Randomized controlled trial comparing cosmetic results of midline incision versus off-midline incision for specimen extraction in laparoscopic colectomy.

PURPOSE: A notable advantage of laparoscopic colorectal surgery is that only a small incision at the extraction site is necessary, which is considered to be cosmetically beneficial. Meanwhile, the optimal extraction site for the resected specimen in laparoscopic colectomy is controversial in terms of cosmetic benefit. This randomized controlled trial compares midline and off-midline extraction sites in laparoscopic colectomy in patients with colon cancer, with consideration of cosmetic benefits as the primary endpoint. METHODS: Included were patients that underwent elective laparoscopic colectomy at WMUH between October 2014 and February 2017. Patients were randomly assigned to either midline incision group or off-midline incision group. Prospectively collected data included cosmetic results (patients and observer assessment scale) and complications including incidence of incisional hernia, SSI, and pain. This trial was registered with UMIN Clinical Trials (UMIN000028943). RESULTS: Finally, 98 patients with colorectal cancer were analyzed. No significant differences were found between the two groups in patient and observer assessment scales of cosmetic results (midline 8 ± 1.1 vs off-midline 11 ± 5.9 p = 0.16, midline 13.5 ± 6.6 vs off-midline 15 ± 11 p = 0.58, respectively) or in postoperative pain. However, incisional hernia occurred in four cases in the midline group (8%), which was significantly higher than that in the off-midline group (no cases, 0%). CONCLUSION: There was no significant difference in terms of cosmetic benefit, the primary endpoint, between the two groups. In this study, only the extraction site location was compared; future studies will examine differences depending on the incisional direction, including the incidence of incisional hernia.

Histology of metastatic colorectal cancer in a lymph node.

BACKGROUND: A primary colorectal cancer (CRC) tumor can contain heterogeneous cancer cells. As clones of cells with different properties metastasize to lymph nodes (LNs), they could show different morphologies. Cancer histologies in LNs of CRC remains to be described. METHODS: Our study enrolled 318 consecutive patients with CRC who underwent primary tumor resection with lymph node dissection between January 2011 and June 2016. 119 (37.4%) patients who had metastatic LNs (mLNs) were finally included in this study. Cancer histologies in LNs were classified and compared with pathologically diagnosed differentiation in the primary lesion. The association between histologies in lymph node metastasis (LNM) and prognosis in patients with CRC was investigated. RESULTS: The histologies of the cancer cells in the mLNs were classified into four types: tubular, cribriform, poorly differentiated, and mucinous. Same degree of pathologically diagnosed differentiation in the primary tumor produced various histological types in LNM. In Kaplan-Meier analysis, prognosis was worse in CRC patients with moderately differentiated adenocarcinoma who had at least some mLN also showing cribriform carcinoma than for those whose mLNs all showed tubular carcinoma. CONCLUSIONS: Histology in LNM from CRC might indicate the heterogeneity and malignant phenotype of the disease.

Elective colorectal cancer surgery in nonagenarians and postoperative outcomes.

OBJECTIVES: The population of very elderly patients is increasing, and nonagenarians have significantly higher mortality rates and poorer rates of survival than younger patients. Meanwhile, recent studies have shown colorectal cancer surgery in nonagenarian patients to be feasible regarding postoperative outcomes. This retrospective study aims to evaluate the postoperative outcomes of nonagenarians in the latest clinical settings. METHODS: Consecutive nonagenarian patients who underwent elective colorectal cancer surgery between 2018 and 2020 retrospectively enrolled (Trial registration number: UMIN000046296 on December 7th, 2021). Clinicopathological data and short-term postoperative outcomes were collected for statistical analysis. RESULTS: This study included 81 nonagenarian patients (31 males, 50 females). Postoperative complications occurred in 21 patients (25.9%), and 3 patients died within 90 days (3.7%). Multivariate analysis revealed prognostic nutritional index was a significant predictor of postoperative complications (OR 2.99, 95% CI 0.78-9.10, P = 0.048), and performance status ≥ 3 could be an independent risk factor of 90-day mortality (HR 32.30, 95% CI 3.20-326.10, P = 0.032). CONCLUSIONS: Short-term outcomes after surgical treatment for nonagenarian patients with colorectal cancer were acceptable. Low prognostic nutritional index was closely related to postoperative complications and poor performance status could also lead to 90-day mortality. In aging populations, risk stratification to prevent poorer postoperative outcomes in nonagenarian patients is needed.

