CT is unreliable in locoregional staging of early colon cancer: A nationwide registry-based study

BACKGROUND AND OBJECTIVE

The option to treat early colon cancer (CC) with local resection, as well as trials investigating neoadjuvant treatment, has increased the importance of identifying early-stage disease in the workup. Most CC patients are T- and N-staged preoperatively with CT, although its reliability in staging early CC remains elusive. The aim of this study was to investigate CT-staging accuracy in early CC by evaluating pT and pN stages in patients staged as cT1-2, and cT and cN stages in patients with pT1 tumors.

METHODS

Retrospective population-based cohort study on data from the nationwide Swedish colorectal cancer registry on all CC patients staged as cT1-2 and all patients with pT1 undergoing surgical resection 2009-2018. CT-acquired T- and N-stages were compared with final histopathology. Factors potentially influencing accuracy were analyzed with uni- and multivariate logistic regression.

RESULTS

Computed tomography (CT) staged 4849 patients as cT1-2, whereas 2445 (50%) were pT3 and 453 (9%) pT4. Positive predictive value of the cT1-2 stage was 40%. Of 1401 pT1 patients, 624 (45%) were staged as cT1-2, 139 (10%) as cT3, 15 (1%) as cT4 and 623 (44%) as cTx. In all, 1474 (30%) of the cT1-2 patients were pN+, whereas CT staged 1062 (72%) as cN0. A total of 771 patients were staged as cN+, whereas 403 (52%) were pN0. Overall accuracy in determining N+ was 67%, with 26% sensitivity and 88% specificity. Positive and negative predictive values in determining N+ were 48% and 73%, respectively.

CONCLUSIONS

This nationwide population-based study shows that CT-staging carries a substantial risk of understaging locally advanced tumors as cT1-2 and pT1 tumors as cTx, in addition to poor N-staging. Thus, CT obtained T- and N-staging should not be used for deciding treatment strategies in early CC.

Incidence and Outcomes of Early Cancers After Kidney Transplantation

Outcomes of early cancers after kidney transplantation are not well-understood. We included recipients of first live and deceased donor kidney transplants who developed de novo cancers in Australia and New Zealand between 1980–2016. We compared the frequency and stage of specific cancer types that developed early (≤12-months) and late (>12-months) post-transplantation. Risk factors for death were evaluated using multivariable Cox regression analyses. Of 2,759 recipients who developed de novo cancer, followed-up for 40,035 person-years, 243 (8.8%) patients were diagnosed with early cancer. Post-transplant lymphoproliferative disease, urinary cancers and melanoma were the most common cancer types (26%, 18%, and 12%) and the majority were either in-situ or locally invasive lesions (55%, 84%, and 86%). Tumors arising early from the gastrointestinal and respiratory systems were uncommon but aggressive, with 40% presenting with metastatic disease at time of diagnosis. Overall, 32% of patients with early cancers died within a median of 4.7 months (IQR:0.6–16) post-diagnosis and 91% were cancer-related deaths. Older recipient and donor age were associated with an increased risk of all-cause death. Early cancers, though infrequent in kidney transplant recipients, are associated with poor outcomes, as nearly 1 in 3 died from cancer-related death; with majority of deaths occurring within 12-months of cancer diagnosis.

Acute appendicitis after colorectal endoscopic mucosal resection: a case report

Endoscopic mucosal resection (EMR) was originally described in 1973 and is currently a popular practice used in treating polyps, small adenomas, and early cancers. Although the safety of EMR has been proven in numerous studies, complications occur occasionally. We report a case in which the patient complained of severe upper abdominal pain and who was diagnosed with acute appendicitis after colorectal EMR. The patient recovered well after surgery. Cautious observation is necessary when resuming oral intake in patients who undergo colorectal EMR and who complain of postoperative abdominal pain. Observation is especially important for patients with a fecalith that may have originally existed in the appendix or in the colon near the appendix.

