Koji Komori

Aichi Cancer Center, Nagoya, Aichi, Japan

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Publications (61)120.16 Total impact

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    ABSTRACT: Background: Laparoscopic surgery is becoming the preferred technique for most colorectal interventions. This study aimed to clarify the time trend of surgical treatment for familial adenomatous polyposis (FAP) and its relevance to clinical outcomes in Japan over a 13-year period. Methods: This was a multicenter retrospective cohort study comprising 23 specialist institutions for colorectal disease and a cohort of 282 FAP patients who underwent total colectomy or proctocolectomy during 2000-2012. Patient clinical backgrounds and surgical outcomes were compared between the first and second halves of the study period. Results: The proportion of surgical types adopted over the entire study period was 46, 21, 30, and 3 % for ileoanal anastomosis (IAA), ileoanal canal anastomosis, ileorectal anastomosis, and permanent ileostomy, respectively. FAP patients undergoing laparoscopic surgery have increased since 2008 and reached 74 % in the past 3 years. In particular, the number of patients undergoing laparoscopic proctocolectomy with IAA increased approximately four-fold from the first to the second half of the study period. A laparoscopic approach was increasingly used in patients with coexisting colorectal malignancies. Despite this trend, surgical results of the laparoscopic approach between the two study periods showed similar morbidity, pouch operation and stoma closure completion rates. No postoperative mortality was observed in this series, and laparoscopic surgery was comparable to open surgery in terms of stoma closure rate, incidence of intra-abdominal/abdominal desmoid tumors, and postoperative survival rate in both study periods. Conclusion: Laparoscopic approach is increasingly being adopted for prophylactic FAP surgery in Japan and may provide clinically acceptable practical outcomes.
    No preview · Article · Jan 2016 · International Journal of Clinical Oncology
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    ABSTRACT: Background: Both bevacizumab and anti-epithelial growth factor receptor (EGFR) agents (e.g. cetuximab and panitumumab) are sequentially used for metastatic colorectal cancer (mCRC). Their co-administration as a first-line treatment does not improve outcome, indicating that there are negative interactions between these agents. A long-term pharmacokinetics study demonstrated serum persistence of bevacizumab following termination of bevacizumab 6 months after the last administration. This prompted us to investigate the impact of short intervals between bevacizumab and anti-EGFR antibody on the efficacy of subsequent anti-EGFR therapy. Methods: We retrospectively reviewed consecutive patients with KRAS exon 2 wild-type mCRC who underwent anti-EGFR therapy after the failure of fluoropyrimidines, oxaliplatin and irinotecan. We divided patients into two groups (Group A: the interval between bevacizumab and anti-EGFR agent< 6 months; Group B: the interval >6 months). Results: Of the 114 included patients (median age, 63 years), 78 (68%) were male. Most patients (88%) were treated with cetuximab plus irinotecan. Groups A and B consisted of 74 and 40 patients, respectively. There were no significant differences in patient characteristics. Group B patients had significantly longer progression-free survival (4.2 vs. 6.6 months; HR, 0.65; 95% CI, 0.43-0.98; P = 0.038) and longer overall survival (11.6 vs. 14.3 months; HR, 0.63; 95% CI, 0.41-0.98, P = 0.039). The response rate was 24.3% in Group A and 47.5% in Group B (P = 0.012). Conclusion: A short interval between bevacizumab and anti-EGFR antibody treatment may interfere with the efficacy of subsequent anti-EGFR therapy.