New diagnostic strategy using narrow-band imaging (NBI) during laparoscopic surgery for patients with colorectal cancer.

BACKGROUND: Accurate tumor stage diagnosis during laparoscopic surgery remains difficult. We clarify the impact of new diagnostic strategy using narrow-band imaging (NBI) during laparoscopic surgery for colorectal cancer compared with other strategies. METHODS: We defined angiogenesis (Ag) and fibrosis (Fib) grades using NBI laparoscopy (lap-NBI), and assessed the clinicopathological features associated with these grades for 67 patients with colorectal cancer who underwent surgery. We assessed vessel density and gray scale with computer software. RESULTS: NBI-Ag-grade and NBI-Fib-grade of the serosal surface of cancer lesions and peritoneal nodules correlated with vessel density and gray scale of those assessed by Image J computer software. NBI-Fib-grades of liver nodules also correlated with gray scale. NBI-Ag- grade and Fib-grade of the serosal surface of cancer lesions correlated with pathological depth of invasion. These NBI grades of pathological metastatic peritoneal nodules were higher than those of pathologically benign peritoneal nodules. NBI- Fib grades of pathological metastatic liver nodules were higher than those of pathologically benign liver nodules. In multivariate analysis, lap-NBI was associated with different diagnosis for T3, T4 and non-T3, and non-T4. Moreover, lap-NBI was associated with different diagnosis for T4 and non-T4. Predictive value for T4 by lap-NBI showed high sensitivity (85%) specificity (87%), positive predictive value (74%), negative predictive value (93%), and overall accuracy (87%). Sensitivity and overall accuracy of lap-NBI was superior to that of other diagnostic modalities. CONCLUSION: We clarified the usefulness of the new diagnostic strategy using lap-NBI during laparoscopic surgery for colorectal cancer in comparison with other strategies.

High visceral to subcutaneous fat area ratio predicts early postoperative small bowel obstruction after surgery for colorectal cancer.

PURPOSE: Risks for postoperative small bowel obstruction have been demonstrated in several reports, most of which indicated male sex was a risk factor, but with the reason remaining unknown. We tested the hypothesis that it could be because males have more visceral fat than females. This prospective observational study aims to examine risks of early postoperative small bowel obstruction (EPSBO) after colorectal cancer surgery and the association between visceral to subcutaneous fat area ratio (V/S ratio) and EPSBO. METHODS: Four hundred and seventy-four patients who underwent colectomy for colorectal cancer in our hospital were enrolled in this study. The influence of several factors including V/S ratio on the development of EPSBO was analyzed. RESULTS: Thirty-one of the 474 patients (6.5%) developed EPSBO. EPSBO occurred more frequently in males (p = 0.03) and cases who developed postoperative anastomotic leakage (p < 0.001) or wound infection (p = 0.02). Higher V/S ratio was strongly related to male sex (p < 0.001). Multivariate analysis revealed higher V/S ratio (OR 2.25; p = 0.049) and anastomotic leakage (OR 5.86; p < 0.001) were independent risk factors for EPSBO. CONCLUSION: Higher V/S ratio was significantly related to EPSBO, suggesting that one of the reasons EPSBO was more likely to occur in males because they have more visceral fat than females. Preoperative identification of this risk factor could help us watch out for this potential complication.

Asymptomatic patent processus vaginalis is a risk for developing external inguinal hernia in adults: A prospective cohort study.

