Cost-utility of real-time continuous glucose monitoring versus self-monitoring of blood glucose in people with insulin-treated Type II diabetes in France

Aim: Clinical trials and real-world data for Type II diabetes both show that glycated hemoglobin (HbA1c) levels and hypoglycemia occurrence can be reduced by real-time continuous glucose monitoring (rt-CGM) versus self-monitoring of blood glucose (SMBG). The present cost-utility study investigated the long-term health economic outcomes associated with using rt-CGM versus SMBG in people with insulin-treated Type II diabetes in France. Materials & methods: Effectiveness data were obtained from a real-world study, which showed rt-CGM reduced HbA1c by 0.56% (6.1 mmol/mol) versus sustained SMBG. Analyses were conducted using the IQVIA Core Diabetes Model. A French payer perspective was adopted over a lifetime horizon for a cohort aged 64.5 years with baseline HbA1c of 8.3% (67 mmol/mol). A willingness-to-pay threshold of €147,093 was used, and future costs and outcomes were discounted at 4% annually. Results: The analysis projected quality-adjusted life expectancy was 8.50 quality-adjusted life years (QALYs) for rt-CGM versus 8.03 QALYs for SMBG (difference: 0.47 QALYs), while total mean lifetime costs were €93,978 for rt-CGM versus €82,834 for SMBG (difference: €11,144). This yielded an incremental cost-utility ratio (ICUR) of €23,772 per QALY gained for rt-CGM versus SMBG. Results were particularly sensitive to changes in the treatment effect (i.e., change in HbA1c), annual price and quality of life benefit associated with rt-CGM, SMBG frequency, baseline patient age and complication costs. Conclusion: The use of rt-CGM is likely to be cost-effective versus SMBG for people with insulin-treated Type II diabetes in France.

Cost-utility of real-time continuous glucose monitoring versus self-monitoring of blood glucose in people with insulin-treated Type 2 diabetes in Canada

Aim: Clinical trials and real-world data for Type 2 diabetes have shown that real-time continuous glucose monitoring (rt-CGM) lowers glycated hemoglobin (A1c) and reduces hypoglycemia relative to self-monitoring of blood glucose (SMBG). This analysis examined the long-term health and economic outcomes associated with using rt-CGM versus SMBG in people with insulin-treated Type 2 diabetes in Canada. Materials & methods: Clinical data were sourced from a real-world study, in which rt-CGM reduced A1C by 0.56% versus continued SMBG. The analysis was performed using the IQVIA Core Diabetes Model, from a Canadian payer perspective over a lifetime horizon for a cohort aged 65 years with an A1C of 8.3% at baseline. Future costs and clinical outcomes were discounted at 1.5% annually. Results: Projected total mean lifetime costs were CAD 207,466 for rt-CGM versus CAD 189,863 for SMBG (difference: CAD 17,602) and projected mean quality-adjusted life expectancy was 9.97 quality-adjusted life years (QALYs) for rt-CGM versus 9.02 QALYs for SMBG (difference: 0.95 QALYs), resulting in an incremental cost-utility ratio (ICUR) of CAD 18,523 per QALY gained for rt-CGM versus SMBG. Findings were sensitive to changes in the A1C treatment effect, annual cost and quality of life benefit associated with using rt-CGM, SMBG frequency, and baseline age, but ICURs remained below CAD 50,000 per QALY in all analyses. Conclusion: For people in Canada with insulin-treated Type 2 diabetes and poor glycemic control, use of rt-CGM is likely to be cost-effective relative to SMBG.

Cost-utility of real-time continuous glucose monitoring versus self-monitoring of blood glucose and intermittently scanned continuous glucose monitoring in people with type 1 diabetes receiving multiple daily insulin injections in Denmark

AIMS

To determine the cost-effectiveness of the Dexcom G6 real-time continuous glucose monitoring (rt-CGM) system compared with both the self-monitoring of blood glucose (SMBG) and the Abbott FreeStyle Libre 1 and 2 intermittently scanned CGM (is-CGM) devices in people with type 1 diabetes receiving multiple daily insulin injections in Denmark.

MATERIALS AND METHODS

The analysis was performed using the IQVIA Core Diabetes Model, which associates rt-CGM use with glycated haemoglobin reductions of 0.6% and 0.36% based on data from the DIAMOND and ALERTT1 trials, respectively, compared with SMBG and is-CGM use. The analysis was performed from the payer perspective over a 50-year time horizon; future costs and clinical outcomes were discounted at 4% per annum.

RESULTS

The use of rt-CGM was associated with an incremental gain of 1.37 quality-adjusted life years (QALYs) versus SMBG. Total mean lifetime costs were Danish Krone (DKK) 894 535 for rt-CGM and DKK 823 474 for SMBG, resulting in an incremental cost-utility ratio of DKK 51 918 per QALY gained versus SMBG. Compared with is-CGM, the use of rt-CGM led to a gain of 0.87 QALYs and higher mean lifetime costs resulting in an incremental cost-utility ratio of DKK 40 879 to DKK 34 367 per QALY gained.

CONCLUSIONS

In Denmark, the rt-CGM was projected to be highly cost-effective versus both SMBG and is-CGM, based on a willingness-to-pay threshold of 1× per capita gross domestic product per QALY gained. These findings may help inform future policies to address regional disparities in access to rt-CGM.

Cost-Effectiveness of a Real-Time Continuous Glucose Monitoring System Versus Self-Monitoring of Blood Glucose in People with Type 2 Diabetes on Insulin Therapy in the UK

INTRODUCTION

Real-time continuous glucose monitoring (rt-CGM) involves the measurement and display of glucose concentrations, potentially improving glucose control among insulin-treated patients with type 2 diabetes (T2D). The present analysis aimed to conduct a cost-effectiveness analysis of rt-CGM versus self-monitoring of blood glucose (SMBG) based on a USA retrospective cohort study in insulin-treated people with T2D adapted to the UK.

METHODS

Long-term costs and clinical outcomes were estimated using the CORE Diabetes Model, with clinical input data sourced from a retrospective cohort study. Patients were assumed to have a baseline glycated hemoglobin (HbA1c) of 8.3%. Patients using rt-CGM were assumed to have a 0.56% reduction in HbA1c based on the mean difference between groups after 12 months of follow-up. Reduced fingerstick testing when using rt-CGM was associated with a quality of life (QoL) benefit. The analysis was performed over a lifetime time horizon from a National Health Service (NHS) perspective, including only direct costs from published data. Future costs and clinical outcomes were discounted at 3.5% per annum. Extensive sensitivity analyses were performed.

RESULTS

Projections showed that rt-CGM was associated with increased quality-adjusted life expectancy of 0.731 quality-adjusted life years (QALYs) and increased mean total lifetime costs of Great British pounds (GBP) 2694, and an incremental cost-effectiveness ratio of GBP 3684 per QALY compared with SMBG. Key drivers of outcomes included HbA1c reduction and reduced fingerstick testing QoL benefit.

CONCLUSIONS

Over patient lifetimes, rt-CGM was associated with improved clinical outcomes and is highly likely to be cost effective versus SMBG in people with T2D on insulin therapy in the UK.