    No preview · Article · Jan 2016 · Japanese Journal of Clinical Oncology
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    ABSTRACT: Background Conservative treatments are usually attempted for the management of post-esophagectomy chylous leakage. However, surgical intervention may be needed when the chylous leakage cannot be stopped using conservative treatments. For the therapeutic management of refractory chylous leakage, it is important to identify the leakage sites when deciding if surgical intervention is required. Methods Nine patients underwent lymphangiography for the treatment of refractory post-esophagectomy chylous leakage. Radiological findings, the daily outputs of pleural effusion after lymphangiography, and the clinical outcomes after lymphangiography were analyzed in our cases and in a retrospective collection of 24 cases from 1983 to 2015 recorded with precise detail. Results In the 9 cases directly studied in our center, the median postoperative day of lymphangiography was 15 days. The detection rate of leakage sites after lymphangiography was 89 %. After lymphangiography, daily outputs of pleural effusion less than 500 ml were observed in 5 patients (56 %), all of whom healed conservatively. Daily outputs of more than 500 ml were seen in 4 patients (44 %). Of these patients, 1 patient had leakage from the main trunk and underwent clipping of the thoracic duct. In the remaining 3 patients, the leakages were instead observed in branches or were not observed; the 2 patients who had no anatomical variants were healed by chemical pleurodesis, and the 1 patient who had anatomical variants required surgical intervention. In the analysis of 33 previously reported cases (which included our 9 cases), the therapeutic policy was determined after lymphangiography, and all patients were successfully healed. Conclusions Early lymphangiography is recommended for patients with refractory post-esophagectomy chylous leakage. Lymphangiography may contribute valuable information in deciding whether surgical intervention is required.
    No preview · Article · Dec 2015 · Esophagus
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    ABSTRACT: Background: A sufficient surgical margin is critical for preventing re-recurrence and achieving R0 status after resection of a local recurrence of rectal cancer (LRRC). Patients and Methods: Re-recurrence-free survival was analyzed in 110 cases of LRRC according to histological type of primary lesion. The circumferential resection margin (CRM) was classified as 'R1' (x=0 mu m), 'R0 shortness' (0 mu m <x< 2,000 mu m), or 'R0 longness' (x >= 2,000 mu m). The histological change from the primary lesion to the recurrent lesion was classified as 'No change pattern', from well-to moderately-differentiated (W/M) to an expanding lesion; as 'Change pattern', from W/M to an infiltrating lesion. Results: Re-recurrence-free survival was better in 'R0 longness' than 'R0 shortness' groups and showed that 'No change pattern' cases had considerably better prognosis than 'Change pattern' cases. Conclusion: Ensuring a CRM >2,000 mu m during resection of LRRC is more likely to prevent rerecurrence. Cases with poorly differentiated carcinoma from the primary lesion to the recurrent lesion tend to have poor prognoses.
    No preview · Article · Dec 2015 · Anticancer research
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    ABSTRACT: With advances in surgical procedures and perioperative management, hepato-biliary-pancreatic surgery, including hepatectomy and pancreaticoduodenectomy, has been employed for recurrent colon cancer. However, no report has described a case of major hepatectomy with the combined resection of hepaticojejunostomy following pancreaticoduodenectomy for locoregionally recurrent colon cancer. Here, such a case is reported. The patient, a 37-year-old woman, had undergone pancreaticoduodenectomy for lymph node recurrence along the extrahepatic bile duct from cecal cancer. Thirteen months later, a biliary stricture was found at the hepaticojejunostomy site and right hepatectomy was performed. The resected specimen showed a papillary tumor at the hepaticojejunostomy. Based on its histological features, the pathogenesis of this tumor was considered to be intramural recurrence via lymphatic vessels. Although she underwent resection of a lymph node recurrence at her mesentery 12 months later, she has remained well thereafter, without any sign of further recurrence during 5 years of follow-up after hepatectomy.
    Preview · Article · Dec 2015
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    ABSTRACT: Most genome-wide association studies of colorectal cancer (CRC) carried out to date have been in populations with European ancestry, and the extent to which the identified variants contribute as predictors of CRC among Japanese populations has not been clarified. We analyzed 23 genetic variants identified in previous genome-wide association studies in a derivation case-control study with 558 cases and 1116 age-matched and sex-matched controls. Six single nucleotide polymorphisms were selected for synthesis of the genetic risk score. A dose-dependent association was observed between CRC risk and genetic risk score, which is the aggregate number of alleles in six selected variants: 8q24 - rs6983267, 15q13 - rs4779584 and rs1696961, 14q22 - rs444435, 16q22 - rs9929218, and 3q26.2 - rs1093599. The c statistic for a model that included the genetic risk score and conventional risk factors was 0.7167, versus 0.7009 with the conventional risk factors only (P=0.0013). This model was evaluated in a replication study with 547 cases and 547 age-matched and sex-matched controls, and the corresponding c statistics were 0.6356 and 0.6391 with no statistical significance. When the two studies were combined, the corresponding c statistics were 0.6132 and 0.6198 (P=0.0126). We developed a risk model that incorporates a genetic risk score and established risk factors, but this model was not satisfactory in the replication study. The results in the combined study still encourage further attempts using a similar approach among individual countries.
