Prediction of colorectal tumor grade and invasion depth through narrow-band imaging scoring.

AIM: To determine the usefulness of assigning narrow-band imaging (NBI) scores for predicting tumor grade and invasion depth in colorectal tumors. METHODS: A total of 161 colorectal lesions were analyzed from 138 patients who underwent endoscopic or surgical resection after conventional colonoscopy and magnifying endoscopy with NBI. The relationships between the surface and vascular patterns of the lesions, as visualized with NBI, and the tumor grade and depth of submucosa (SM) invasion were determined histopathologically. Scores were assigned to distinct features of the surface microstructures of tubular and papillary-type lesions. Using a multivariate analysis, a model was developed for predicting the tumor grade and depth of invasion based on NBI-finding scores. RESULTS: NBI findings that correlated with a high tumor grade were associated with the "regular/irregular" (P < 0.0001) surface patterns and the "avascular area" pattern (P = 0.0600). The vascular patterns of "disrupted vessels" (P = 0.0714) and "thick vessels" (P = 0.0133) but none of the surface patterns were associated with a depth of invasion of ≥ 1000 µm. In our model, a total NBI-finding score ≥ 1 was indicative of a high tumor grade (sensitivity: 0.97; specificity: 0.24), and a total NBI-finding score ≥ 9 (sensitivity: 0.56; specificity: 1.0) was predictive of a SM invasion depth ≥ 1000 µm. Scores less than these cutoff values signified adenomas and a SM invasion depth < 1000 µm, respectively. Associations were also noted between selected NBI findings and tumor tissue architecture and histopathology. CONCLUSION: Our multivariate statistical model for predicting tumor grades and invasion depths from NBI-finding scores may help standardize the diagnosis of colorectal lesions and inform therapeutic strategies.

Endoscopic analysis of colorectal serrated lesions with cancer.

Serrated lesions, including hyperplastic polyps (HPs), traditional serrated adenomas (TSAs) and sessile serrated adenomas/polyps (SSA/Ps), are important contributors to colorectal carcinogenesis. The aim of the present study was to analyze the potential of conventional endoscopy and advanced endoscopic imaging techniques to delineate the characteristic features of serrated lesions with cancer. The present study was a retrospective analysis of the data of 168 patients who had undergone colonoscopy, and a total of 228 serrated lesions (77 HPs, 58 TSAs, 84 SSA/Ps, 9 SSA/P plus TSAs) have been identified in these patients. A cancer component was identified in 2.6% of HPs, 13.8% of TSAs and 10.7% of SSA/Ps, but none of SSA/P plus TSAs. Compared with the lesions without cancer, the lesions with cancer exhibited a larger size (HP, TSA and SSA/P), a reddish appearance (SSA/P), a two-tier raised appearance (HP and SSA/P), a central depression (HP, TSA and SSA/P), the type V pit pattern (HP, TSA and SSA/P), and/or the type III capillary pattern (TSA and SSA/P). Deep invasion was identified in 50.0% of HPs, 12.5% of TSAs and 55.6% of SSA/Ps with cancer. The Ki-67 proliferative zone was distributed diffusely within the area of the cancer, but partially within the non-cancer area of HPs, TSAs and SSA/Ps. The lesion types were also analyzed on the basis of mucin phenotype. The present study suggested that a detailed endoscopic analysis of serrated lesions with cancer is useful for delineating characteristic features, and the analysis aids treatment selection.

Molecular biological characteristics, diagnosis and treatment of the colorectal serrated lesions.

Previous data shows that colorectal serrated lesions are precursor of carcinogenesis. It has been advancing even molecular biological analysis, SSA/P become microsatellite instability (MSI) positive colon cancers and TSA become microsatellite stable (MSS) positive colon cancers. It is observed that redness and double elevation in conventional endoscopy, CP type II (Sano classification) in the NBI endoscopy, type III pit pattern in magnifying endoscopy, if SSA/P have cytological dysplastic change. Especially, if SSA/P have cancerous change, CP type III and type V pit pattern are observed.

Quantitative analysis of colorectal mucosal lesions by autofluorescence endoscopy: discrimination of carcinomas from other lesions.

A newly developed autofluorescence (AF) imaging technique was applied during colonoscopy in a clinical setting. This pilot study was conducted to evaluate the clinical feasibility of applying AF endoscopy for distinguishing colorectal lesions. A total of 54 colorectal mucosal lesions obtained from 43 patients who underwent both white-light and AF endoscopy and were treated by endoscopy or surgery were assessed. Of the lesions, 11 were hyperplastic polyps, 30 were adenomas and 13 were carcinomas. To quantify the AF intensity, a color-contrast index (CCI) was determined and evaluated in relation to the histology, size and shape of each lesion. CCI was significantly associated with the histology and size of the lesions, but not their shape. CCI increased as the malignant potential increased (in the order of hyperplastic polyps→adenomas→carcinomas), irrespective of the lesion size (r=0.797, p<0.0001 for size>8 mm; r=0.622, p=0.0045 for size>8 mm but >15 mm; r=0.644, p=0.0071 for size>15 mm). In each size group, CCI tended to be higher for carcinomas than for adenomas, and also higher for adenomas than for hyperplastic polyps. CCI allowed discrimination of adenomas/carcinomas from hyperplastic polyps with 95.3% sensitivity and 63.6% specificity (cut-off value, 14.5), and of colorectal carcinomas from adenomas with 84.6% sensitivity and 80.0% specificity (cut-off value, 28.0). These results suggest that the quantitative analysis of AF intensity using CCI is helpful to discriminate among different types of colorectal mucosal lesions, including carcinomas.

Endoscopic discrimination of sessile serrated adenomas from other serrated lesions.

Sessile serrated adenoma (SSA) is a proposed precursor of colorectal carcinogenesis. This study aimed to analyze the potential of endoscopy to discriminate SSA from other serrated lesions, specifically traditional serrated adenoma (TSA) and hyperplastic polyp (HP). Of 145 serrated lesions, 111 sessile serrated lesions including 32 TSAs, 25 SSAs and 54 HPs were analyzed for size, color, location and morphologic features using conventional endoscopy and magnifying chromoendoscopy. SSA was preferentially located in the right colon, whereas TSA and HP were located in the left colon. The sizes of SSA and TSA were larger than those of HP. The lesion color was indistinguishable among TSA, SSA and HP. Macroscopically, a pinecone-like or two-tier raised appearance were found more frequently in TSA than in SAA and HP. Under magnified chromoendoscopic observation, the stellar III(L) pit pattern and fern-like appearance were observed more frequently in TSA than in SAA and HP. In conclusion, endoscopic discrimination between SSA and other sessile serrated lesions based on morphological features was difficult. However, size and location of the lesions facilitated diagnosis.

[Case of overwhelming postsplenectomy infection (OPSI) with chronic hepatitis type C during peginterferon/ribavirin combination therapy].

A 61-year-old woman with a past history of splenectomy was admitted to our hospital because of high fever and loss of consciousness during interferon therapy for the treatment of chronic hepatitis type C. She died of multiple organ failure, and disseminated intravascular coagulation shortly after admission. The results of blood culture and the autopsy revealed sepsis due to streptcoccus pneumonia. The neutropenia and immunosuppression by interferon therapy induced overwhelming postsplenectomy infection (OPSI), a potentially rapidly fatal septicemia. When we perform treatment with immunosuppression such as interferon therapy or anticancer drug therapy to splenectomised patients, it is necessary to carry out pnemococcus vaccination. Splenectomy is performed for patients with thrombocytopenia of chronic hepatitis type C before interferon therapy. To avoid OPSI, partial splenic arterial embolization was discussed.