Association Between Real-Time Continuous Glucose Monitor Use and Diabetes-Related Medical Costs for Patients with Type 2 Diabetes

Little is known about the impact of real-time continuous glucose monitoring (rtCGM) on diabetes-related medical costs within the type 2 diabetes (T2D) population. A retrospective analysis of administrative claims data from the Optum Research Database was conducted. Changes in diabetes-related health care resource utilization costs were expressed as per-patient-per-month (PPPM) costs. A total of 571 T2D patients (90% insulin treated) met study inclusion criteria. Average PPPM for diabetes-related medical costs decreased by -$424 (95% confidence interval [CI] -$816 to -$31, P = 0.035) after initiating rtCGM. These reductions were driven, in part, by reductions in diabetes-related inpatient medical costs: -$358 (95% CI -$706 to -$10, P = 0.044). Inpatient hospital admissions were reduced on average -0.006 PPPM (P = 0.057) and total hospital days were reduced an average of -0.042 PPPM (P = 0.139). These findings provide real-world evidence that rtCGM use was associated with diabetes-related health care resource utilization cost reductions in patients with T2D.

Colorectal premalignancy is associated with consensus molecular subtypes 1 and 2

Background

Gene expression-based profiling of colorectal cancer (CRC) can be used to identify four molecularly homogeneous consensus molecular subtype (CMS) groups with unique biologic features. However, its applicability to colorectal premalignant lesions remains unknown.

Patients and methods

We assembled the largest transcriptomic premalignancy dataset by integrating different public and proprietary cohorts of adenomatous and serrated polyps from sporadic (N = 311) and hereditary (N = 78) patient populations and carried out a comprehensive analysis of carcinogenesis pathways using the CMS random forest (RF) classifier.

Results

Overall, transcriptomic subtyping of sporadic and hereditary polyps revealed CMS2 and CMS1 subgroups as the predominant molecular subtypes in premalignancy. Pathway enrichment analysis showed that adenomatous polyps from sporadic or hereditary cases (including Lynch syndrome) displayed a CMS2-like phenotype with WNT and MYC activation, whereas hyperplastic and serrated polyps with CMS1-like phenotype harbored prominent immune activation. Rare adenomas with CMS4-like phenotype showed significant enrichment for stromal signatures along with transforming growth factor-β activation. There was a strong association of CMS1-like polyps with serrated pathology, right-sided anatomic location and BRAF mutations.

Conclusions

Based on our observations made in premalignancy, we propose a model of pathway activation associated with CMS classification in colorectal carcinogenesis. Specifically, while adenomatous polyps are largely CMS2, most hyperplastic and serrated polyps are CMS1 and may transition into other CMS groups during evolution into carcinomas. Our findings shed light on the transcriptional landscape of premalignant colonic polyps and may help guide the development of future biomarkers or preventive treatments for CRC.

Screening adherence and cancer risk perceptions in colorectal cancer survivors with Lynch-like syndrome

Cancer screening recommendations for patients with Lynch-like syndrome (LLS) are not well defined. We evaluated adherence to Lynch syndrome (LS) screening recommendations, cancer risk perceptions, and communication within the families among colorectal cancer (CRC) survivors with LLS. Thirty-four participants with LLS completed a questionnaire about risk perception, adherence to LS screening recommendations, and communication with relatives. Clinical data were obtained from medical records. Most participants (76%) believed they should undergo colonoscopy every 1-2 years. Only 41% correctly interpreted their genetic tests as uninformative negative or as variant of unknown significance for LS. Less than half had had an upper gastrointestinal endoscopy for screening purpose. Among female participants, 86% had been screened for endometrial cancer (EC) and 71% for ovarian cancer. Most participants had informed relatives about the CRC diagnosis and advised them to undergo CRC screening, but only 50% advised female relatives to be screened for EC and only one-third advised relatives to have genetic counseling. Most CRC survivors with LLS follow the same cancer screening recommended for LS patients but do not understand the meaning of LLS. Greater care must be devoted to communicating the implications of nondiagnostic germline mutation testing among patients with LLS.

Communication and technology in genetic counseling for familial cancer

When a cancer predisposing germline mutation is detected in an index case, the presence of the underlying syndrome is confirmed and the potential for predictive testing of at-risk relatives is established. However, the reporting of a positive family history does not routinely lead to communication of information about risk to close, much less distant relatives. This review summarizes information technology utilized to address penetration or 'reach' of knowledge of risk within extended families, including the use of telephone and video counseling to reach distant patients, and anticipate novel internet-based processes for communication between investigators and relatives.

Gynecologic cancer screening and communication with health care providers in women with Lynch syndrome

We evaluated knowledge of gynecologic cancer screening recommendations, screening behaviors, and communication with providers among women with Lynch syndrome (LS). Women aged ≥25 years who were at risk for LS-associated cancers completed a semi-structured interview and a questionnaire. Of 74 participants (mean age 40 years), 61% knew the appropriate age to begin screening, 75-80% correctly identified the recommended screening frequency, and 84% reported no previous screening endometrial biopsy. Women initiated discussions with their providers about their LS cancer risks, but many used nonspecific terms or relied on family history. Most were not offered high-risk screening options. While many women were aware of risk-appropriate LS screening guidelines, adherence was suboptimal. Improving communication between women and their providers regarding LS-related gynecologic cancer risk and screening options may help improve adherence.

Changes in screening behaviors and attitudes toward screening from pre-test genetic counseling to post-disclosure in Lynch syndrome families

The purpose of this study was to examine colonoscopy adherence and attitudes toward colorectal cancer (CRC) screening in individuals who underwent Lynch syndrome genetic counseling and testing. We evaluated changes in colonoscopy adherence and CRC screening attitudes in 78 cancer-unaffected relatives of Lynch syndrome mutation carriers before pre-test genetic counseling (baseline) and at 6 and 12 months post-disclosure of test results (52 mutation negative and 26 mutation positive). While both groups were similar at baseline, at 12 months post-disclosure, a greater number of mutation-positive individuals had had a colonoscopy compared with mutation-negative individuals. From baseline to 12 months post-disclosure, the mutation-positive group demonstrated an increase in mean scores on measures of colonoscopy commitment, self-efficacy, and perceived benefits of CRC screening, and a decrease in mean scores for perceived barriers to CRC screening. Mean scores on colonoscopy commitment decreased from baseline to 6 months in the mutation-negative group. To conclude, adherence to risk-appropriate guidelines for CRC surveillance improved after genetic counseling and testing for Lynch syndrome. Mutation-positive individuals reported increasingly positive attitudes toward CRC screening after receiving genetic test results, potentially reinforcing longer term colonoscopy adherence.

Resource utilization with insulin pump therapy for type 2 diabetes mellitus

OBJECTIVES

To evaluate the effects of switching from multiple daily injection (MDI) therapy to insulin pump therapy, also called continuous subcutaneous insulin infusion (CSII), on antidiabetic drug and healthcare resource utilization.

STUDY DESIGN

This study was a retrospective analysis of administrative claims data from a large geographically diverse health plan in the United States from January 1, 2005, through April 30, 2008.

METHODS

Changes in antidiabetic drug use, antidiabetic drug switching and augmentation, and healthcare utilization during the baseline period and after CSII initiation were assessed using paired t test.

RESULTS

There were 3649 possible subjects, of whom 943 met the criteria for analysis. The mean number of antidiabetic drugs used decreased by 46% after CSII initiation, and the mean reduction in antidiabetic drug utilization was 0.67; both were statistically significant. More than one-third of subjects who were taking antidiabetic drugs before CSII initiation discontinued oral therapy after CSII initiation. The number of subjects using multiple antidiabetic drugs significantly decreased after CSII initiation by 58%, and rates of switching or augmenting significantly decreased from 42% at baseline to 25% after CSII initiation.The rates of emergency department visits and inpatient admissions significantly decreased, and the rate of ambulatory visits significantly increased.

CONCLUSIONS

CSII was associated with significant decreases in antidiabetic drug and healthcare resource utilization, contributing to stability of care. The evidence from this study indicates that CSII should be considered as an option for patients with type 2 diabetes mellitus who are using MDI and are experiencing a high degree of antidiabetic drug and healthcare resource utilization.