    No preview · Article · Dec 2015 · European Journal of Cancer Prevention
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    ABSTRACT: Background: This observational study was conducted to compare the rate of symptomatic anastomotic leakage (AL), as defined by precise criteria, between laparoscopic and open surgery in patients with mid-to-low rectal cancer using a relatively novel statistical technique. Methods: A total of 1014 consecutive low anterior resection (LAR) patients were registered, of whom 936 were included in this prospective, multicenter, and cohort study (UMIN-CTR, Number 000004017). Patients with rectal cancer within 10 cm from the anal verge underwent either open or laparoscopic LAR at one of the 40 institutions in Japan from June 2010 to February 2013. The primary endpoint of this study was to compare the rate of symptomatic AL between the two groups before and after propensity score matching (PSM). The secondary endpoint was to analyze the risk factors for symptomatic AL in open and laparoscopic surgery. Results: After PSM, the incidence of symptomatic AL in open and laparoscopic surgery was 12.4 and 15.3 %, respectively (p = 0.48). AL requiring relaparotomy occurred after 3.8 % of open surgeries and 6.2 % of laparoscopic surgeries (p = 0.37). Multivariate analysis identified male gender as an independent risk factor for symptomatic AL following laparoscopic surgery (p = 0.001; odds ratio 5.2; 95 % CI 2.0-13.8), and male gender (p = 0.004; odds ratio 2.6; 95 % CI 1.3-5.6), tumor size (p = 0.002; odds ratio 1.2; 95 % CI 0.7-0.9), and number of stapler firing (p = 0.04; odds ratio 4.1; 95 % CI 1.0-15.0) following open surgery. Conclusion: The rate of symptomatic AL was comparable following laparoscopic and open LAR in this large, multicenter, cohort study after PSM. Male gender was associated with an increased risk of symptomatic AL after laparoscopic LAR.
    No preview · Article · Oct 2015 · Surgical Endoscopy
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    ABSTRACT: Rectourethral fistula is one of the complications that can occur after prostatectomy in the urologic discipline. However, a delayed-onset rectourethral fistula after intersphincteric resection (ISR) for low rectal cancer is extremely rare. Here, we report one such case in a 57-year-old man. After ISR for low rectal cancer with a diverting stoma (DS), the DS was closed. After approximately 1 year, frequent pneumaturia and right orchitis were observed. Results of contrast enemas and abdominal computed tomography examinations revealed a rectourethral fistula from an anastomosis to the urethra. The colonoscopic appearance revealed a pinhole fistula on the anastomotic line, with thick pus. We performed a transverse colostomy, and the pneumaturia and right orchitis were no longer observed. Two months later, colonoscopy, contrast enemas, and cystoscopy revealed no rectourethral fistula. To the best of our knowledge, our case is the first report of a delayed-onset rectourethral fistula after ISR.
    Preview · Article · Sep 2015
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    ABSTRACT: We report the case of a 60-year-old male who was diagnosed with gastric cancer. Upper gastrointestinal endoscopy indicated advanced cancer in the posterior wall of the gastric body. Biopsy revealed poorly differentiated adenocarcinoma. Abdominal computed tomography demonstrated thickening of the gastric wall and enlargement of the regional lymph nodes and of the para-aortic lymph nodes (PAN). The involvement of the PAN extended from the celiac axis to the caudal area of the inferior mesenteric artery [cT3N3aH0P0M1(LYM), stage IV]. Systemic chemotherapy was initiated. After 3 courses of S-1 plus cisplatin combination chemotherapy, the primary lesion and the enlarged lymph nodes revealed marked regression except for a minute residual lesion in the lymph nodes. Upon obtaining informed consent, open distal gastrectomy, D2 lymphadenectomy with PAN dissection, and Roux-en-Y reconstruction were performed. The patient was discharged from the hospital 35 days after the operation. Histopathological examination of the resected samples revealed malignant cells only in the PAN, not in the stomach or in the regional lymph nodes [ypT0N0M1(LYM), stage IV]. Currently, the patient is undergoing postoperative adjuvant chemotherapy with S-1 and has remained well without any recurrence after 6 months following surgery.