BACKGROUND: Inguinal hernia repair is common for children and adults across the world, but the mechanism behind hernia onset still requires elucidation. This prospective study aims to determine whether patent processus vaginalis (PPV) is a factor in the development of external inguinal hernias. METHOD: We enrolled 1008 patients who underwent laparoscopic surgery and in whom the inguinal region was observed. If processus vaginalis existed, we measured the diameter and length. Patients were followed for three years after surgery to investigate the incidence of external inguinal hernias. RESULT: No significant differences were found between age groups. Furthermore, no difference could be recognized in length or opening diameter of the PPVs between age groups. Three-year follow up was possible for 765 of 1008 patients enrolled in this study (76%), eight of whom, all male, developed external inguinal hernia during this period. Multivariate analysis for onset of inguinal hernia onset in male patients showed that PPV and length of the right PPV were independent risk factors for development of external inguinal hernia. CONCLUSION: The patency rate, length, and diameter of the processus vaginalis do not differ according to age. The patency of the processus vaginalis in male patients is an independent risk factor for development of external inguinal hernia in adults.

Preoperative detection of KRAS mutated circulating tumor DNA is an independent risk factor for recurrence in colorectal cancer.

Preoperative ctDNA status in relation to recurrence in cases of CRC remains unclear. We examined preoperative ctDNA detection by targeting KRAS gene mutations as a predictive marker for recurrence after CRC surgery. We measured the preoperative KRAS mutated ctDNA status and analyzed the correlation with clinicopathologic features of 180 patients that underwent surgery for CRC. We studied the association between preoperative KRAS mutated ctDNA and postoperative recurrence in patients (n = 150) that underwent radical surgery. KRAS mutated ctDNA was detected in 59 patients (32.8%). Median mutant allele frequency of KRAS in ctDNA was 0.20%. KRAS status in ctDNA and lymph node metastasis and distant metastasis were not significantly different. Among patients that underwent radical resection, recurrence occurred in 21 (14.0%, median follow-up 24 months). In Kaplan-Meier analysis, preoperative detection of KRAS mutated ctDNA was associated with inferior recurrence-free interval (RFI) (p = 0.002) and recurrence-free survival (RFS) (p = 0.025). In a multivariate Cox proportional hazards model, preoperative detection of KRAS mutated ctDNA was an independent factor related to both RFI (HR = 3.08; p = 0.012) and RFS (HR = 2.18; p = 0.044). Preoperative measurement of KRAS mutated ctDNA could be useful to decide postoperative treatment.

Intraoperative maneuvers may affect the development of early postoperative small bowel obstruction after laparoscopic colorectal cancer surgery: Multicenter prospective cohort study.

BACKGROUND: Early postoperative small bowel obstruction (EPSBO) is one of the most common complications after colorectal cancer (CRC) surgery, and clarification of its causes is desired. Several reports have demonstrated the risks of EPSBO, but few have focused on laparoscopic surgery for CRC and intraoperative maneuvers. We therefore prospectively examined the risk factors for EPSBO after laparoscopic CRC resection. METHODS: We prospectively enrolled 706 patients with CRC that underwent laparoscopic CRC resection in our hospital and affiliated hospitals. We analyzed several factors concerning EPSBO including intraoperative procedures. RESULTS: EPSBO developed in 43 of the 706 cases (6.1%). Univariate analysis showed that risk factors for EPSBO were male sex, increased operative time, repositioning of the small intestine before wound closure and anastomotic leakage. Risk factors for EPSBO according to multivariate analysis were increased operative time (odds ratio (OR) 2.41; P = 0.032), repositioning of the small intestine before wound closure (OR 3.58; P = 0.005) and anastomotic leakage (OR 3.91; P = 0.006). CONCLUSION: To reduce EPSBO after laparoscopic CRC surgery, the operation should be finished as soon as possible without performing optional maneuvers. To avoid development to EPSBO, particular care is required in cases where the risk of anastomotic leakage is predicted to be high.

Origin and adaptation of green-sensitive (RH2) pigments in vertebrates.