Review of the Lynch syndrome: history, molecular genetics, screening, differential diagnosis, and medicolegal ramifications

More than one million patients will manifest colorectal cancer (CRC) this year of which, conservatively, approximately 3% (approximately 30,700 cases) will have Lynch syndrome (LS), the most common hereditary CRC predisposing syndrome. Each case belongs to a family with clinical needs that require genetic counseling, DNA testing for mismatch repair genes (most frequently MLH1 or MSH2) and screening for CRC. Colonoscopy is mandated, given CRC's proximal occurrence (70-80% proximal to the splenic flexure). Due to its early age of onset (average 45 years of age), colonoscopy needs to start by age 25, and because of its accelerated carcinogenesis, it should be repeated every 1 to 2 years through age 40 and then annually thereafter. Should CRC occur, subtotal colectomy may be necessary, given the marked frequency of synchronous and metachronous CRC. Because 40-60% of female patients will manifest endometrial cancer, tailored management is essential. Additional extracolonic cancers include ovary, stomach, small bowel, pancreas, hepatobiliary tract, upper uroepithelial tract, brain (Turcot variant) and sebaceous adenomas/carcinomas (Muir-Torre variant). LS explains only 10-25% of familial CRC.

A prospective randomized trial of cannulation technique in ERCP: effects on technical success and post-ERCP pancreatitis

BACKGROUND AND STUDY AIMS

Inadvertent injection of contrast agent into the pancreatic duct is believed to be an important contributor to pancreatitis occurring after endoscopic retrograde cholangiopancreatography (post-ERCP pancreatitis, PEP). Our aim was to examine whether primary deep biliary cannulation with a guide wire is associated with a lower rate of PEP than conventional contrast-assisted cannulation.

PATIENTS AND METHODS

From August 2003 to April 2006 all patients with an intact papilla who were referred for ERCP were eligible. Patients with pancreatic or ampullary cancer were excluded. Patients were randomized to undergo sphincterotomy biliary cannulation using either contrast injection or a guide wire. The ERCP fellow attempted initially for 5 minutes. If unsuccessful, the consultant attempted for 5 minutes using the same technique, followed by crossover to the other technique in the same sequence and then needle-knife sphincterotomy where appropriate. Patients were assessed clinically after the procedure, then followed up with telephone interviews after 24 hours and 30 days, and serum amylase and lipase tests after 24 hours.

RESULTS

Out of 1654 patients undergoing ERCP, 413 were included in the study. PEP occurred in 29/413 (7.0 %): 16 in the guide-wire arm, 13 in the contrast arm ( P = 0.48). The overall cannulation success rate was 97.3 %. Cannulation was successful without crossover in 323/413 patients (78.2 %): 167/202 (81.4 %) in the guide-wire arm and 156/211 (73.9 %) in the contrast arm ( P = 0.03). Multivariate analysis demonstrated female sex (OR = 2.7, P = 0.04), suspected sphincter of Oddi dysfunction (OR = 5.5, P = 0.01), and complete filling of the pancreatic duct with contrast agent (OR = 3.5, P = 0.02) to be independently associated with PEP. The risk of PEP increased incrementally with each attempt at the papilla (OR 1.4 per attempt, P = 0.04) to greater than 10 % after four or more attempts.

CONCLUSIONS

The guide-wire technique improves the primary success rate for biliary cannulation during ERCP but does not reduce the incidence of PEP compared to the conventional contrast technique. The incidence of PEP increases incrementally with each attempt at the papilla.

Paclitaxel-based chemoradiotherapy in localized gastric carcinoma: degree of pathologic response and not clinical parameters dictated patient outcome

PURPOSE

Preoperative chemoradiotherapy may increase the R0 (curative) resection rate, overall survival (OS) duration, and disease-free survival (DFS) duration. We evaluated paclitaxel-based induction chemotherapy and chemoradiotherapy in patients with localized gastric or gastroesophageal adenocarcinoma to determine its feasibility, impact on the R0 resection rate, type of pathologic response, OS, and DFS.

PATIENTS AND METHODS

Patients with operable, localized gastric, or gastroesophageal adenocarcinoma were eligible. Staging included endoscopic ultrasonography (EUS) and laparoscopy. Patients received two 28-day cycles of induction chemotherapy of fluorouracil, paclitaxel, and cisplatin followed by 45 Gy of radiation and concurrent fluorouracil plus paclitaxel. The cancer was restaged and surgery was attempted. Postsurgery pathologic findings and R0 resection were correlated with OS and DFS.

RESULTS

Forty-one patients were enrolled. Most carcinomas were proximal (83%) and pretreatment stage EUST3 (85%). Forty patients (98%) underwent surgery, and 78% had an R0 resection. We observed a pathologic complete response (pathCR) rate of 20% and a pathologic partial response (pathPR) rate of 15% (< 10% residual cancer cells in the resected specimen). No pretreatment parameter (sex, cancer location, baseline T stage, or baseline N stage) predicted the type of postsurgery pathologic response, OS, or DFS. However, pathCR (P = .02), pathCR + pathPR (P = .006), R0 resection (P < .001), and postsurgery T and N stages (P = .01 and P < .001, respectively) were associated with OS. Same parameters were significantly correlated with DFS. Toxicity was manageable.

CONCLUSION

The type of pathologic response but not pretreatment parameters was associated with OS and DFS. Efforts to increase the rate of pathologic response and better systemic cancer control are warranted.

Multi-institutional trial of preoperative chemoradiotherapy in patients with potentially resectable gastric carcinoma

PURPOSE

In the West, curative (R0) resection is achieved in approximately 50% of patients with localized gastric carcinoma, and more than 60% die of cancer following an R0 resection. A multi-institutional study of preoperative chemoradiotherapy was done to assess the R0 resection rate, pathologic complete response (pathCR) rate, safety, and survival in patients with resectable gastric carcinoma.

PATIENTS AND METHODS

Operable patients with localized gastric adenocarcinoma were eligible. Staging also included a laparoscopy and endoscopic ultrasonography (EUS). Patients received up to two 28-day cycles of induction chemotherapy of fluorouracil, leucovorin, and cisplatin, followed by 45 Gy of radiation plus concurrent fluorouracil. Patients were then staged and surgery was attempted.

RESULTS

Thirty-four patients were registered at three institutions. One ineligible patient was excluded. Most patients had a promixal cancer and EUST3N1 designation. Twenty-eight (85%) of 33 patients underwent surgery. The R0 resection rate was 70% and pathCR rate was 30%. A pathologic partial response (< 10% residual carcinoma in the primary) occurred in eight patients (24%). EUS T plus N and postsurgery T plus N correlation showed significant downstaging (P = <.01). The median survival time for 33 patients was 33.7 months. Patients achieving a pathCR or pathPR had a significantly longer median survival time (63.9 months) than those achieving less than pathPR (12.6 months; P =.03). There were two treatment-related deaths.

CONCLUSION

Our data suggest that the three-step strategy of preoperative induction chemotherapy followed by chemoradiotherapy resulted in substantial pathologic response that resulted in durable survival time. This strategy is worthy of a direct comparison with postoperative adjuvant chemoradiotherapy.

Multi-institutional trial of preoperative chemoradiotherapy in patients with potentially resectable gastric carcinoma

PURPOSE

In the West, curative (R0) resection is achieved in approximately 50% of patients with localized gastric carcinoma, and more than 60% die of cancer following an R0 resection. A multi-institutional study of preoperative chemoradiotherapy was done to assess the R0 resection rate, pathologic complete response (pathCR) rate, safety, and survival in patients with resectable gastric carcinoma.