    Preview · Article · Sep 2015 · Case Reports in Oncology
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    ABSTRACT: The relative risk of cancer recurrence with postoperative adjuvant FOLFOX/CapeOX therapy(Ox)for stage III colorectal cancer is reduced by approximately 20%when compared to that with fluorouracil plus Leucovorin. We performed a questionnaire survey to evaluate the quality of life(QOL)and extent of side effects in patients who received adjuvant chemotherapy. In order to evaluate the risks and benefits of oxaliplatin administration, we also examined the differences in awareness of oxaliplatin side effects between patients and medical staff. Responses were obtained from 147 patients, 54 doctors, and 84 nurses. Analysis of the patient responses showed higher current QOL scores regardless of the chemotherapy regimen, although patients in the Ox group had a high rate of residual sensory peripheral neuropathy. In the Ox group, 81% of patients responded that the side effects were moderate. In contrast, 40% of medical staff identified the side effects of oxaliplatin as severe, which differed from that reported by the patients. Considering that Ox adjuvant chemotherapy may reduce the risk of recurrence by approximately 20%, the risk/benefit balance is acceptable.
    No preview · Article · Apr 2015 · Gan to kagaku ryoho. Cancer & chemotherapy
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    ABSTRACT: Fournier's gangrene is a rapidly progressing necrotizing fasciitis of the perineum and external genital organs. The disease is life-threatening and has a high mortality rate. Therefore, prompt diagnosis and treatment is needed. The present case was a 61-year-old man who complained of gluteal pain. The gluteal region and scrotum were swollen and partially necrotized, and a whole-circumference tumor was palpable on digital examination of the rectum. CT scans revealed rectal wall thickening, widespread gas filling the area from the gluteal region to the scrotum, and extravasation of contrast media from the stomach. We diagnosed Fournier's gangrene caused by penetration of rectal cancer and upper gastrointestinal bleeding. For treatment, we first tried endoscopic hemostasis, but this proved troublesome because of the limited working area caused by a clot. We then used laparotomy to perform gastrectomy, transverse colostomy, and debridement of the perineal area. Here, we report this case, along with a review of the literature.
    Preview · Article · Jan 2015 · Nippon Shokaki Geka Gakkai zasshi
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    ABSTRACT: Restorative proctocolectomy with the formation of an ileal pouch-anal anastomosis has become the most common surgical option for patients with familial adenomatous polyposis (FAP). However, adenomas may develop in the ileal pouch mucosa over time, and even carcinoma in the pouch has been reported. We therefore reviewed the prevalence, nature, and treatment of adenomas and carcinoma that develop after proctocolectomy in the ileal pouch mucosa in patients with FAP. In 36 reports that were reviewed, the incidence of adenomas in the ileal pouch varied from 6.7% to 73.9%. The risk appears to be 7% to 16% after 5 years, 35% to 42% after 10 years, and 75% after 15 years. On the other hand, only 22 cases of ileal pouch carcinoma have been recorded in the literature to date. The diagnosis of pouch carcinoma was made between 3 to 23.6 years (median, 10 years) after pouch construction. Although the risk of malignant transformation in ileal pouches is probably low, it is not negligible, and the long-term risk cannot be well quantified at present. Regular endoscopic surveillance, especially under optimal bowel preparation and using chromoendoscopy, are recommended.
    Preview · Article · Jan 2015 · Nippon Daicho Komonbyo Gakkai Zasshi
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    ABSTRACT: Thoracic esophageal cancer with a double aortic arch is extremely rare. We herein report the case of a 63-year-old man with a double aortic arch who underwent an esophagectomy with a three-field lymphadenectomy for cancer in the lower thoracic esophagus. In such cases, it is important to recognize the relationship between the right and left aortic arches and the bilateral recurrent laryngeal nerves (RLNs). We were able to accurately understand the anatomical position of the RLNs using a precedent cervical procedure with partial resection of the manubrium to remove the nodes along the bilateral RLNs.
