Shungo Endo

PET/CT Colonography for the Preoperative Evaluation of the Colon Proximal to the Obstructive Colorectal Cancer

PurposeThis study was designed to evaluate the usefulness of 18-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) colonography in preoperative diagnosis of the tumors proximal to obstructive colorectal cancers, which were defined as cancers that cannot be traversed colonoscopically.MethodsA whole-body PET/CT protocol for tumor staging and a protocol for CT colonography were integrated into one examination. No cathartic bowel preparation was used before this examination. Thirteen prospective patients with obstructive cancer were examined. We compared the detection rates for obstructive colorectal cancers and tumors proximal to the obstruction using air-inflated PET/CT colonography to intraoperative examinations, histopathologic outcome, and follow-up colonoscopy.ResultsPET/CT colonography correctly identified all 13 primary obstructive colorectal cancers and all 2 synchronous colon cancers proximal to the obstruction. The two synchronous colon cancers detected at PET/CT colonography were confirmed and removed at single-stage surgical procedures. PET/CT colonography was able to localize all colorectal cancers precisely. There were no false-negative or false-positive proximal colorectal cancers by PET/CT colonography. Other preoperative examinations missed the synchronous colon cancers.ConclusionsIn patients with obstructive colorectal cancers, preoperative PET/CT colonography provided valuable anatomic and functional information of the entire colon to properly address surgery of colorectal cancer.

Polyethylene glycol solution (PEG) plus contrast medium vs PEG alone preparation for CT colonography and conventional colonoscopy in preoperative colorectal cancer staging

PurposeThis study evaluated the usefulness of combined polyethylene glycol solution plus contrast medium bowel preparation (PEG-C preparation) followed by dual-contrast computed tomography enema (DCCTE) and conventional colonoscopy. The main purpose of these examinations is the preoperative staging of already known tumors.Materials and methodsOne hundred patients with colorectal tumors were alternately allocated to either a polyethylene glycol solution preparation (PEG preparation) group (n=50) or a PEG-C preparation group (n=50) before undergoing conventional colonoscopy and computed tomographic (CT) colonography. After conventional colonoscopy, multidetector row CT scans were performed. Air images were reconstructed for both groups; contrast medium images were additionally reconstructed for the PEG-C preparation group. DCCTE images were a composite of air images and contrast medium images without use of dedicated electronic cleansing software. Quality scores (the presence or absence of blind spots of the colon) were compared between the two groups.ResultsComplete tumor images were obtained by DCCTE for all 50 (100%) lesions in the PEG-C preparation group, as compared with only nine of the 50 lesions (18%) in the PEG preparation group (air-contrast CT enema). The overall quality score in the PEG-C preparation group was significantly better than that in the PEG preparation group (P<0.0001).ConclusionsDCCTE showed the entire colon without blind spots in nearly all patients in the PEG-C preparation group because the areas under residual fluid were reconstructed as contrast medium images. DCCTE and conventional colonoscopy after PEG-C preparation are feasible and safe procedures that can be used for preoperative evaluation in patients with colorectal cancer.

Intraoperative fluoroscopy vs. intraoperative laparoscopic ultrasonography for early colorectal cancer localization in laparoscopic surgery

BackgroundIn colorectal cancer (CRC) surgery, precise tumor localization is important for oncologically correct surgery and adequate tumor and lymph node resection margins. During laparoscopic surgery it is difficult to localize early CRC. The aim of this study was to compare the usefulness of two tumor localization techniques; intraoperative fluoroscopy and intraoperative laparoscopic ultrasonography.MethodsSeventeen patients with CRC necessitating preoperative marking were alternately allocated to either the fluoroscopy (F) group (n = 8) or the laparoscopic ultrasonography (LU) group (n = 9). A three-step technique was used. At first lesions were localized preoperatively by metallic clips that were colonoscopically applied proximally and distally to the tumor site. Second, computed tomography (CT) colonography was taken to obtain preoperative staging. The location of the metallic clips was confirmed by CT colonography, preoperatively. Third, in the F group, intraoperative fluoroscopy was performed to localize the applied clips. In the LU group, the applied clips were detected from the serosal aspect of the colon using intraoperative laparoscopic ultrasonography.ResultsIn all patients, colonoscopic metallic clips were successfully applied and preoperative CT colonography correctly detected the location of the tumor. Marking sites were detected precisely using intraoperative fluoroscopy or intraoperative laparoscopic ultrasonography in all cases, without complications. The mean detection time was 15.8 minutes in the F group and 7.0 minutes in the LU group (p = 0.005). In the LU group, two cases were technically difficult because of interruption of the ultrasound by intestinal air.ConclusionsBoth intraoperative fluoroscopy and intraoperative laparoscopic ultrasonography are safe and accurate techniques for intraoperative localization of early CRC. With regard to detection time, intraoperative laparoscopic ultrasonography is superior to intraoperative fluoroscopy. However, when there is a massive amount of intestinal air, intraoperative laparoscopic ultrasonography is cumbersome in localizing the lesion. Computed tomography colonography is useful for preoperative tumor localization and might be effective for shortening detection time during surgery.