PATIENTS AND METHODS

Operable patients with localized gastric adenocarcinoma were eligible. Staging also included a laparoscopy and endoscopic ultrasonography (EUS). Patients received up to two 28-day cycles of induction chemotherapy of fluorouracil, leucovorin, and cisplatin, followed by 45 Gy of radiation plus concurrent fluorouracil. Patients were then staged and surgery was attempted.

RESULTS

Thirty-four patients were registered at three institutions. One ineligible patient was excluded. Most patients had a promixal cancer and EUST3N1 designation. Twenty-eight (85%) of 33 patients underwent surgery. The R0 resection rate was 70% and pathCR rate was 30%. A pathologic partial response (< 10% residual carcinoma in the primary) occurred in eight patients (24%). EUS T plus N and postsurgery T plus N correlation showed significant downstaging (P = <.01). The median survival time for 33 patients was 33.7 months. Patients achieving a pathCR or pathPR had a significantly longer median survival time (63.9 months) than those achieving less than pathPR (12.6 months; P =.03). There were two treatment-related deaths.

CONCLUSION

Our data suggest that the three-step strategy of preoperative induction chemotherapy followed by chemoradiotherapy resulted in substantial pathologic response that resulted in durable survival time. This strategy is worthy of a direct comparison with postoperative adjuvant chemoradiotherapy.

Genotype-phenotype correlations in Peutz-Jeghers syndrome

BACKGROUND AND AIMS

Peutz-Jeghers syndrome (PJS) is a dominantly inherited disorder often caused by mutations in STK11. Time to onset of symptoms was characterised for a large collection of individuals with PJS who had been tested for STK11 mutations and genotype-phenotype correlations were evaluated.

METHODS

We characterised mutations in 42 independent probands and also used a historical cohort design to study 51 individuals with Peutz-Jeghers syndrome who had completed self-administered questionnaires.

RESULTS

Mutations were detected in 22/32 (69%) probands with PJS and 0/10 probands referred to rule out PJS. Real-time PCR analysis to quantitate DNA failed to detect any large deletions in PJS participants without STK11 mutations. The median time to onset for gastrointestinal symptoms or polypectomy was 13 years of age but showed a wide variability. Gastric polyps were frequent in PJS participants, with a median age at onset of 16 years. Individuals with missense mutations had a significantly later time to onset of first polypectomy (p = 0.04) and of other symptoms compared with those participants either with truncating mutations or no detectable mutation.

CONCLUSION

STK11 mutation analysis should be restricted to individuals who meet PJS criteria or their close relatives. Direct sequencing of STK11 yields a high rate of point mutations in individuals who meet phenotypic PJS criteria. Individuals with missense mutations of STK11 typically had a later time to onset for PJS symptoms. The common occurrence of gastric polyps may facilitate chemopreventive studies for this disorder.

Significance of post-chemoradiation biopsy in predicting residual esophageal carcinoma in the surgical specimen

Pathologic complete response in the resected esophagus can be achieved in approximately 30% of patients with locally advanced esophageal or gastroesophageal junction carcinoma after preoperative chemoradiation therapy. These patients tend to have a longer survival than those who have less than pathologic complete response. Post-chemoradiation esophageal biopsy (PCEB) is used to check for the presence of residual tumor before a definitive resection is performed, but the clinical significance of PCEB findings is not clear due to the possibility of sampling bias and the superficial nature of the specimen obtained. We evaluated the use of PCEB (defined as biopsy taken within 30 days before esophagectomy) in predicting residual cancer in post-treatment esophagectomy specimens. PCEB was performed in 65 of 183 (36%) patients with locally advanced esophageal or gastroesophageal junction carcinoma, who received preoperative chemoradiation therapy. The cancer status in PCEB was correlated with the residual cancer in the esophagectomy specimens. PCEB had no cancer in 80% (52 of 65) of patients (Bx-negative) and cancer in 20% (13 of 65) of patients (Bx-positive). There was no difference in the presence of residual cancer (either in esophagus or lymph node) in esophagectomy specimens between Bx-negative patients (77%, 40 of 52) or Bx-positive patients (92%, 12 of 13), P = 0.44. The positive predictive value of biopsy was 92% (12 of 13), negative predictive value 23% (12 of 52), sensitivity 23% (12 of 52) and specificity 92% (12 of 13). There was no difference in the residual cancer staging in the esophagectomy specimen between Bx-positive and Bx-negative patients. In contrast, residual metastatic carcinoma in lymph nodes was more frequent in Bx-positive patients (69.2%, 9 of 13) than in Bx-negative patients (28.8%, 15 of 52), P = 0.01. Our data suggest that PCEB is a specific but not a sensitive predictor of residual cancer following esophagectomy. Bx-positive patients tend to have more frequent residual tumor in lymph nodes. The utility of PCEB in predicting residual cancer in the lymph nodes needs to be explored further along with molecular predictors of response to preoperative therapy.

A randomised, double blind, placebo controlled study of celecoxib, a selective cyclooxygenase 2 inhibitor, on duodenal polyposis in familial adenomatous polyposis

BACKGROUND

Non-selective cyclooxygenase (COX) inhibitors (non-steroidal anti-inflammatory drugs) inhibit large bowel carcinogenesis in patients with familial adenomatous polyposis (FAP). Their role in the duodenum of these patients is less certain. The disease modifying activity of specific COX-2 inhibitors has not been explored in humans.

PATIENTS AND METHODS

This was a randomised, double blind, placebo controlled study of celecoxib (100 mg twice daily (n=34) or 400 mg twice daily (n=32)) versus placebo (n=17), given orally twice daily for six months to patients with FAP. Efficacy was assessed qualitatively by blinded review of shuffled endoscopy videotapes comparing the extent of duodenal polyposis at entry and at six months and quantitatively by measurement of the percentage change in duodenal area covered by discrete and plaque-like adenomas from photographs of high and low density polyposis.

RESULTS

Shuffled and blinded video review showed a statistically significant effect of 400 mg twice daily celecoxib compared with placebo treatment (p=0.033) with all five independent observers scoring a beneficial effect. Overall, patients taking celecoxib 400 mg twice daily showed a 14.5% reduction in involved areas compared with a 1.4% for placebo (p=0.436). However, patients with clinically significant disease at baseline (greater than 5% covered by polyps) showed a 31% reduction in involved areas with celecoxib 400 mg twice daily compared with 8% on placebo (p=0.049).

CONCLUSIONS

A panel of five endoscopists found a significant reduction in duodenal polyposis after six months of treatment with celecoxib 400 mg twice daily. COX-2 inhibition may help this otherwise untreatable condition.

A three-step strategy of induction chemotherapy then chemoradiation followed by surgery in patients with potentially resectable carcinoma of the esophagus or gastroesophageal junction

BACKGROUND

Patients with locoregional carcinoma of the esophagus or gastroesophageal junction have a poor survival rate after surgery. Preoperative chemotherapy or chemoradiotherapy has not improved the outcome for these patients. Our study was designed to assess the feasibility of preoperative induction combination chemotherapy in addition to chemoradiotherapy to improve the curative resection rate, local control, and survival. PATIENTS AND METHODS Patients having histologic proof of localized carcinoma (either squamous cell carcinoma or adenocarcinoma) of the esophagus or gastroesophageal junction underwent full classification including endoscopic ultrasonography (EUS). Patients first received up to two courses of induction chemotherapy consisting of 5-fluorouracil at 750 mg/m(2)/day as continuous infusion on Days 1--5, cisplatin at 15 mg/m(2)/day as an intravenous bolus on Days 1--5, and paclitaxel at 200 mg/m(2) as a 24-hour intravenous infusion on Day 1. The second course was repeated on Day 29. This was followed by radiotherapy (45 grays in 25 fractions) and concurrent admission of 5-fluorouracil (300 mg/m(2)/day as a continuous infusion 5 days/week) and cisplatin (20 mg/m(2) on Days 1--5 of radiotherapy). After chemoradiotherapy, patients underwent surgery. The feasibility of this approach, curative resection rates, patient survival, and patterns of failure were assessed.