    No preview · Article · Dec 2014 · General Thoracic and Cardiovascular Surgery
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    ABSTRACT: Adding oxaliplatin to fluorouracil-based chemotherapy can improve the survival of patients with stage III colorectal cancer by approximately 20 %. Reportedly, cancer patients are much more likely to prefer chemotherapy than medical professionals, although there is only a very small chance of achieving benefits from treatment. However, chronic neurotoxicity may be long lasting after the administration of oxaliplatin-based chemotherapy. This study aimed to evaluate potential side effects and differences in attitude between colorectal cancer patients and medical staff regarding the risk-benefit trade-offs of chemotherapy. Relapse-free colorectal cancer patients who received adjuvant chemotherapy, doctors, and nurses were surveyed using a questionnaire regarding the side effects of chemotherapy and hypothetical clinical scenarios to quantify gains in the risk of relapse that were deemed necessary to make chemotherapy worthwhile. Responses were obtained from 147 patients, 54 doctors, and 84 nurses. Of these, 39 % of patients and 85 % of doctors replied that moderate side effects of adjuvant chemotherapy were worthwhile to achieve an absolute gain in the risk of relapse of 10 % from a baseline of 40 %. More severe side effects, as reported by colorectal cancer patients, were not associated with the larger gains necessary to make treatment worthwhile. Seven percent of patients treated with oxaliplatin, 40 % of doctors, and 43 % of nurses replied that side effects associated with oxaliplatin-based chemotherapy were severe. Doctors should consider potential heterogeneity in side effects and attitudes regarding the risk-benefit balance of adjuvant chemotherapy, and that patient perspectives should enhance shared decision-making.
    No preview · Article · Nov 2014 · International Journal of Clinical Oncology

  • No preview · Article · Nov 2014 · Nippon Shokakibyo Gakkai zasshi The Japanese journal of gastro-enterology
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    ABSTRACT: Abstract This study aimed to assess the pathogenic causes, clinical conditions, surgical procedures, in-hospital mortality, and operative death associated with emergency operations at a high-volume cancer center. Although many reports have described the contents, operative procedures, and prognosis of elective surgeries in high-volume cancer centers, emergency operations have not been studied in sufficient detail. We retrospectively enrolled 28 consecutive patients who underwent emergency surgery. Cases involving operative complications were excluded. The following surgical procedures were performed during emergency operations: closure in 3 cases (10.7%), diversion in 22 cases (78.6%), ileus treatment in 2 cases (7.1%), and hemostasis in 1 case (3.6%). Closure alone was performed only once for peritonitis. Diversion was performed in 17 cases (77.3%) of peritonitis, 4 cases (18.2%) of stenosis of the gastrointestinal tract, and 1 case (4.5%) of bleeding. There was a significant overall difference (P = 0.001). The frequency of emergency operations was very low at a high-volume cancer center. However, the recent shift in treatment approaches toward nonoperative techniques may enhance the status of emergency surgical procedures. The results presented in this study will help prepare for emergency situations and resolve them as quickly and efficiently as possible.
    Preview · Article · Nov 2014 · International surgery
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    ABSTRACT: The occurrence of intra-abdominal sterile abscesses due to remnant clips after laparoscopic sigmoidectomy is rare. Here, we report one such case in a 74-year-old woman. Two years after laparoscopic sigmoidectomy, abdominal CT indicated an area of fluid accumulation approximately 5 cm in diameter and located in the middle of the abdominal cavity that contained a cluster of clips. Fine-needle aspiration of the fluid was performed through the wall of the sigmoid colon. The luminal fluid was found not to contain cancer cells on histological examination. After 1 year, abdominal surgery was performed. The abscess was located in the mesorectum at the anastomosis site; it was incised and a significant quantity of ivory-white viscous solution containing a cluster of clips was extracted. This case emphasizes the importance of reducing the number of clips used in laparoscopic surgery.