Population-level Outcomes of Early Thyroid Cancers: A Need to Revisit Current Practice

BACKGROUND

Early thyroid cancers have excellent long-term outcomes, yet the word "cancer" draws unnecessary apprehension. This study aimed to define when the recommendations for observation and surveillance may be extended to early thyroid cancers at the population level.

METHODS

Non-metastasized thyroid cancers ≤40 mm diameter were identified from the 1975-2016 Surveillance, Epidemiology and End Results (SEER) database. Causes of death were compared across demographic data. Disease-specific outcomes were compared to the age-adjusted healthy United States (US) population. Survival estimates were computed using Kaplan-Meier and compared using the Cox proportional hazard model. Dynamic benchmarks impacting disease-specific overall survival were determined by decision tree modeling and tested by the Cox model.

RESULTS

Of the 28,728 thyroid cancers included in this study, 98.4% underwent some form of thyroid-specific treatment and were followed for a maximum of 10.9 years. This group had a 4.3% mortality rate at the end of follow-up (10.9 years maximum), with 13 times more deaths attributed to competing risks rather than thyroid cancer (stage T1a versus stage T1b, P=1.000; T1 versus T2, P<0.001). Among the untreated T1a or T1b tumors, the risk of disease-specific death was 21 times lower than death due to other causes. There was no significant difference between T1a and T1b tumors nor across sex. The age-adjusted risk of death for the healthy US population was higher than for the population with thyroid cancer. Dynamic categorization demonstrated worsening outcomes up to 73 years, uninfluenced by sex or tumor size. For patients over 73 years of age, only tumors >26 mm impacted outcomes.

CONCLUSION

Based on the current data, T1a and T1b nodules have similar survival outcomes and are not significantly impacted even when left untreated. Multi-institutional prospective studies are needed to confirm these findings so that current observation and surveillance recommendations can be extended to certain T1 thyroid nodules.

Early gastric cancer

Early gastric cancer is defined histopathologically as a tumour with limited local progression to the mucosa and submucosa. The concept of early cancer was developed in the 1960s in Japan and is now widely accepted. The term of early gastric cancer included cases with/without metastatic lymph node involvement. However, a common characteristic is a favourable prognosis of the disease. The task of the endoscopist is primarily to diagnose (identify) the tumour (precancerous lesions) and to verify it by biopsy. Successful identification must be followed by its correct classification, leading to the choice of an adequate approach, which includes surveillance, endoscopic treatment (resection) or surgical treatment (with or without chemotherapy). The method of treatment is determined primarily by the nature or risk of lymph node involvement.

Characterisation of dysplastic liver nodules using low-pass DNA sequencing and detection of chromosome arm-level abnormalities in blood-derived cell-free DNA

High-grade dysplasia carries significant risk of transformation to hepatocellular carcinoma (HCC). Despite this, at the current standard of care, all non-malignant hepatic nodules including high-grade dysplastic nodules are managed similarly. This is partly related to difficulties in distinguishing high-risk pathology in the liver. We aimed to identify chromosome arm-level somatic copy number alterations (SCNAs) that characterise the transition of liver nodules along the cirrhosis-dysplasia-carcinoma axis. We validated our findings on an independent cohort using blood-derived cell-free DNA. A repository of non-cancer DNA sequences obtained from patients with HCC (n = 389) was analysed to generate cut-off thresholds aiming to minimise false-positive SCNAs. Tissue samples representing stages from the multistep process of hepatocarcinogenesis (n = 184) were subjected to low-pass whole genome sequencing. Chromosome arm-level SCNAs were identified in liver cirrhosis, dysplastic nodules, and HCC to assess their discriminative capacity. Samples positive for 1q+ or 8q+ arm-level duplications were likely to be either HCC or high-grade dysplastic nodules as opposed to low-grade dysplastic nodules or cirrhotic tissue with an odds ratio (OR) of 35.5 (95% CI 11.5-110) and 16 (95% CI 6.4-40.2), respectively (p < 0.0001). In an independent cohort of patients recruited from Nottingham, UK, at least two out of four alterations (1q+, 4q-, 8p-, and 8q+) were detectable in blood-derived cell-free DNA of patients with HCC (n = 22) but none of the control patients with liver cirrhosis (n = 9). Arm-level SCNAs on 1q+ or 8q+ are associated with high-risk liver pathology. These can be detected using low-pass sequencing of cell-free DNA isolated from blood, which may be a future early cancer screening tool for patients with liver cirrhosis. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