One of the critical times for the survival of animals is twilight where the most abundant visible lights are between 400 and 550 nanometres (nm). Green-sensitive RH2 pigments help nonmammalian vertebrate species to better discriminate wavelengths in this blue-green region. Here, evaluation of the wavelengths of maximal absorption (λmax s) of genetically engineered RH2 pigments representing 13 critical stages of vertebrate evolution revealed that the RH2 pigment of the most recent common ancestor of vertebrates had a λmax of 503 nm, while the 12 ancestral pigments exhibited an expanded range in λmax s between 474 and 524 nm, and present-day RH2 pigments have further expanded the range to ~ 450-530 nm. During vertebrate evolution, eight out of the 16 significant λmax shifts (or |Δλmax | ≥ 10 nm) of RH2 pigments identified were fully explained by the repeated mutations E122Q (twice), Q122E (thrice) and M207L (twice), and A292S (once). Our data indicated that the highly variable λmax s of teleost RH2 pigments arose from gene duplications followed by accelerated amino acid substitution.

Quantitative Indocyanine Green Fluorescence Imaging Used to Predict Anastomotic Leakage Focused on Rectal Stump During Laparoscopic Anterior Resection.

Background: Anastomotic leakage (AL) is arguably the most troublesome complication of anterior resection (AR). In recent years, however, indocyanine green (ICG) fluorescence imaging has been recently used to evaluate blood flow in the anastomosis site, and it has been suggested that AL may be predicted. We reported the effectiveness of predicting AL in colorectal cancer surgery by observing a quantitative laparoscopic ICG fluorescence imaging for the first time. The purpose of this study was to predict the risk of postoperative AL by quantitative laparoscopic ICG fluorescence imaging focused on the rectal stamp, which is one of the major causes of AL in AR, and to construct diverting stoma (DS) only in appropriate cases. Methods: We studied the 25 patients who underwent elective laparoscopic AR for rectal cancer at our hospital between July 2016 and June 2017. Before enforcing double-stapling technique anastomosis, we injected ICG intravenously, and laparoscopically evaluated blood flow on the rectal stump. We analyzed quantitatively the relationship between various parameters and AL. Results: Median T0, from when the ICG was injected intravenously and the ICG disappeared from the injection route to the rise of the histogram of intensity, in AL group was significantly longer than that in non-AL group (P = .03). There were no other significant differences between AL and non-AL groups. Conclusions: T0 was longer in patients with AL than in those without. If prolonged T0 can be recognized intraoperatively, it will be possible to construct DS for appropriate patients only.

Modulation of capecitabine administration to improve continuity of adjuvant chemotherapy for patients with colorectal cancer: A phase II study.

Adjuvant chemotherapy with capecitabine is frequently not completed due to adverse events, including hand-foot syndrome. A higher completion rate of capecitabine by reduction of the side effects may improve disease-free survival and quality of life of affected patients. In the present study, colorectal cancer (CRC) patients were treated with capecitabine (2,500 mg/m2/day), which was taken for five days, followed by an interval of two days (5-days-on/2-days-off schedule). One course lasted three weeks, and eight courses (24 weeks) were administered. The median number of treatment courses was significantly higher in patients in the 5-days-on/2-days-off regimen group compared with that of patients in the retrospectively included conventional regimen group (P=0.0438). The frequency of completion of the scheduled treatment by patients in the 5-days-on/2-days-off regimen group was significantly higher (P=0.0389). The present phase II study suggests that toxicities associated with the 5-days-on/2-days-off regimen are lower compared with those of the conventional regimen, and that the occurrence of adverse events was higher, but less high-grade toxicities were reported. The time to treatment failure was also favorable in the new regimen and it demonstrated good feasibility. In conclusion, the present study demonstrated good feasibility with retained quality of life and acceptable adverse effects (mostly low-grade), and the 5-days-on/2-days-off regimen should be further evaluated in future randomized controlled trials. The present study was registered in the University Hospital Medical Information Network (UMIN) clinical trial registry (no. UMIN000012813).

Loss of CEACAM1 is associated with poor prognosis and peritoneal dissemination of patients with gastric cancer.

