Yutaka Orii

Invasion depth diagnosis of depressed type early colorectal cancers by combined use of videoendoscopy and chromoendoscopy

BACKGROUND Depressed type early colorectal cancers are found less frequently than other polypoid cancers although they have a higher submucosal invasion rate. Recently videocolonoscopy and chromoendoscopy have become available and precise descriptions of these lesions are now routine. Because endoscopic mucosal resection is designated for intramucosal and focally extended submucosal (m-sm1) cancers, an evaluation of the characteristic findings indicating invasion depth with these modalities is important. METHODS Between January 1991 and March 1996, 64 depressed type early colorectal cancers were detected and treated. When a faint abnormality of the mucosa was suspected by routine videocolonoscopy, 0.1% of indigo carmine solution was sprayed on the mucosal surface (chromoendoscopy). Colonoscopic findings of m-sm1 cancers and moderately and massively extended submucosal (sm2-3) cancers were retrospectively reviewed and compared with confirmed histologic findings. RESULTS Characteristic colonoscopic findings needed for surgical operation were as follows: (1) expansion appearance, (2) deep depression surface, (3) irregular bottom of depression surface, and (4) folds converging toward the tumor. By using these findings, the invasion depth of depressed type early colorectal cancers could be correctly determined in 58 of 64 lesions (91%). CONCLUSIONS Characteristic colonoscopic findings obtained by a combination of videocolonoscopy and chromoendoscopy are useful for determination of the invasion depth of depressed type colorectal cancers, an essential factor in choosing a treatment modality.

Natural history of colorectal nonpolypoid adenomas: a prospective colonoscopic study and relation with cell kinetics and K- ras mutations

OBJECTIVE:Serial colonoscopic observations were prospectively conducted to elucidate the natural history of nonpolypoid tumors. Furthermore, to clarify whether cell kinetic status affects the tumor development, proliferative indices, apoptotic indices, and K-ras codon 12 point mutations on biopsy specimens were investigated.METHODS:Seventy-five colorectal tumors, 13 polypoid and 62 nonpolypoid type (56 flat elevated and six depressed type) were studied. Proliferating and apoptotic cells were detected with anti-Ki-67 antibody and the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling method, respectively. Point mutations at K-ras codon 12 were examined by enriched polymerase chain reaction-based restriction fragment length polymorphism assay.RESULTS:The average follow-up period was 22 months (range 1–50). The lesions of subsequent exophytic growth, unchanged shape, depressed growth, and disappearance were observed in 0%, 92%, 0%, and 8% of polypoid type, in 39%, 39%, 13%, and 9% of flat elevated type, and in 33%, 67%, 0%, and 0% of depressed type, respectively. There was no significant difference in tumor size between initial and follow-up colonoscopy. Nonpolypoid tumors apparently changed to the exophytic growth during 2 yr or more. The tumors with exophytic growth had significantly higher proliferative indices/apoptotic indices ratios than those with unchanged morphology and disappearance/depressed growth (p < 0.05, respectively). K-ras codon 12 point mutations did not correlate with tumor development.CONCLUSIONS:Cell kinetic status plays an important role in determining minute colorectal tumor development, but not K-ras codon 12 mutations. Minute nonpolypoid adenomas frequently tend to grow slowly, and nearly 40% of those become the exophytic growth with time. Most of minute nonpolypoid tumors seem to follow the adenoma-carcinoma sequence.

C ASE R EPORT: Mucinous cholangiocarcinoma featuring a multicystic appearance and periportal collar in imaging

A case of mucinous cholangiocarcinoma (CC), a rare histological type of CC, featuring unusual images is reported. The patient was hospitalized because of acute development of jaundice and fever. Computed tomography demonstrated multiple cystic lesions in the liver and a band‐like low density area parallel to the intrahepatic portal vein, a so‐called ‘periportal collar’. Endoscopic cholangiography revealed a stricture of the hepatic duct with slight upstream dilatation. Cytology of the bile juice and fine‐needle aspiration of the cystic lesion in the liver disclosed mucinous carcinoma. The patient died of multiorgan failure 3 weeks after admission. The autopsied liver showed that multiple mucus lakes were lined with adenocarcinoma cells and signet ring cells were floating in the mucus lakes. The cancer cells had spread along the portal tract and invaded into the hepatic parenchyma.

Selective Endoscopic Retrograde Pancreatography (Selective ERP) Using a Radifocus Gllidewire–A New Technique for a Diagnostic Pancreatogram

Abstract: We have developed a new method called the “Selective Endoscopic Retrograde Pancreatograpy (Selective ERP)” which uses a Radifocus guidewire to obtain a more precise pancreatogram than a standard ERP. The deep cannulation of a catheter guided by a Radifocus guidewire following standard ERP was easily and rapidly accomplished and precise pancreatograms were successfully obtained. The Selective ERP was very useful not only for obtaining detailed pancreatograms beyond severe stenosis of the main pancreatic duct in ductal cell carcinoma of the pancreas but also in revealing whether mucinous cystadenoma/cystadenocarcinoma communicated with the pancreatic duct or not. In the case of a mucin producing pancreatic tumor, Selective ERP successfully enabled us to obtain a whole pancreatogram and the location and extent of a tumor that standard ERP often fails to reveal because of an abundant accumulation of mucin in the duct.