Predictive Value of Carcinoembryonic Antigen in Symptomatic Patients without Colorectal Cancer: A Post-Hoc Analysis within the COLONPREDICT Cohort

We aimed to assess the risk of cancer in patients with abdominal symptoms after a complete colonoscopy without colorectal cancer (CRC), according to the carcinoembryonic antigen (CEA) concentration, as well as its diagnostic accuracy. For this purpose, we performed a post-hoc analysis within a cohort of 1431 patients from the COLONPREDICT study, prospectively designed to assess the fecal immunochemical test accuracy in detecting CRC. Over 36.5 ± 8.4 months, cancer was detected in 115 (8%) patients. Patients with CEA values higher than 3 ng/mL revealed an increased risk of cancer (HR 2.0, 95% CI 1.3-3.1), CRC (HR 4.4, 95% CI 1.1-17.7) and non-gastrointestinal cancer (HR 1.7, 95% CI 1.0-2.8). A new malignancy was detected in 51 (3.6%) patients during the first year and three variables were independently associated: anemia (OR 2.8, 95% CI 1.3-5.8), rectal bleeding (OR 0.3, 95% CI 0.1-0.7) and CEA level >3 ng/mL (OR 3.4, 95% CI 1.7-7.1). However, CEA was increased only in 31.8% (95% CI, 16.4-52.7%) and 50% (95% CI, 25.4-74.6%) of patients with and without anemia, respectively, who would be diagnosed with cancer during the first year of follow-up. On the basis of this information, CEA should not be used to assist in the triage of patients presenting with lower bowel symptoms who have recently been ruled out a CRC.

Safety and efficacy of endoscopic submucosal dissection for metachronous early cancer or precancerous lesions emerging at the anastomotic site after curative surgical resection of colorectal cancer

Background

The incidence of metachronous early cancer or precancerous lesions (MECPL) emerging at the anastomotic site (AS) after curative surgical resection of colorectal cancer (CRC) is so low that few study have been conducted to explore the clinical characteristics, diagnosis and treatment of these lesions. Endoscopic submucosal dissection (ESD) is technically difficult for these lesions because of the presence of severe fibrosis and AS. The aim of this study was to explore the safety and efficacy of ESD for MECPL emerging at the AS after curative surgical resection of CRC.

Methods

The data used in the analysis were retrospectively collected from CICAMS in Beijing China between January 2013 and May 2019 and from all the patients who underwent ESD for MECPL emerging at the AS after curative surgical resection of CRC. The rates of en bloc resection (ER), complete resection (CR), curative resection (CuR) and incidence of complications were analyzed by SPSS software.

Results

A total of 11 patients were included. The rates of ER, CR and CuR were 63.6%, 54.5% and 54.5%, respectively. No additional surgery was performed, and no recurrences were found. Bleeding occurred in only one case and there was no perforation after the operation.

Conclusions

Overall, ESD is safe and effective in the treatment of MECPL emerging at the AS after curative surgical resection of CRC. Especially for patients with anastomotic recurrence close to anal margin, this method can avoid the risks of reoperation and improve the rate of anal preservation.

Treatment and relapse in breast cancer show significant correlations to noninvasive testing using urinary and plasma DNA

Aim: Circulating tumor DNA is promising for routine monitoring of breast cancer. Noninvasive testing allows regular probing using plasma and urine samples. Methods: Peripheral blood and simultaneous urine collection from patients were quantified. Concordance between methods were made. Serial time-point measurements were correlated to disease outcome. Results: Index measurements demonstrate over 90% concordance with biopsy. Receiver operating characteristics curves showed over 0.95 for both plasma and urine results comparing with controls. Patients with lower risk of relapse experienced greater declines in detected DNA levels. Maximal declines were registered at 4.0- and 6.8-fold for plasma and urine results, respectively. Conclusion: Measuring and monitoring DNA levels complement existing testing regimes and provides better risk profiling of patients for possible relapse.