CEACAM1 is associated with malignant potential of various cancers. The current study aims to clarify the association between carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) expression and malignant potential of gastric cancer and to address whether CEACAM1 cytoplasmic domain isoform balance modulates the properties of gastric cancer cells. Immunohistochemical analyses for CEACAM1 were performed in 235 patients with gastric cancer who underwent surgery. Risk factors for overall survival and peritoneal metastasis were calculated based on CEACAM1 expression in the gastric cancer tissue. Patients with CEACAM1 long (CEACAM1-L) or short (CEACAM1-S) cytoplasmic isoform dominance were compared with patients with null CEACAM1 expression in terms of overall survival. CEACAM1 transfected or knockdown gastric cancer cell line, NUGC3 and MKN7 cells, were examined by invasion assay and three dimensional (3D) culture, in order to clarify whether CEACAM1 modulate invasion, lumen formation and tumor growth of gastric cancer cells. Multivariate analysis demonstrated that gastric cancer without CEACAM1 is an independent prognostic factor and a risk factor for peritoneal dissemination. Patients with CEACAM1-S dominance had better prognosis than those with CEACAM1-L. CEACAM1-4L overexpression induced less invasion, more lumen formation, and less tumor growth of NUGC3 cells. CEACAM1-4S overexpression had less invasion and more lumen formations, but not less tumor growth. Knockdown of CEACAM1 expression had less invasion, but not less lumen formations of MKN7 cells. Loss of CEACAM1 is associated with poor prognosis and peritoneal dissemination of patients with gastric cancer. Expression of CEACAM1 in gastric cancer cells modulates invasiveness, lumen formation, and tumor growth.

Mass-forming mucosa-associated lymphoid tissue lymphoma of the cecum treated by laparoscopy-assisted bowel resection.

Colonic mucosa-associated lymphoid tissue (MALT) lymphoma is very rare, especially those which form a mass. Although the characteristics and treatment methods of gastric MALT lymphomas are well established, those of colonic MALT lymphomas have been insufficiently described. Here, we report a case of mass-forming cecal MALT lymphoma that was successfully treated by laparoscopy-assisted bowel resection. A 60-year-old woman with right lower abdominal pain and a palpable tumor was referred to our hospital. Colonoscopy showed a smooth elevated submucosal tumor-like lesion in the cecum. Histological and immunochemical findings were consistent with MALT lymphoma. Serum tumor marker levels were within normal range. Enhanced abdominal computed tomography showed a large tumor 55 mm in diameter in the cecum and edema of a few paracolic lymph nodes. The tumor was diagnosed as cecal MALT lymphoma classified as stage II1 by Lugano classification, and laparoscopy-assisted ileocecal resection was performed. The postoperative course was uneventful and the patient underwent eradication therapy for Helicobacter pylori. A year after the operation she has had no recurrence. In patients with mass-forming colonic MALT lymphoma without dissemination, surgical resection may be a feasible treatment.

Defunctioning loop ileostomy for rectal anastomoses: predictors of stoma outlet obstruction.

PURPOSE: Creation of defunctioning loop ileostomy is a standard procedure in laparoscopic lower rectal surgery. Stoma-related obstruction sometimes occurs, but its cause has not been fully analyzed. This study aims to assess stoma obstructive complications and clarify the risk factors of stoma-related obstructions. METHODS: Two hundred and thirty consecutive patients who underwent laparoscopic rectal cancer surgery with defunctioning loop ileostomy between April 2007 and December 2017 were recruited, numbering 230. We statistically examined the frequency and risk factor of stoma outlet obstruction. RESULTS: Postoperative stoma-related complications developed in 41 patients (17.8%) overall, and there was no 30-day mortality. Stoma outlet obstructions occurred in 16 patients (7.0%) during postoperative course. Thick subcutaneous fat at the stoma-marking site (vertical distance ≥ 20 mm) and body mass index (≥ 22.2) were significantly associated with the risk of stoma outlet obstruction in univariate analysis. Thick subcutaneous fat was a significant predictive factor of stoma outlet obstruction according to multivariate analysis (odds ratio 3.80). CONCLUSIONS: This report investigates significant predictors of stoma outlet obstruction in laparoscopic rectal cancer surgery for the first time. In laparoscopic procedure, stoma outlet obstruction should be particularly considered in obese patients who have especially thick subcutaneous fat of the abdominal wall.