RESULTS

Thirty-seven of 38 patients enrolled were evaluable for toxicity and survival. Adenocarcinoma and distal esophageal location of carcinoma were observed frequently. Thirty-five (95%) of the 37 patients underwent surgery, all of whom had an R0 (curative) resection. A pathologic complete response was noted in 11 (30%) of the 37 total patients. In addition, 5 patients (14%) had only microscopic carcinoma. According to EUS classification, 31 (89%) of the 35 patients who underwent surgery had a T3 carcinoma whereas according to pathologic classification only 3 (9%) had a T3 carcinoma (P </= 0.01). Similarly, according to EUS classification, 23 patients (66%) had an N1 carcinoma, whereas according to pathologic classification only 7 patients (20%) had an N1 carcinoma (P < or = 0.01). At a median follow-up of 20 months (minimum follow-up, 13+ months; maximum follow-up, 36+ months), the median survival duration for the 37 patients had not yet been reached. In addition, there were two deaths related to surgery.

CONCLUSIONS

These data show that the three-step strategy of preoperative paclitaxel-based induction chemotherapy then chemoradiotherapy followed by surgery is feasible and appears quite active in patients having locoregional carcinoma of the esophagus or gastroesophageal junction. Future investigations should focus on substituting cisplatin with less toxic agents and including more systemic therapy with newer classes of agents.

A three-step strategy of induction chemotherapy then chemoradiation followed by surgery in patients with potentially resectable carcinoma of the esophagus or gastroesophageal junction

BACKGROUND

Patients with locoregional carcinoma of the esophagus or gastroesophageal junction have a poor survival rate after surgery. Preoperative chemotherapy or chemoradiotherapy has not improved the outcome for these patients. Our study was designed to assess the feasibility of preoperative induction combination chemotherapy in addition to chemoradiotherapy to improve the curative resection rate, local control, and survival. PATIENTS AND METHODS Patients having histologic proof of localized carcinoma (either squamous cell carcinoma or adenocarcinoma) of the esophagus or gastroesophageal junction underwent full classification including endoscopic ultrasonography (EUS). Patients first received up to two courses of induction chemotherapy consisting of 5-fluorouracil at 750 mg/m(2)/day as continuous infusion on Days 1--5, cisplatin at 15 mg/m(2)/day as an intravenous bolus on Days 1--5, and paclitaxel at 200 mg/m(2) as a 24-hour intravenous infusion on Day 1. The second course was repeated on Day 29. This was followed by radiotherapy (45 grays in 25 fractions) and concurrent admission of 5-fluorouracil (300 mg/m(2)/day as a continuous infusion 5 days/week) and cisplatin (20 mg/m(2) on Days 1--5 of radiotherapy). After chemoradiotherapy, patients underwent surgery. The feasibility of this approach, curative resection rates, patient survival, and patterns of failure were assessed.

RESULTS

Thirty-seven of 38 patients enrolled were evaluable for toxicity and survival. Adenocarcinoma and distal esophageal location of carcinoma were observed frequently. Thirty-five (95%) of the 37 patients underwent surgery, all of whom had an R0 (curative) resection. A pathologic complete response was noted in 11 (30%) of the 37 total patients. In addition, 5 patients (14%) had only microscopic carcinoma. According to EUS classification, 31 (89%) of the 35 patients who underwent surgery had a T3 carcinoma whereas according to pathologic classification only 3 (9%) had a T3 carcinoma (P </= 0.01). Similarly, according to EUS classification, 23 patients (66%) had an N1 carcinoma, whereas according to pathologic classification only 7 patients (20%) had an N1 carcinoma (P < or = 0.01). At a median follow-up of 20 months (minimum follow-up, 13+ months; maximum follow-up, 36+ months), the median survival duration for the 37 patients had not yet been reached. In addition, there were two deaths related to surgery.

CONCLUSIONS

These data show that the three-step strategy of preoperative paclitaxel-based induction chemotherapy then chemoradiotherapy followed by surgery is feasible and appears quite active in patients having locoregional carcinoma of the esophagus or gastroesophageal junction. Future investigations should focus on substituting cisplatin with less toxic agents and including more systemic therapy with newer classes of agents.

COX-2 inhibition in clinical cancer prevention

Colorectal cancer is an excellent model for studying cancer prevention by means of secondary (e.g., polypectomy to remove a precursor adenoma) and primary (chemoprevention) strategies. Evidence has shown that regular users of aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) have a reduction in risk of colorectal cancer. A possible mechanism of this benefit is decreased prostaglandin production, which is achieved through inhibition of cyclooxygenase (COX) activity, and possibly other pathways. Two isoforms of COX--COX-1 and COX-2--have been identified. COX-2 is expressed in colorectal adenomas and carcinomas, both in humans and rodents. Inhibition of COX-2 has been shown to decrease the incidence of carcinogen-induced neoplasia in rats and to lower the incidence of adenomas in murine models. Several COX-2 inhibitors, with the potential for less toxicity than that associated with traditional NSAIDs, are under development. This paper reviews potential chemoprevention of colorectal cancer using COX-2 inhibitors in patients at increased risk, e.g., patients with familial adenomatous polyposis, hereditary nonpolyposis colorectal cancer, and sporadic adenomas. Included are the rationale for use of such agents, results of a study showing a significant reduction in adenoma burden in familial adenomatous polyposis patients who received the selective COX-2 inhibitor celecoxib (Celebrex), and the design of other ongoing or planned clinical trials.

Age-associated risk of cancer among individuals with N-acetyltransferase 2 (NAT2) mutations and mutations in DNA mismatch repair genes

Mutations in N-acetyltransferase 2 (NAT2), a highly polymorphic enzyme involved in the metabolism of xenobiotics and carcinogens, may affect risk for colorectal cancer (CRC), especially among individuals with germ-line mutations in DNA mismatch repair genes. We determined the NAT2 genotypes and allele frequencies for 86 individuals with CRC who had mutations in hMLH1, hMSH2, or hPMS1. No significant difference in time to onset was observed between rapid (NAT2*4) and slow (NAT2*5, NAT2*6, and NAT2*7) acetylators. However, when individuals were stratified separately by NAT2 polymorphism (NAT2*5, NAT2*6, and NAT2*7), those who were heterozygous at the mutant locus NAT2*7 after adjustment for the NAT2 mutant loci NAT2*5 and NAT2*6 had a significantly higher risk of CRC (hazard ratio, 2.96; P = 0.012) and all of the cancers (hazard ratio, 3.37; P = 0.00004) than individuals homozygous for wild type at the NAT2*7 allele. These findings suggest that NAT2 genotype may be an important factor in tumorigenesis of CRC and cancers related to hereditary nonpolyposis CRC among individuals with mismatch repair defects.