Laparoscopic surgery for colorectal cancer is safe and has survival outcomes similar to those of open surgery in elderly patients with a poor performance status: subanalysis of a large multicenter case–control study in Japan

BackgroundIt remains controversial whether open or laparoscopic surgery should be indicated for elderly patients with colorectal cancer and a poor performance status.MethodsIn those patients aged 80xa0years or older with Eastern Cooperative Oncology Group performance status score of 2 or greater who received elective surgery for stage 0 to stage III colorectal adenocarcinoma and had no concomitant malignancies and who were enrolled in a multicenter case–control study entitled “Retrospective study of laparoscopic colorectal surgery for elderly patients” that was conducted in Japan between 2003 and 2007, background characteristics and short-term and long-term outcomes for open surgery and laparoscopic surgery were compared.ResultsOf the 398 patients included, 295 underwent open surgery and 103 underwent laparoscopic surgery. There were no significant differences in the baseline characteristics between open surgery and laparoscopic surgery patients, except for previous abdominal surgery and TNM stage. The median operation duration was shorter with open surgery (open surgery, 153xa0min; laparoscopic surgery, 202xa0min; Pxa0<xa00.001), and less blood loss occurred with laparoscopic surgery (median open surgery, 109xa0g; median laparoscopic surgery, 30xa0g; Pxa0<xa00.001). An operation duration of 180xa0min or more (odds ratio, 1.97; 95u2009% confidence interval, 1.17–3.37; Pu2009=u20090.011) and selection of laparoscopic surgery (odds ratio, 0.41; 95u2009% confidence interval, 0.22–0.75;xa0Pu2009=u20090.003) were statistically significant in the multivariate analysis for postoperative morbidity. Moreover, laparoscopic surgery did not result in an inferior overall survival rate compared with open surgery (log-rank test Pxa0=xa00.289, 0.278, 0.346, 0.199, for all-stage, stage 0–I, stage II, and stage III disease, respectively).ConclusionsLaparoscopic surgery in elderly colorectal cancer patients with a poor performance status is safe and not inferior to open surgery in terms of overall survival.

Natural Killer-Like T Cell Lymphoma of the Small Intestine : Report of a Case

We report the case of a 77-year-old Japanese man with natural killer (NK)-like T cell lymphoma of the small intestine diagnosed after an emergency laparotomy for perforated peritonitis. Immunohistochemical staining of the tumor showed that the patient had CD3+ CD8+ CD30− CD56+ CD68− CD79a− UCHL-1+ EMA− LMP-1 NK-like T cell lymphoma. The patient had a history of hepatocellular carcinoma (HCC) and was also diagnosed with T cell non-Hodgkins lymphoma associated with T cell receptor (TCR) reconstruction in the Jγ chain. Intestinal T cell lymphoma is uncommon and very few cases of CD56+ T cell lymphoma, otherwise known as NK-like T cell lymphoma, have been reported. The patient did not have a history of gluten-sensitive enteropathy (celiac disease). Multiple lesions appeared within months after the initial operation and his condition deteriorated rapidly. We think that this patient probably had NK-type granular lymphocyte-proliferative disorder (NK-GLPD) because the percentage of CD16+ CD56+ cells among peripheral blood mononuclear cells was elevated, at 21%. We report this case to help elucidate the relationship between underlying digestive organ disease and the development of intestinal NK-like T cell lymphoma. An accumulation of other such cases is needed to determine the etiology of this disease.

Double colorectal cancer only diagnosed by computed tomographic colonography.

A 58-year-old woman presented to her physician with rectal bleeding and intermittent diarrhea. Optical colonoscopy revealed a bulky tumor which was diagnosed as rectal cancer. She was referred to our institution for further evaluation and treatment. Slim optical colonoscopy showed an obstructive cancer in the rectosigmoid junction and no information of the proximal side of the obstruction. The patient then underwent computed tomographic (CT) colonography for further evaluation of the proximal side. Three-dimensional endoluminal ‘fly-through’ images revealed another protruded lesion in the proximal side of the obstruction. Diagnosis of synchronous double cancer was made by CT colonography. This CT data was not only used to create three-dimensional images but also to decide on a preoperative clinical staging. Laparoscopy-assisted high anterior resection was performed and T3 rectal cancer and T1 sigmoid colon cancer were confirmed in the resected specimen. Follow-up optical colonoscopy revealed no other tumors. CT colonography has recently become a popular preoperative examination tool with significant improvement in quality of image due to a rapid progress in computer technology. CT colonography correctly showed synchronous double cancer in our case and provided crucial information for planning surgery. We recommend that CT colonography should be used for evaluating the proximal side of obstructive colorectal cancer.