Predicting lymph node metastases with endoscopic resection in cT2N0M0 oesophageal cancer: A systematic review and meta-analysis

Background

Despite modern imaging modalities, staging of clinically staged T2N0M0 (cT2N0M0) oesophageal cancer is suboptimal, often leading to overtreatment. Endoscopic resection – the first-line therapy for early localised tumours – could be used to improve staging and to attain predictors of nodal upstaging enabling more stage-guided treatment decisions.

Objective

A systematic literature review and a meta-analysis were conducted to assess the prevalence and the pathological risk factors of lymph node metastases in cT2N0M0 oesophageal cancer.

Methods

Databases of PUBMED, EMBASE and Cochrane were searched for literature. The primary outcome was lymph node metastases determined after primary surgical resection.

Results

Nine studies with a total of 1650 cT2N0M0 patients were included. The prevalence of lymph node metastases was 43% (95% confidence interval: 35–50%) with heterogeneity being high across studies (I² = 0.86, p < 0.001). Factors potentially attainable by endoscopic resection and having a significant association with lymph node metastases were invasion depth, differentiation grade, tumour size, depth of invasion in the muscularis propria and lymphovascular invasion.

Conclusions

Clinical lymph node staging is inaccurate in almost half of cT2N0M0 oesophageal cancer. Endoscopic resection is a promising diagnostic modality that might even be a valid alternative to surgery in selected patients without high-risk features, but further evidence is warranted.

The Role of Transabdominal Ultrasound in the Diagnosis of Early Stage Pancreatic Cancer: Review and Single-Center Experience

Pancreatic cancer (PC) is the fourth leading cause of cancer-related death with a 5-year survival rate less than 10%. In the absence of effective screening methods, such as blood markers, most clinical diagnoses of PC are made at an advanced stage. However, early stage PC is associated with a more favorable five-year survival rate of 85.8% for stage 0, and 68.7% for stage IA. Transabdominal ultrasound (US) is frequently used as a first-line diagnostic tool in the clinical setting and a preferred modality for routine medical evaluations for asymptomatic individuals. Recently published Japanese data show that most PCs diagnosed in early stage had US findings, such as dilated main pancreatic ducts or pancreas cysts. For surveillance of high-risk individuals, such as those with an intraductal papillary mucinous neoplasm (IPMN), US is an ideal modality in terms of its non-invasive and cost-effective nature. However, the diagnostic performance of ultrasound varies greatly by the operator’s experience and the patient’s condition. This article reviews the present situation of early diagnosis of pancreatic cancer by US, along with tips for improving visualization of the pancreas.

Signature Gene Identification of Cancer Occurrence and Pattern Recognition

To identify signature genes for the pathogenesis of cancer, which provides a theoretical support for prevention and early diagnosis of cancer. The pattern recognition method was used to analyze the genome-wide gene expression data, which was collected from the The Cancer Genome Atlas (TCGA) database. For the transcription of invasive breast carcinoma, lung adenocarcinoma, lung squamous cell carcinoma, colon adenocarcinoma, renal clear-cell carcinoma, thyroid carcinoma, and hepatocellular carcinoma of the seven cancers, the signature genes were selected by means of a combination of statistical methods, such as correlation, t-test, confidence interval, etc. Modeling by artificial neural network model, the accuracy can be as high as 98% for the TCGA data and as high as 92% for the Gene Expression Omnibus (GEO) independent data, the recognition accuracy of stage I is more than 95%, which is higher compared with the previous study. The common genes emerging in five cancers were obtained from the signature genes of seven cancers, PID1, and SPTBN2. At the same time, we obtain three common pathways of cancer by using Kyoto Encyclopedia of Genes and Genomes' pathway analysis. A functional analysis of the pathways shows their close relationship at the level of gene regulation, which indicted that the identified signature genes play an important role in the pathogenesis of cancer and is very important for understanding the pathogenesis of cancer and the early diagnosis.