Phase I study of irinotecan and concurrent radiation therapy for upper GI tumors

Irinotecan (Camptosar) is an active chemotherapeutic agent for lung, gastric, esophageal, and colorectal cancers and a potent radiosensitizer. This phase I study was designed to assess the maximum tolerated dose of weekly irinotecan combined with concurrent radiotherapy for patients with locally advanced, unresectable gastric, gastroesophageal junction, or esophageal cancer. Patients who received previous chemotherapy (excluding irinotecan) or who experienced recurrent cancer after surgery were eligible for this protocol. The total dose of radiation did not exceed 50.4 Gy (28 fractions of 1.8 Gy each). The starting dose level of irinotecan was 30 mg/m2 infused over 90 minutes given weekly for 5 weeks. Subsequent dose levels were increased in 10 mg/m2 increments to 40, 50, 60, and 70 mg/m2. Of 15 patients who have been enrolled to date, all are evaluable for toxicities and 12 for response. Major hematologic toxicities (grade 3/4) were neutropenia, chills, hemorrhage, and anemia. Grade 3/4 gastrointestinal toxicities included nausea, vomiting, dehydration, anorexia, and constipation. Other severe nonhematologic toxicities included fatigue, hypotension, and hypothermia, as well as cardiovascular toxicities. There was no severe diarrhea and no treatment-related deaths. Of the 12 evaluable patients, 7 (58%) responded, including 2 complete responses; 4 (30%) had no change and 1 had progressive disease. Survival ranged from 1 month to 15 months, with a median survival of 8 months. When the total dose of irinotecan given concurrently with radiotherapy was higher than 250 mg/m2, patients experienced significantly more severe grade 3/4 toxicities than with lower doses (P = .04), with no improvement in response rate. It was concluded that weekly doses of irinotecan of up to 60 mg/m2 with concurrent radiotherapy given over 5 weeks was feasible and demonstrated good response. This regimen did not cause severe diarrhea or pneumonitis, but neutropenia and fatigue were major toxicities. The study continues to accrue.

Inactivation of germline mutant APC alleles by attenuated somatic mutations: a molecular genetic mechanism for attenuated familial adenomatous polyposis

Germline mutations of the adenomatous polyposis coli (APC) tumor-suppressor gene result in familial adenomatous polyposis (FAP). Patients with FAP typically develop hundreds to thousands of benign colorectal tumors and early-onset colorectal cancer. A subset of germline APC mutations results in an attenuated FAP (AFAP) phenotype, in which patients develop fewer tumors and develop them at an older age. Although a genotype-phenotype correlation between the locations of APC germline mutations and the development of AFAP has been well documented, the mechanism for AFAP has not been well defined. We investigated the mechanism for AFAP in patients carrying a mutant APC allele (APC(AS9)) that has a mutation in the alternatively spliced region of exon 9. APC(AS9) was found to down-regulate beta-catenin-regulated transcription, the major tumor-suppressor function of APC, as did the wild-type APC. Mutation analysis showed that both APC(AS9) and the wild-type APC alleles were somatically mutated in most colorectal tumors from these patients. Functional analysis showed that 4666insA, a common somatic mutation in APC(AS9) in these tumors, did not inactivate the wild-type APC. Our results indicate that carriers of APC(AS9) develop fewer colorectal tumors than do typical patients with FAP because somatic inactivation of both APC alleles is necessary for colorectal tumorigenesis. However, these patients develop colorectal tumors more frequently than does the general population because APC(AS9) is inactivated by mutations that do not inactivate the wild-type APC.

The effect of celecoxib, a cyclooxygenase-2 inhibitor, in familial adenomatous polyposis

BACKGROUND

Patients with familial adenomatous polyposis have a nearly 100 percent risk of colorectal cancer. In this disease, the chemopreventive effects of nonsteroidal antiinflammatory drugs may be related to their inhibition of cyclooxygenase-2.

METHODS

We studied the effect of celecoxib, a selective cyclooxygenase-2 inhibitor, on colorectal polyps in patients with familial adenomatous polyposis. In a double-blind, placebo-controlled study, we randomly assigned 77 patients to treatment with celecoxib (100 or 400 mg twice daily) or placebo for six months. Patients underwent endoscopy at the beginning and end of the study. We determined the number and size of polyps from photographs and videotapes; the response to treatment was expressed as the mean percent change from base line.

RESULTS

At base line, the mean (+/-SD) number of polyps in focal areas where polyps were counted was 15.5+/-13.4 in the 15 patients assigned to placebo, 11.5+/-8.5 in the 32 patients assigned to 100 mg of celecoxib twice a day, and 12.3+/-8.2 in the 30 patients assigned to 400 mg of celecoxib twice a day (P=0.66 for the comparison among groups). After six months, the patients receiving 400 mg of celecoxib twice a day had a 28.0 percent reduction in the mean number of colorectal polyps (P=0.003 for the comparison with placebo) and a 30.7 percent reduction in the polyp burden (the sum of polyp diameters) (P=0.001), as compared with reductions of 4.5 and 4.9 percent, respectively, in the placebo group. The improvement in the extent of colorectal polyposis in the group receiving 400 mg twice a day was confirmed by a panel of endoscopists who reviewed the videotapes. The reductions in the group receiving 100 mg of celecoxib twice a day were 11.9 percent (P=0.33 for the comparison with placebo) and 14.6 percent (P=0.09), respectively. The incidence of adverse events was similar among the groups.

CONCLUSIONS

In patients with familial adenomatous polyposis, six months of twice-daily treatment with 400 mg of celecoxib, a cyclooxygenase-2 inhibitor, leads to a significant reduction in the number of colorectal polyps.

Mutation of hMSH3 and hMSH6 mismatch repair genes in genetically unstable human colorectal and gastric carcinomas

Mutations within microsatellite sequences, consisting of additions or deletions of repeat units, are known as the replication/repair error positive (RER+) phenotype or micorsatellite instability (MI). Microsatellite instability has been demonstrated in hereditary and sporadic colorectal carcinomas and is usually observed in noncoding regions of genomic DNA. However, relatively few coding region targets of MI have been identified thus far. Using PCR, we amplified regions encompassing (A)8 and (C)8 microsatellite tracts within hMSH3 and hMSH6 from 31 RER+ sporadic colorectal tumors, 8 hereditary colon cancers, 23 RER+ gastric carcinomas, and 32 RER- gastric tumors. Mutations were found in 11 (36%) of 31 sporadic colon carcinomas, 4 (50%) of 8 hereditary colorectal cancers, and 5 (22%) of 23 RER+ gastric carcinomas, but in only 2 (6%) of 32 RER- gastric carcinomas. These frameshift mutations cause premature stop codons downstream that are predicted to abolish normal protein function. Our results and those of others suggest that DNA mismatch repair genes, such as hMSH3 and hMSH6, are targets for the mutagenic activity of upstream mismatch repair gene mutations and that this enhanced genomic instability may accelerate the accumulation of mutations in RER+ tumors.

Colitis associated with docetaxel-based chemotherapy in patients with metastatic breast cancer

BACKGROUND

Docetaxel and vinorelbine as combined treatment for metastatic breast cancer can have the dose-limiting toxic effects of mucositis and neutropenic fever. We report unexpected ischaemic colitis in six patients associated with docetaxel-based therapy, three of whom were treated in a phase I study designed to establish the maximum tolerated dose of this combination with the prophylactic use of granulocyte-colony-stimulating factor.

METHODS

Between August, 1997, and December, 1998, 14 patients with metastatic breast cancer were treated with vinorelbine, docetaxel, and granulocyte-colony-stimulating factor in a phase I study. Three patients developed colitis similar to that seen in typhlitis. Three additional patients were identified during scheduled review of toxic effects in patients participating in clinical trials involving docetaxel.

FINDINGS

Three patients on combined vinorelbine and docetaxel developed colitis-like symptoms. Two patients died, one from necrotic bowel and the other from neutropenic fever and colitis. Two of the patients presented on day 7 and day 8 of chemotherapy, respectively, with neutropenic fever and abdominal pain; the third patient developed neutropenia without fever and abdominal pain on day 8. The other three patients were treated with docetaxel, docetaxel and pamidronate disodium, or docetaxel and cyclophosphamide. All three patients presented with abdominal pain on days 10, 5, and 4, respectively. One had non-neutropenic fever, another had neutropenic fever, and the third was afebrile and non-neutropenic at the time of presentation with abdominal pain. Three patients had blood in their diarrhoea, abdominal tenderness, or both. Computed tomography of the abdomen and pelvis showed features of colitis in three patients.