Alpha-fetoprotein-producing rectal cancer successfully responded to preoperative chemoradiotherapy: case report.

BACKGROUND: Alpha-fetoprotein (AFP) is produced by some tumors, such as hepatocellular carcinoma and yolk sac tumors, leading to an increase in serum AFP level. However, AFP in colorectal cancer is extremely rare. Treatment for AFP-producing cancer is often performed according to conventional methods, but oncological outcomes of both surgery and chemotherapy are poor. We report a case of a patient with AFP-producing rectal cancer which successfully responded to preoperative chemoradiotherapy. CASE PRESENTATION: Rectal tumor was diagnosed in a 68-year-old man referred to our hospital. Colonoscopy showed a type 2 tumor in the lower rectum, and biopsy revealed an adenocarcinoma with enteroblastic differentiation. Serum tumor marker levels were 8.8 ng/ml in carcinoembryonic antigen (CEA) and 28.3 ng/ml in AFP. Clinical diagnosis was stage IIIB (T3N1M0), and preoperative chemoradiotherapy was performed to prevent local recurrence. Effective tumor reduction was observed, and serum tumor marker levels decreased to normal range. Low anterior resection with temporary diverting ileostomy was performed, and histology revealed residual adenocarcinoma. Pathological diagnosis was stage I (T2N0M0). The tumor was found to be an AFP-producing adenocarcinoma on further immunohistopathological examination. The postoperative course was uneventful, and the patient received adjuvant chemotherapy for 3 months. CONCLUSIONS: The outcomes of preoperative chemoradiotherapy against AFP-producing rectal cancer are reported here for the first time. Based on our experience with this patient, it appears preoperative chemoradiotherapy for patients with AFP-producing advanced rectal cancer is feasible.

Successful laparoscopic resection for cap polyposis: case report, literature review.

BACKGROUND: Cap polyposis is a rare gastrointestinal disease with endoscopically and pathologically distinctive features. Its exact etiology has not been fully elucidated. In a few cases, there was recurrence after inadequate treatment. Efficacy of Helicobacter pylori eradication therapy, however, has been shown in some published research. CASE PRESENTATION: A 70-year-old female patient developed intermittent mucous diarrhea with loss of body weight and visited a physician. Total colonoscopy showed multiple sessile polyps which were partially coadunated from the rectum to the sigmoid colon. Histopathological finding was tubular adenoma with mild atypia. The patient stayed for observation. Worsening symptoms following protein-losing enteropathy demanded surgical treatment because malignancy could not be ruled out. Laparoscopic resection was performed, and the surgical specimens revealed that the polypoid lesion mainly consisted of mild adenomatous glands which were covered with purulent granulation tissues. We made final diagnosis of cap polyposis and saw rapid improvement of her symptoms. Long-term observation is required after surgery. CONCLUSIONS: We reported a case of successful laparoscopic resection of cap polyposis with protein-losing enteropathy (170 words).

Ciliary and rhabdomeric photoreceptor-cell circuits form a spectral depth gauge in marine zooplankton.

Ciliary and rhabdomeric photoreceptor cells represent two main lines of photoreceptor-cell evolution in animals. The two cell types coexist in some animals, however how these cells functionally integrate is unknown. We used connectomics to map synaptic paths between ciliary and rhabdomeric photoreceptors in the planktonic larva of the annelid Platynereis and found that ciliary photoreceptors are presynaptic to the rhabdomeric circuit. The behaviors mediated by the ciliary and rhabdomeric cells also interact hierarchically. The ciliary photoreceptors are UV-sensitive and mediate downward swimming in non-directional UV light, a behavior absent in ciliary-opsin knockout larvae. UV avoidance overrides positive phototaxis mediated by the rhabdomeric eyes such that vertical swimming direction is determined by the ratio of blue/UV light. Since this ratio increases with depth, Platynereis larvae may use it as a depth gauge during vertical migration. Our results revealed a functional integration of ciliary and rhabdomeric photoreceptor cells in a zooplankton larva.