A single-step sizing and radiofrequency ablation catheter for circumferential ablation of Barrett's esophagus: Results of a pilot study

Background

The 360 Express balloon catheter (360 Express) has the ability to self-adjust to the esophageal lumen, ensuring optimal tissue contact.

Objective

The objective of this article is to evaluate the efficacy and safety of the 360 Express for radiofrequency ablation (RFA) treatment of Barrett's esophagus (BE).

Methods

BE patients with low-grade dysplasia (LGD), high-grade dysplasia (HGD) or early cancer (EC) were included. Visible lesions were removed by endoscopic resection (ER) prior to RFA. RFA was performed with the 360 Express using the standard ablation regimen (12J/cm²–clean–12J/cm²). Primary outcome: BE regression percentage at three months. Secondary outcomes: procedure time, adverse events, complete eradication of dysplasia (CE-D) and intestinal metaplasia (CE-IM).

Results

Thirty patients (median BE C4M6) were included. Eight patients underwent ER prior to RFA. Median BE regression: 90%. Median procedure time: 31 minutes. Adverse events (13%): laceration (n = 1); atrial fibrillation (n = 1); vomiting and dysphagia (n = 1); dysregulated diabetes (n = 1). After subsequent treatment CE-D and CE-IM was achieved in 97% and 87%, respectively. In 10% a stenosis developed during additional treatment requiring a median of one dilation.

Conclusion

This study shows that circumferential RFA using the 360 Express may shorten procedure time, while maintaining efficacy compared to standard circumferential RFA.

Efficacy of docetaxel, cisplatin, and 5-fluorouracil chemotherapy for superficial esophageal squamous cell carcinoma

The anticancer efficacy of docetaxel, cisplatin, and 5-fluorouracil (DCF) chemotherapy has been reported to be better than that of conventional regimens for advanced or relapsed esophageal squamous cell carcinoma (ESCC), and may become a standard therapy for this disease. Because it is extremely rare for chemotherapy to be administered as treatment for early cancer alone, the efficacy of DCF for superficial ESCC remains unknown. However, from a clinical oncological standpoint, it is important to investigate the anticancer efficacy of chemotherapy for early cancer, which may be useful for understanding the development of treatment resistance against chemotherapy in cancer. This retrospective, single-center analysis included 28 patients with superficial ESCC who received DCF for synchronous head and neck squamous cell carcinoma between June 2007 and July 2013. The response rate to DCF was 60.7%. In 14 of 17 patients who had been judged to have a complete response, local recurrence was eventually confirmed by follow-up esophagogastroduodenoscopy. The median progression-free survival for all 28 patients was 6.0 months. The anticancer efficacy of DCF was not found to be dependent on tumor progression stage or on the volume of local and metastatic tumors but on the drug sensitivity of the individual. Our results suggest that the efficacy of DCF against superficial esophageal squamous cell carcinoma appears to be limited to local lesions and metastases of regional lymph nodes, and the expected effect of DCF for early ESCC is similar to that for advanced, metastatic, or recurrent esophageal cancer.

Early hepatocellular carcinoma as a signaling lesion for subsequent malignancy

OBJECTIVE

Early diagnosis and treatment of cancer may contribute substantially to complete cure, but it remains unknown whether treatment of early hepatocellular carcinoma can actually result in cure. This study was performed to clarify the cancer risk of the background liver after treating early hepatocellular carcinoma.

METHODS

Early hepatocellular carcinoma is defined as very well-differentiated cancer containing Glisson's triad. The cumulative incidence of classical hepatocellular carcinoma, hypervascular liver cancer detected on imaging studies, after resection of early hepatocellular carcinoma positive for anti-hepatitis C antibody (early hepatocellular carcinoma group, n = 105) was compared with that in patients with chronic liver disease positive for anti-hepatitis C antibody (control group, n = 751) and propensity score-matched patients after resection of classical hepatocellular carcinoma (classical hepatocellular carcinoma group, n = 105).