    No preview · Article · Aug 2014 · Asian Journal of Endoscopic Surgery
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    ABSTRACT: Abstract Preoperative management of advanced rectal cancer often includes chemoradiotherapy, but little is known about the late complications of radiotherapy. However, these are usually serious, making determination of the characteristics of late complications after radiation therapy critical. Accordingly, we investigated the complications occurring after adjuvant pelvic radiation therapy in patients with advanced rectal cancer. We enrolled 34 consecutive patients with TNM stage III rectal cancer who had undergone curative surgery with adjuvant pelvic radiation therapy. Data on the type of complication/organ involved, the number of complications, the phase of onset, and the treatments used were reviewed. Patients who experienced gut complications or edema were less likely to have their complications resolved than those with complications due to infection. Similarly, patients with multiple complications and late-onset complications were also less likely to have their complications resolved than those with single complications and those with early-onset complications, respectively. Adjuvant radiation therapy in patients with resected advanced rectal cancer was associated with various complications, characterized by late onset and impaired resolution. Therefore, patients indicated for radiation therapy should be selected with great caution.
    No preview · Article · Mar 2014 · International surgery
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    ABSTRACT: Abstract : A retrospective study was conducted to decide the indication for pylorus-preserving gastrectomies (PPG). We enrolled consecutive 2173 patients who were treated with distal gastrectomy or total gastrectomy along with lymphadenectomy more than D1 as radical operation for gastric cancer. The incidence of peripyloric lymph node metastasis was evaluated with reference to the depth of invasion, tumor size, and the tumor-pylorus ring distance. The positive rate of lymph node metastasis decreased in proportion to the tumor-pylorus ring distance. On the other hand, the rate increased in proportion to the tumor depth. Among pT1 cases with > 5 cm tumor-pylorus ring distance, peripyloric lymph node metastasis was detected in only 5 cases, which had >= 2 cm tumor size and pSM invasion. Then we set the clinical indication of PPG for cM and cSM (tumor diameter < 2 cm) with > 5 cm pylorus-tumor distance. In a re-evaluation made based on this indication criteria, there was only one (0.2%) case of positive lymph nodes out of 424 PPG indicated cases, however, this was unordinary case with bone metastases 4 years after operation regardless of D2 lymph node dissection. In conclusion, cM or cSM (< 2 cm) gastric cancer situated more than 5 cm distant from the pylorus ring can be a candidate for PPG.
    Preview · Article · Jan 2014 · Nihon Rinsho Geka Gakkai Zasshi (Journal of Japan Surgical Association)
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    ABSTRACT: Novel risk factors for lymph node metastasis (LNM) in T1 colorectal cancer (CRC) have been recently proposed, but most have not been implemented because of the lack of validation. Here we determined the value of poorly differentiated clusters (PDCs) in a multi-institutional cohort of T1 CRC cases. A pathology review involving 30 institutions was conducted for 3556 T1 CRCs. PDC was defined as malignant clusters comprising ≥5 cells and lacking a glandular formation. The ability to identify LNM risk was compared using Akaike's information criterion (AIC). PDC was observed in 1401 tumors (39.4 %), including 94 (17.8 %) with <1000 µm submucosal invasion and 1307 (43.2 %) with ≥1000 µm submucosal invasion (P < 0.0001). The incidence of LNM was higher in PDC-positive tumors (17.4 %) than in PDC-negative tumors (6.9 %; P < 0.0001), and PDCs had an adverse impact on LNM irrespective of the degree of submucosal invasion. Grade 3, vascular invasion, budding, and submucosal invasion depth were also significant factors (all, P < 0.0001). AIC of risk factor to identify LNM risk was most favorable for vascular invasion (2273.4), followed by PDC (2357.4); submucosal invasion depth (2429.1) was the most unfavorable. Interinstitutional judgment disparities were smaller in PDC (kappa, 0.51) than vascular invasion (0.33) or tumor grade (0.48). PDC is a promising new parameter with good ability to identify LNM risk. Use of its appropriate judgment criteria will enable us determine whether an observational policy can be safely applied following local tumor excision in T1 CRC cases.
    No preview · Article · Sep 2013 · Journal of Gastroenterology