artery ranges from 20 to 30 %. However, the reports that describe higher frequency values also consider another type of middle rectal artery, which penetrates the neuro-vascular bundle from the antero-lateral direction; this antero-lateral type of middle rectal artery tends to be a small vessel, and frequently forms a common trunk with the prostatic artery. With advancements in endoscopic surgery, the knowledge of the precise anatomy of this structure is becoming more crucial for optimal rectal cancer surgery.

CD133 Expression at the Metastatic Site Predicts Patients' Outcome in Colorectal Cancer with Synchronous Liver Metastasis.

BACKGROUND: CD133 is a transmembrane protein that is proposed to be a stem cell marker of colorectal cancer (CRC); however, the correlation between CD133 expression and survival of CRC patients with liver metastasis has not been fully examined. METHODS: CD133 expression was evaluated immunohistochemically, both in primary tumors and synchronous liver metastases of 88 consecutive CRC patients, as well as recurrent lesions in the remnant liver of 27 of these 88 patients. The relationship between CD133 expression and clinicopathological characteristics, recurrence-free survival, and overall survival (OS) was analyzed. RESULTS: CD133 expression in liver metastases (mCD133) was detected in 50 of 88 patients (56.8 %), and had significant correlation with CD133 expression in primary lesions (pCD133) (p < 0.001). CD133 expression in liver recurrent lesions (recCD133) also had a significant correlation with mCD133 (p < 0.001). mCD133+ patients had significantly longer disease-free survival (p = 0.043) and OS (p = 0.014) than mCD133- patients. In addition, mCD133+ patients had a significantly lower rate of extrahepatic recurrence (p < 0.001). CONCLUSIONS: Patients without CD133 expression in liver metastasis had significantly shorter survival, perhaps because mCD133- patients had a significantly higher rate of extrahepatic recurrence.

Paradoxical Reductions in Serum Anti-p53 Autoantibody Levels by Chemotherapy in Unresectable Colorectal Cancer: An Observational Study.

OBJECTIVE: The anti-p53 autoantibody is an emerging tumor marker that is commonly produced in response to p53 mutations. The usefulness of this antibody has been suggested in screening for and the monitoring of recurrence in colorectal cancer; however, its significance as a marker during chemotherapy remains largely unknown. METHODS: We measured serum anti-p53 antibody levels in patients with unresectable colorectal cancer who underwent first-line systemic chemotherapy. Tumor responses were evaluated by computed tomography. We determined whether temporal changes in this antibody during therapy are associated with radiological responses. RESULTS: Of the 83 patients in our study, 29 (35%) had elevated serum anti-p53 antibody levels before chemotherapy. Among these, antibody levels decreased in all 14 responders. In contrast, among those patients with elevated pretherapeutic serum anti-p53 antibody levels, 89% showed a paradoxical decrease in antibody levels and exhibited disease progression after chemotherapy. Moreover, serum anti-p53 antibody levels before and after chemotherapy were not associated with survival. CONCLUSION: These results suggest that serum anti-p53 antibody levels are of limited value in the evaluation of responses to palliative chemotherapy in patients with colorectal cancer.

Evaluation of the vascular anatomy of the right-sided colon using three-dimensional computed tomography angiography: a single-center study of 536 patients and a review of the literature.

PURPOSE: The requisite for a rigorous preoperative understanding of vascular branching continues to grow in parallel with the implementation of laparoscopic surgery. Three-dimensional (3D)-computed tomography (CT) angiography is a less-invasive modality than traditional angiographic examination. Therefore, we aimed to evaluate branching patterns of the superior mesenteric artery (SMA). METHODS: In the present study, 536 consecutive patients who underwent preoperative 3D-CT angiography from April 2012 to March 2014 were prospectively enrolled. The branching pattern of the right colic artery (RCA) and the intersectional patterns of the RCA, ileocolic artery (ICA), and superior mesenteric vein (SMV) were evaluated. RESULTS: The RCA existed in only 179 cases (33.4 %); the remaining 357 patients (66.6 %) lacked evidence of the RCA. The ICA was detected in all cases. The RCA ran ventral to the SMV in the majority of cases (89.4 %). Conversely, the ICA ran ventral to the SMV in only half of the cases (50.6 %). When the RCA was observed to pass dorsal to the SMV, the ICA also ran dorsal to SMV in all cases. CONCLUSIONS: 3D-CT angiography can aid surgeons in identifying and understanding the anatomical vascular variations and intersectional patterns of the RCA, ICA, and SMV. Developing awareness of these variations can aid in the prevention of unexpected vascular injury during laparoscopic right-sided colon surgery.