Pelvic Drain After Laparoscopic Low Anterior Resection for Rectal Cancer in Patients With Diverting Stoma.

BACKGROUND: This study is intended to assess whether the use of pelvic drain reduces incidence of pelvic sepsis in the era of laparoscopic low anterior resection (LAR). PATIENTS AND METHODS: In total, 200 of consecutive patients who underwent laparoscopic LAR for rectal cancer with diverting stoma were analyzed. RESULTS: Pelvic sepsis occurred in 14 of 110 patients (12.7%) in the drain group and in 9 of 90 patients (10.0%) in the no drain group (P=0.548). Furthermore, there were no differences in the incidence of anastomotic leakage, time to diagnosis of pelvic sepsis, and type of treatments for pelvic sepsis. CONCLUSIONS: Prophylactic pelvic drain use after laparoscopic LAR in patients with diverting stoma does not reduce incidence of pelvic sepsis. Routine use of pelvic drain is not recommended. This study was registered at UMIN (Registration Number: UMIN000026076).

Using indocyanine green fluorescent imaging to successfully resect metachronous regional lymph node recurrence of rectosigmoid cancer.

A 39-year-old female patient underwent anterior resection with locoregional lymph node dissection for rectosigmoid cancer at another hospital. The procedure involved transection of the superior rectal artery just below the origin of the left colic artery. Postoperative diagnosis was stage III B. The patient received adjuvant chemotherapy with oxaliplatin plus capecitabine for 6 months. Sixteen months after the operation, PET-CT scans revealed regional lymph node metastases around the root of the inferior mesenteric artery. The patient was referred to our hospital with a recurrence of rectosigmoid cancer. We performed laparoscopic lymph node dissection with real-time indocyanine green fluorescent images superimposed on color images to prevent intraoperative vascular insufficiency. We were able to successfully observe the sufficient blood flow in the descending colon. Postoperative pathological findings showed lymph node recurrence after initial surgery. She was discharged 7 days after the operation. In the 8 months since the second operation, the patient has not had any indication of further recurrence.

CEACAM1 is associated with recurrence after hepatectomy for colorectal liver metastasis.

BACKGROUND: Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is re-expressed at the invasion front of colorectal cancer. CEACAM1 expression at metastatic sites remains to be investigated. The current study aims to clarify the association between CEACAM1 expression and recurrence after hepatectomy of colorectal liver metastasis and to address whether CEACAM1 induces tumor-initiating properties needed for growth at metastatic sites. METHODS: Immunohistochemical analyses for CEACAM1 were performed in 67 patients with liver metastasis of colorectal cancer who had undergone curative hepatectomy. The risk factors for postoperative recurrence were calculated based on a CEACAM1 cytoplasmic domain isoform at the primary tumor invasion front. To investigate the effects of CEACAM1 cytoplasmic isoforms on HT29 and HCT116 colorectal cancer cells, Western blotting for CD44 and CD133, flow cytometry for ALDH1 activity, and soft-agar colony formation assay were performed. RESULTS: CEACAM1 long (CEACAM1-L) and short (CEACAM1-S) cytoplasmic domain isoforms are strongly expressed on cancer cells in the liver metastases. Enhanced CEACAM1-S expression in the state of CEACAM1-L dominance at the primary tumor invasion front was an independent factor for colorectal cancer recurrence after curative hepatectomy. CEACAM1-4S-transfected HT29 and HCT116 cells had significantly higher CD44 expression and ALDH1 activity and increased the growth in anchorage-independent condition. CONCLUSIONS: High expression of CEACAM1-S at the primary lesion invasion front is associated with recurrence and prognosis of patients with colorectal liver metastasis after curative hepatectomy. The expression of CEACAM1-4S enhances the tumor-initiating property of colorectal cancer cells.