Size does not determine the grade of malignancy of early invasive colorectal cancer

AIM:To clarify the clinicopathological characteristics of small and large early invasive colorectal cancers(EI-CRCs),and to determine whether malignancy grade depends on size.METHODS:A total of 583 consecutive EI-CRCs treated by endoscopic mucosal resection or surgery at the National Cancer Center Hospital between 1980 and 2004 were enrolled in this study.Lesions were classified into two groups based on size:small(≤10mm) and large(>10mm).Clinicopathological features,incidence of lymph node metastasis(LNM) and risk factors for LNM,such as depth of invasion,lymphovascular invasion(LVI) and poorly differentiated adenocarcinoma(PDA) were analyzed in all resected specimens.RESULTS:There were 120(21%) small and 463(79%) large lesions.Histopathological analysis of the small lesion group revealed submucosal deep cancer(sm:≥1000 μm) in 90(75%) cases,LVI in 26(22%) cases,and PDA in 12(10%) cases.Similarly,the large lesion group exhibited submucosal deep cancer in 380(82%) cases,LVI in 125(27%) cases,and PDA in 79(17%) cases.The rate of LNM was 11.2% and 12.1% in the small and large lesion groups,respectively.CONCLUSION:Small EI-CRC demonstrated the same aggressiveness and malignant potential as large cancer.

Pathological response measured using virtual microscopic slides for gastric cancer patients who underwent neoadjuvant chemotherapy

BACKGROUND Although pathological response is a common endpoint used to assess the efficacy of neoadjuvant chemotherapy (NAC) for gastric cancer, the problem of a low rate of concordance from evaluations among pathologists remains unresolved. Moreover, there is no globally accepted consensus regarding the optimal evaluation. A previous study based on a clinical trial suggested that pathological response measured using digitally captured virtual microscopic slides predicted patients’ survival well. However, the pathological concordance rate of this approach and its usefulness in clinical practice were unknown. AIM To investigate the prognostic utility of pathological response measured using digital microscopic slides in clinical practice. METHODS We retrospectively evaluated pathological specimens of gastric cancer patients who underwent NAC followed by surgery and achieved R0 resection between March 2009 and May 2015. Residual tumor area and primary tumor beds were measured in one captured image slide, which contained the largest diameter of the resected specimens. We classified patients with < 10% residual tumor relative to the primary tumorous area as responders, and the rest as non-responders;we then compared overall survival (OS) and relapse-free survival (RFS) between these two groups. Next, we compared the prognostic utility of this method using conventional Japanese criteria. RESULTS Fifty-four patients were evaluated. The concordance rate between two evaluators was 96.2%. Median RFS of 25 responders and 29 non-responders was not reached (NR) vs 18.2 mo [hazard ratio (HR)= 0.35, P = 0.023], and median OS was NR vs 40.7 mo (HR = 0.3, P = 0.016), respectively. This prognostic value was statistically significant even after adjustment for age, eastern cooperative oncology group performance status, macroscopic type, reason for NAC, and T- and Nclassification (HR = 0.23, P = 0.018). This result was also observed even in subgroup analyses for different macroscopic types (Borrmann type 4/non-type 4) and histological types (differentiated/undifferentiated). Moreover, the adjusted HR for OS between responders and non-responders was lower in this method than that in the conventional histological evaluation of Japanese Classification of Gastric Carcinoma criteria (0.23 vs 0.39, respectively). CONCLUSION The measurement of pathological response using digitally captured virtual microscopic slides may be useful in clinical practice.

Endoscopic diagnosis of cytomegalovirus gastritis after allogeneic hematopoietic stem cell transplantation

AIM:To clarify the endoscopic and clinical findings of cytomegalovirus(CMV) gastritis after allogeneic hematopoietic stem cell transplantation(allo-SCT).METHODS:Between 1999 and 2005,523 patients underwent allo-SCT at our hospital,and 115 of these patients with gastrointestinal symptoms underwent esophagogastroduodenoscopy.RESULTS:CMV gastritis was diagnosed pathologically in seven patients(1.3%) with the other 108 patients serving as controls.Six of the seven patients developed positive CMV antigenemia,and five complained of abdominal pain.Development of abdominal pain preceded CMV antigenemia in four of the f ive patients.Endoscopic examination showed oozing(n=2),erosion(n=6),and redness(n=5) in the seven patients with CMV gastritis,while the control patients showed oozing(n=3),erosion(n=24),and redness(n=100).Erosion and oozing were more frequently documented in patients with CMV gastritis compared with the controls,and the differences were statistically significant(P=0.0012 and 0.029,respectively).CMV inclusion bodies were documented in 12 of 14 biopsy specimens obtained from erosive lesions,while they were identif ied in 4 of 15 biopsy specimens obtained from lesions other than erosions(P=0.0025).CONCLUSION:This study suggests that erosion and oozing,as well as abdominal pain,are useful indicators in the diagnosis of CMV gastritis following allo-SCT.