RESULTS

After a median follow-up of 4.8 years (range, 0.3-15.0), the cumulative incidence of classical hepatocellular carcinoma at 5 years was 56.9% (95% confidence interval, 44.2-67.7%) in the early hepatocellular carcinoma group and 70.6% (52.5-81.8%) in the classical hepatocellular carcinoma group as compared with 4.6% (2.8-6.4%) in the control group. The risk of the development of classical hepatocellular carcinoma in the early hepatocellular carcinoma group was significantly higher than that in the control group (hazard ratio, 17.5; 95% confidence interval, 12.1-25.3; P < 0.001) and significantly lower than that in the classical hepatocellular carcinoma group (hazard ratio, 0.60; 0.41-0.89; P = 0.010). However, the cumulative incidence of second primary hepatocellular carcinoma in patients with one early hepatocellular carcinoma did not differ significantly from that in patients with two or more early hepatocellular carcinoma lesions (hazard ratio, 1.50; 0.85-2.65; P = 0.157).

CONCLUSIONS

Treatment of early hepatocellular carcinoma cannot provide complete cure due to the substantial risk of developing classical hepatocellular carcinoma.

Endoscopic Resection and Radiofrequency Ablation for Early Esophageal Neoplasia

In the last few decades, endoscopic treatment of early neoplastic lesions in the esophagus has established itself as a valid and less invasive alternative to surgical resection. Endoscopic resection (ER) is the cornerstone of endoscopic therapy. Next to the curative potential of ER, by removing neoplastic lesions, ER may also serve as a diagnostic tool. The relatively large tissue specimens obtained with ER enable accurate histological staging of a lesion, allowing for optimal decision-making for further patient management. ER was pioneered in Japan, mainly for the resection of gastric lesions and squamous esophageal neoplasia, and also Western countries have been increasingly implementing ER in the treatment of early gastroesophageal neoplasia, mostly associated with Barrett's esophagus (BE). In BE, however, there is still a risk of metachronous lesions in the remainder of the Barrett's after focal ER. Additional treatment of all Barrett's mucosa is therefore advised. Currently, the most effective method for this is by using radiofrequency ablation (RFA). This review will provide an overview of indications for ER and RFA. Key Messages and Conclusions: Endoscopic management of early esophageal neoplasia is a safe and valid alternative to surgery and is nowadays the treatment of choice. ER is the mainstay of endoscopic management of early esophageal neoplasia since it allows for removal of neoplastic lesions and provides a large tissue specimen for histological evaluation. In case of early neoplasia in BE, focal ER should be complemented by eradication of the remaining Barrett's mucosa. RFA has proven to be a safe and effective modality to achieve complete eradication of Barrett's mucosa.

Magnifying endoscopy simple diagnostic algorithm for early gastric cancer (MESDA-G)

Gastric cancer is the third leading cause of cancer death worldwide. Early detection and accurate diagnosis of mucosal cancer is desirable in order to achieve decreased mortality; cause-specific survival of patients with early gastric cancer is reported to exceed 95%. Endoscopy is the functional modality to detect early cancer; however, the procedure is not definitive when using conventional white-light imaging. In contrast, magnifying narrow-band imaging (M-NBI), a novel endoscopic technology, is a powerful tool for characterizing gastric mucosal lesions because it can visualize the microvascular architecture and microsurface structure. To date, many reports on the diagnosis of early gastric cancer by M-NBI, including multicenter prospective randomized studies conducted in Japan, have been published in peer-reviewed international journals. Based on these published data, we devised a proposal for a diagnostic strategy for gastric mucosal cancer using M-NBI to simplify the process of diagnosis and improve accuracy. Herein, we recommend a diagnostic algorithm for early gastric cancer using magnifying endoscopy.