INTERPRETATION

This serious complication may result from the use of docetaxel and may be exacerbated by its combination with vinorelbine. Study of hospital-based patients treated with taxane-based chemotherapy is underway to find out the frequency of such complications.

Effects of cyclin D1 polymorphism on age of onset of hereditary nonpolyposis colorectal cancer

A common polymorphism in the cyclin D1 gene enhances the gene's alternate splicing. The alternatively spliced product encodes an altered protein that does not contain sequences involved in the turnover of the protein. We found that hereditary nonpolyposis colorectal carcinoma patients who were homozygous or heterozygous for the mutant allele developed colorectal cancer an average of 11 years earlier than patients who were homozygous for the normal alleles. This is the first report indicating that the cyclin D1 polymorphism influences age of onset of cancer. Because cyclin D1 plays an important role in the G1 to S phase transition of the cell cycle, our findings suggest that cells with the mutant allele accumulate mutations as a result of defective mismatch repair and may also bypass the G1-S checkpoint of the cell cycle more easily than in cells not carrying the polymorphism. The polymorphism has a dominant phenotype.

Genomic rearrangements of the APC tumor-suppressor gene in familial adenomatous polyposis

Germline mutations of the adenomatous polyposis coli (APC) tumor-suppressor gene result in the hereditary colorectal cancer syndrome familial adenomatous polyposis (FAP). Almost all APC mutations that have been identified are single-nucleotide alterations, small insertions, or small deletions that would truncate the protein product of the gene. No well-characterized intragenic rearrangement of APC has been described, and the prevalence of this type of mutation in FAP patients is not clear. We screened 49 potential FAP families and identified 26 different germline APC mutations in 30 families. Four of these mutations were genomic rearrangements resulting from homologous and nonhomologous recombinations mediated by Alu elements. Two of these four rearrangements were complex, involving deletion and insertion of nucleotides. Of these four rearrangements, one resulted in the deletion of exons 11 and 12 and two others resulted in either complete or partial deletion of exon 14. The fourth rearrangement grossly altered the sequence within intron 14. Although this rearrangement did not affect any coding sequence of APC at the genomic DNA level, it caused inappropriate splicing of exon 14. These rearrangements were initially revealed by analyzing cDNAs and could not have been identified by using mutation detection methods that screened each exon individually. The identification of a rearrangement that did not alter any coding exons yet affected the splicing further underscores the importance of using cDNA for mutation analysis. The identification of four genomic rearrangements among 30 mutations suggests that genomic rearrangements are frequent germline APC mutations.

Reduced expression of cyclooxygenase 2 proteins in hereditary nonpolyposis colorectal cancers relative to sporadic cancers

BACKGROUND & AIMS

Cyclooxygenase (COX) enzymes catalyze the conversion of arachidonic acid to prostaglandins. Evidence suggests that nonsteroidal anti-inflammatory drugs reduce the risk of colorectal cancer (CRC) and that this effect is mediated through COX inhibition. We analyzed and compared expression of the inducible COX-2 isoform in colorectal neoplasms from patients with hereditary nonpolyposis colorectal cancer (HNPCC), familial adenomatous polyposis (FAP), and sporadic CRC. Given that COX-2 is induced by transforming growth factor (TGF)-beta and that TGF-beta type II receptor (RII) mutations are found in HNPCCs, we determined the relationship between RII status and COX-2 expression.

METHODS

COX-2 protein expression was determined in colorectal epithelia using immunohistochemistry and Western blotting. Patients with HNPCC had known mutations in hMLH1 or hMSH2 genes and/or met the Amsterdam criteria. In CRCs from HNPCC cases, mutations were sought in the coding region of the RII gene using the polymerase chain reaction.

RESULTS

COX-2 was detected in adenomas from 2 of 3 HNPCC, 6 of 7 FAP, and 5 of 8 sporadic cases. In CRCs, COX-2 staining was found in 16 of 24 (67%) HNPCC vs. 24 of 26 (92%) sporadic cases (P = 0.035) and in 2 of 2 FAP cases. Staining intensity was reduced in HNPCCs compared with sporadic CRCs (P = 0.035). Staining localized to the cytoplasm of neoplastic cells; normal epithelial cells were negative for COX-2. Overexpression of COX-2 in CRCs relative to normal mucosa was confirmed by Western blotting. TGF-beta RII mutations were detected in 12 of 14 HNPCCs examined, including 3 of 4 COX-2-negative and 9 of 10 COX-2-positive cancers.

CONCLUSIONS

The frequency and intensity of COX-2 expression was significantly reduced in HNPCCs relative to sporadic CRCs, and was not a consequence of RII mutations. Given that many HNPCCs express COX-2, inhibition of this enzyme may be an important strategy to prevent CRC in these patients.

Enhanced staging and all chemotherapy preoperatively in patients with potentially resectable gastric carcinoma

PURPOSE

Patients with local-regional gastric carcinoma have a low rate of curative resection (R0) because of the advanced stage at diagnosis and suboptimal clinical staging. This study was designed to improve clinical staging with the use of laparoscopy and endoscopic ultrasonography (EUS) and to improve R0 resection rates and tolerance by delivering all chemotherapy preoperatively in patients with potentially resectable gastric carcinoma.

PATIENTS AND METHODS

All patients with histologic proof of localized adenocarcinoma of the stomach underwent a staging laparoscopy before registration. EUS was performed when feasible. The intention was to administer up to five courses of preoperative chemotherapy consisting of fluorouracil (500 mg/m(2)/d as a continuous infusion on days 1 through 5 and as a bolus on days 12 and 19), interferon alfa-2b (3 million units subcutaneously three times a week for 3 weeks), and cisplatin (15 mg/m(2)/d as a bolus on days 1 through 5). After chemotherapy, surgery was attempted to remove the primary and regional lymph nodes. Clinical response and EUS staging were correlated with surgical pathology. The feasibility of this approach, resection rates, patient survival, and patterns of failure also were assessed.

RESULTS

All 30 patients enrolled were assessed for toxicity, response, and survival. Nineteen men and 11 women were enrolled. The median number of courses delivered per patient was three (range, one to five courses). Fourteen patients (47%) received all five preoperative courses of chemotherapy. The overall clinical response rate was 34%. Twenty-nine patients (97%) underwent attempted resection. Twenty-five (83%) had an R0 resection. Two patients (7%) had no evidence of carcinoma in the surgical specimen, and three had only microscopic carcinoma (>/= 90% necrosis). Posttreatment EUS findings did not correlate well with surgical pathology. The median duration of follow-up was 30 months (range, 5 months to 65+ months). The median survival time for 30 patients, calculated by the Kaplan-Meier method, was 30 months (range, 5 months to 65+ months). There were no cases of grade 4 toxicity.

CONCLUSION

It is feasible to administer prolonged preoperative therapy in patients with potentially resectable gastric carcinoma. Enhanced staging with laparoscopy and EUS helped in proper selection of patients and better characterization of the stage.

Antibiotic treatment of gastric lymphoma of mucosa-associated lymphoid tissue. An uncontrolled trial

BACKGROUND

Gastric lymphoma of mucosa-associated lymphoid tissue (MALT) is related to Helicobacter pylori infection and may depend on this infection for growth.

OBJECTIVE

To determine the response of gastric MALT lymphoma to antibiotic treatment.

DESIGN

Prospective, uncontrolled treatment trial.