Positive detection of exfoliated colon cancer cells on linear stapler cartridges was associated with depth of tumor invasion and preoperative bowel preparation in colon cancer

BackgroundThe aim of this study was to investigate exfoliated cancer cells (ECCs) on linear stapler cartridges used for anastomotic sites in colon cancer.MethodsWe prospectively analyzed ECCs on linear stapler cartridges used for anastomosis in 100 colon cancer patients who underwent colectomy. Having completed the functional end-to-end anastomosis, the linear stapler cartridges were irrigated with saline, which was collected for cytological examination and cytological diagnoses were made by board-certified pathologists based on Papanicolaou staining.ResultsThe detection rate of ECCs on the linear stapler cartridges was 20xa0%. Positive detection of ECCs was significantly associated with depth of tumor invasion (pu2009=u20090.012) and preoperative bowel preparation (pu2009=u20090.003). There were no marked differences between ECC-positive and ECC-negative groups in terms of the operation methods, tumor location, histopathological classification, and surgical margins.ConclusionsSince ECCs were identified on the cartridge of the linear stapler used for anastomosis, preoperative mechanical bowel preparation using polyethylene glycol solution and cleansing at anastomotic sites using tumoricidal agents before anastomosis may be necessary to decrease ECCs in advanced colon cancer.

Malignant peritoneal mesothelioma with lymph node metastasis that originated in the transverse colon

BackgroundWe report an extremely rare case of resection of localized biphasic malignant peritoneal mesothelioma of the transverse colon.Case reportComputed tomography and magnetic resonance imaging in a 72-year-old man showed a tumor with enhanced borders consistent with the transverse colon. Colonoscopy showed ulcerative lesions in the transverse colon, but histological examination showed no malignancy. A gastrointestinal stromal tumor was strongly suspected, so an extended right hemicolectomy was performed. Histopathological examination showed that the tumor was a localized malignant peritoneal mesothelioma of the transverse colon. The patient did not receive postoperative chemotherapy and died 18xa0months after surgery.ConclusionsThe number of patients with malignant mesotheliomas is predicted to increase in the future both in Japan and in western countries. We report this case due to its probable usefulness in future studies pertaining to the diagnosis and treatment of malignant mesotheliomas.

Complete laparoscopic surgery for early colorectal cancer after endoscopic resection

Laparoscopic‐assisted colorectal surgery requires a mini‐laparotomy to extract the specimen and insert the anvil head of the circular stapler into the proximal colon. However, such a mini‐laparotomy occasionally causes local pain and surgical‐site infection. To avoid mini‐laparotomy, we invented a new laparoscopic technique, complete laparoscopic surgery for colorectal cancer.

Short- and long-term outcomes following laparoscopic palliative resection for patients with incurable, asymptomatic stage IV colorectal cancer: A multicenter study in Japan

Objective: This retrospective multicenter study compared short- and long-term results between Japanese patients with asymptomatic stage IV colorectal cancer who underwent palliative laparoscopic surgery (LS) versus those who underwent conventional open surgery (OS). Methods: Among 968 patients treated for stage IV colorectal cancer from January 2006 to December 2007 in 41 surgical units that were participating in the Japan Society of Laparoscopic Colorectal Surgery group, we studied 398 patients who received palliative resection of their asymptomatic primary colorectal tumor. Results: We analyzed data from patients undergoing LS (LS group, n=106) and OS (OS group, n=292). Fourteen (13.2%) LS group patients were converted to OS. Although the differences between groups for postoperative complications were not significant, the mean time to solid food intake and postoperative length of hospital stay for the LS group were significantly shorter than those for the OS group (2 vs. 3 days, p<0.0001; 13 vs. 16 days, p<0.0001, respectively). The LS group patients experienced a longer median survival time than that of the OS group (24.5 vs. 23.9 months, p=0.0357). Conclusions: Laparoscopic palliative resection (LS) offers advantages for short-term outcomes and no disadvantages for long-term outcomes. The use of laparoscopic procedures to treat asymptomatic, incurable stage IV colorectal cancer appears to be acceptable.