Endoscopic diagnosis of early Barrett's neoplasia: perspectives for advanced endoscopic technology

Barrett's esophagus (BE) is a metaplastic condition that occurs secondary to gastroesophageal reflux disease. BE is also a precursor to esophageal adenocarcinoma, which, although still rare in Japan, is one of the most rapidly increasing cancers in Western countries. However, the prevalence of gastroesophageal reflux disease has increased significantly over the past few decades in Japan, possibly leading to an incremental rise in BE and the associated inherent risk of adenocarcinoma. Given the poor prognosis of advanced-stage Barrett's adenocarcinoma, endoscopic surveillance is recommended for subjects with BE to detect early neoplasias including dysplasia. However, endoscopic identification of dysplastic lesions is still not sufficiently reliable or subjective, making targeted therapy extremely difficult. Over the past few years, improvements in image resolution, image processing software, and optical filter technology have enabled identification of dysplasia and early cancer in BE patients. We retrieved as many studies on advanced endoscopic technologies in BE as possible from MEDLINE and PubMed. The present review focuses on the emergent clinically available technologies to provide an overview of the technologies, their practical applicability, current status, and future challenges.

Endoscopic methods in the treatment of early-stage esophageal cancer

Most patients with early esophageal cancer restricted to the mucosa may be offered endoscopic therapy, which is similarly effective, less invasive and less expensive than esophagectomy. Selection of appropriate relevant treatment and therapy methods should be performed at a specialized center with adequate facilities. The selection of an endoscopic treatment method for high-grade dysplasia and early-stage esophageal adenocarcinoma requires that tumor infiltration is restricted to the mucosa and that there is no neighboring lymph node metastasis. In squamous cell carcinoma, this treatment method is accepted in cases of tumors invading only up to the lamina propria of mucosa (m2). Tumors treated with the endoscopic method should be well or moderately differentiated and should not invade lymphatic or blood vessels. When selecting endoscopic treatments for these lesions, a combination of endoscopic resection and endoscopic ablation methods should be considered.

The Natural History of pT1 Colorectal Cancer

Colorectal carcinoma invading the submucosa but not the muscular layer (pT1, early invasive cancer) represents the earliest form of clinically relevant colorectal cancer in most patients. Neoplastic invasion of the submucosa, in fact, opens the way to metastasis via the lymphatic and blood vessels, and the choice between surveillance and major surgery will turn on its metastatic potential. The following histological features predict the risk of metastasis and the different clinical outcomes: grade of differentiation of carcinoma, lymphovascular invasion, state of the resection margin. Microstaging of invasive cancer, namely the width and the depth of submucosal invasion, together with tumor budding at the advancing edge allow the metastatic risk to be further stratified in minimal, low, and high. Different, although morphologically undistinguishable, tumorigenic pathways are supposed to lead to the malignant transformation of colonic mucosa and subsequently to drive the progression from early to advanced cancer: new biomarkers are needed to identify progressive and non-progressive pT1 neoplasia.

CA19-9-producing early gastric adenocarcinoma arising in hyperplastic foveolar polyp: a very unique resection case

Here we report the first case of carbohydrate antigen (CA) 19-9-producing early gastric adenocarcinoma arising in polyp. A solitary pedunculated polyp lesion of the stomach, measuring 26 × 20 × 20 mm, was noticed in a 76-year-old Japanese woman due to an abdominal disorder, associated with a markedly high serum CA19-9 level (2,172.6 U/ml). After endoscopic mucosal resection was performed, the CA19-9 level was drastically decreased and normalized. The scanning view of immunohistochemical staining of CA19-9 exhibited a focal, not diffuse, positive-expression in the hyperplastic epithelium and, especially, in the irregular and fused tubular glands and the mucinous material secreted into the dilated glands. In particular, microscopic examination of the strongly CA19-9-positive areas showed structurally atypical epithelium containing mildly to focal moderately enlarged nuclei and prominent nucleoli with loss of cellular polarity, estimated as adenocarcinoma. No stromal invasion was evident. Immunohistochemically, distinct nuclear stainings for p53 and Ki-67 were seen, occasionally conforming to the CA19-9-positive atypical cells, respectively, confirmed by double immunostaining. These hyperplastic and atypical cells were classified into the pure gastric phenotype by mucin histochemical methods. Based on these features, we finally made a conclusive diagnosis of CA19-9-producing in situ well differentiated adenocarcinoma of gastric type arising in hyperplastic foveolar polyp. We suggest that the markedly high serum CA 19-9 level could be indicative of carcinoma in polyp at the very least.

Prevention of gastrointestinal cancer by surveillance endoscopy

The classification of the endoscopic appearance of superficial neoplastic lesions of the digestive mucosa aims to evaluate the risk of progression to advanced neoplasia in 3° (low, intermediate, high) and to predict appropriate treatment and corresponding surveillance. The privileged position of endoscopy results from its double impact on prevention of digestive cancer through reduction in incidence after early detection and eradication of precursors; and through reduction of mortality after detection and treatment of cancer at an early and curable stage. However the efficacy of diagnostic endoscopy still requires improvement and quality control on the following points: (1) technology, with a generalized use of the recently introduced high-resolution endoscopes. (2) diagnosis of poorly visible nonpolypoid precursors: this applies to small depressed lesions and large slightly elevated or sessile serrated and non-serrated precursors, particularly in the proximal colon. (3) treatment and training in therapeutic endoscopy, including the most recent techniques of mucosal resection of nonpolypoid lesions.

Increased plasma levels of 8-hydroxydeoxyguanosine are associated with development of colorectal tumors

Increased oxidative stress is generally thought to be associated with tumorigenesis. In this cross-sectional study, we evaluated plasma 8-hydroxydeoxyguanosine (8-OHdG) levels in patients with colorectal adenoma and cancer, as a surrogate marker of oxidative damage to deoxyribonucleic acid (DNA). We collected blood samples from 58 patients with adenoma, 32 with early cancer, 25 with advanced cancer, and 36 without polyps or cancer (as controls), and measured plasma levels of 8-OHdG by enzyme-linked immunosorbent assay. Univariate analysis by logistic regression showed that an increased level of 8-OHdG was a significant risk for adenoma [odds ratio (OR) 1.393, 95% confidence interval (CI) 1.008-1.926, p = 0.045]. In patients with early cancer, univariate analysis revealed significant differences for age, body mass index (BMI), systolic blood pressure, and 8-OHdG level. Subsequent multivariate analysis revealed that 8-OHdG [OR 1.627, 95% CI 1.079-2.453, p = 0.020] and BMI [OR 1.283, 95% CI 1.038-1.585, p = 0.021] were significant risk factors for early cancer. However, 8-OHdG was not a significant risk factor for advanced cancer. Our results suggest that an increased plasma level of 8-OHdG is associated with development of colorectal adenoma and cancer.

A novel treatment for early gastrointestinal carcinoma by ultrasonic endoscopic mucosal stripping

PURPOSE

The aim of this study was to clarify the indications for a new endoscopic mucosal resection (EMR) technique that employs a cavitational ultrasonic surgical aspirator (CUSA). Endoscopic mucosal resection has proved an effective technique for treating early mucosal gastrointestinal cancer. However, resecting a lesion larger than 2 cm en bloc requires special devices and a long processing time; and it engenders the risk of bleeding, perforation, and other complications.

METHODS

We investigated application of the CUSA for detaching the mucosa from the muscularis propria of extracted porcine stomachs and then clarified the specification of an endoscopic ultrasonic scalpel for endoscopic mucosal resection by investigating characteristics of two original, handmade prototype cavitational ultrasonic surgical aspirators.

RESULTS

Use of a cavitational ultrasonic surgical aspirator should improve the ease and safety of detaching the mucosa. A small, high-power ultrasonic cylindrical vibrator should be developed to make possible a probe-type scalpel with a piezoelectric vibrator mounted in the tip of a catheter. An ultrasonic transmission-type scalpel could lead to the development of a new endoscopic mucosal resection device for clinical use.

CONCLUSIONS

The CUSA should enable us to develop a safer, simpler, time-saving scalpel for endoscopic mucosal resection, although some resolvable technical problems remain. The CUSA might enable us to diagnose carcinoma invasion into the submucosa in aspirated specimens and then aspirate out the entire invading submucosal carcinoma.