SETTING

University hospital referral center and three collaborating university and community hospitals.

PATIENTS

34 patients with stage I or stage II N1 gastric MALT lymphoma.

INTERVENTION

Two of three oral antibiotic regimens--1) amoxicillin, 750 mg three times daily, and clarithromycin, 500 mg three times daily; 2)tetracycline, 500 mg four times daily, and clarithromycin, 500 mg three times daily; or 3) tetracycline, 500 mg four times daily, and metronidazole, 500 mg three times daily--were administered sequentially (usually in the order written) for 21 days at baseline and at 8 weeks, along with a proton-pump inhibitor (lansoprazole or omeprazole) and bismuth subsalicylate.

MEASUREMENTS

Complete remission was defined as the absence of histopathologic evidence of lymphoma on endoscopic biopsy. Partial remission was defined as a reduction in endoscopic tumor stage or 50% reduction in the size of large tumors.

RESULTS

34 patients were followed for a mean (+/-SD) of 41 +/- 16 months (range, 18 to 70 months) after antibiotic treatment. Of 28 H. pylori-positive patients, 14 (50% [95% CI, 31% to 69%]) achieved complete remission, 8 (29%) achieved partial remission (treatment eventually failed in 4 of the 8), and 10 (36% [CI, 19% to 56%]) did not respond to treatment. Treatment failed in all 6 (100% [CI, 54% to 100%]) H. pylori-negative patients. Patients with endoscopic appearance of gastritis (stage I T1 disease) were most likely to achieve complete remission within 18 months. Tumors in the distal stomach were associated with more favorable response than tumors in the proximal stomach.

CONCLUSIONS

A subset of H. pylori-positive gastric MALT lymphomas, including infiltrative tumors, may respond to antibiotics. The likelihood of early complete remission seems to be greatest for superficial and distal tumors.

Tumor downstaging and sphincter preservation with preoperative chemoradiation in locally advanced rectal cancer: the M. D. Anderson Cancer Center experience

PURPOSE

To evaluate the rates of tumor downstaging after preoperative chemoradiation for locally advanced rectal cancer.

MATERIALS AND METHODS

Preoperative chemoradiotherapy (CTX/XRT) that delivered 45 Gy in 25 fractions over 5 weeks with continuous infusion 5-fluorouracil (300 mg/m2/day) was given to 117 patients. The pretreatment stage distribution, as determined by endorectal ultrasound (u), included uT2N0 in 2%, uT3N0 in 47%, uT3N1 in 49%, and uT4N0 in 2% of cases; endorectal ultrasound was not performed in 13% of cases (15 patients). Approximately 6 weeks after completion of CTX/XRT, surgery was performed.

RESULTS

The pathological tumor stages were Tis-2N0 in 26%, T2N1 in 5%, T3N0 in 21%, T3N1 in 15%, T4N0 in 5%, and T4NI in 1%; a complete response (CR) to preoperative CTX/XRT was pathologically confirmed in 32 (27%) of patients. Tumor downstaging occurred in 72 (62%) cases. Only 3% of cases had pathologic evidence of progressive disease. Pretreatment tumor size (< 5 cm vs. > or = 5 cm) was the only factor predictive of tumor downstaging (p < 0.04). A decrease of > 1 T-stage level was accomplished in 45% of those downstaged. Overall, a sphincter-saving (SP) procedure was possible in 59% of patients and an abdominoperineal resection (APR) was required in 41 % of cases. Factors predictive of SP included downstaging (p < 0.03), age > 40 years (p < 0.007), pretreatment tumor distance, 3 to 6 cm from the anal verge (p < 0.00001), tumor size <6 cm (p < 0.02), mobility (p < 0.004), tumor stage <T4 (p < 0.01), and uN negative (p < 0.008). SP was performed in 23 patients (72%) with a CR and in 48 (67%) of downstaged cases. Among the 69 tumors located < 6 cm from the anal verge, 29 (42%) were resected with a SP. The level of response was important for tumors located < 6 cm from the anal verge because a SP was performed in 9 of the 17 (53%) CRs in this group while only 20 of 52 patients (38%) had a SP when residual disease was present after CTX/XRT. For tumors located > 6 cm from the anal verge, SP was performed in 14 of the 15 (93%) patients with a CR and 32 of 33 (97%) of patients with residual disease (p < 0.00004).

CONCLUSIONS

Significant tumor downstaging results from preoperative chemoradiation allowing sphincter sparing surgery in over 40% of patients whose tumors were located < 6 cm from the anal verge and who otherwise would have required colostomy.

Prognostic implications of response to preoperative infusional chemoradiation in locally advanced rectal cancer

BACKGROUND AND PURPOSE

To evaluate the influence of response to preoperative infusional chemoradiation on outcome parameters among patients with locally advanced rectal cancer.

MATERIALS AND METHODS

Preoperative chemoradiotherapy, 45 Gy in 25 fractions over 5 weeks with continuous infusion 5-fluorouracil (300 mg/m2 per day), was given to 117 patients. As determined by pretreatment endorectal ultrasound (EUS), 96% of cases were Stage T3, and 51% had EUS evidence of perirectal adenopathy. Surgery was performed approximately 6 weeks after chemoradiation therapy. Postoperatively adjuvant systemic therapy, consisting of 400-425 mg/m2 of 5-fluorouracil plus 20 mg/m2 leucovorin for 5 days, was administered every 28 days for six cycles. Outcome parameters of local control (LC), freedom from distant metastases (DMC), disease-free survival (DFS) and cancer specific survival (CSS) were evaluated relative to primary tumor characteristics.

RESULTS

The final post-treatment pathological tumor stages were complete response in 27%, Tis-2 N0 in 26%, T2 N1 in 5%, T3 N0 in 21%, T3 N1 in 15%, T4 N0 in 5% and T4 N1 in 1%. Down-staging occurred in 61% of cases. The pretreatment primary tumor size only influenced rates of local control (P < 0.03) and had no other influence on outcome parameters. Pretreatment evidence of perirectal lymph node involvement had no impact on outcome parameters. Pathologic evidence of nodal involvement did affect DMC (P < 0.002) and DFS (P < 0.003). Pathologic evidence of response did influence freedom from the development of distant metastases (P < 0.004). On pairwise analysis this relationship held only when responders were compared to non-responders. No difference was observed based on the level of downstaging at the primary tumor. Correspondingly, DFS was improved when non-responders were compared to downstaged patients (P < 0.01). Response to preoperative chemoradiation failed to affect rates of LC or CSS. For the group as a whole, adjuvant chemotherapy improved only CSS (P < 0.03). Adjuvant chemotherapy was given to 74 patients, 36 of whom had responded to preoperative chemoradiation. Improvements were only seen in DFS (P < 0.03) when down-staged patients were compared to the non-responders who received adjuvant chemotherapy. In addition, the DFS rates were lower in the non-responder group who received adjuvant chemotherapy even when they were compared to down-staged patients who did not receive adjuvant chemotherapy (P < 0.04).

CONCLUSION

Consistent with other reports, disease free survival and subsequent development of distant metastases is reduced in the more than 60% of patients who respond to preoperative infusional chemoradiation. Evidence of response appears more significant than the degree of response. At present, no impact is seen on cancer specific survival rates. Consideration should be given for strategies that base selection of subsequent adjuvant chemotherapy on response to preoperative chemoradiation.

Loci for efficient detection of microsatellite instability in hereditary non-polyposis colorectal cancer

Most hereditary non-polyposis colorectal cancer (HNPCC) is due to germline mutations in DNA mismatch repair genes. Tumors arising as a result of these mutations display instability in microsatellites, which are short tandem repeats of DNA that are distributed throughout the genome. Although a subset of sporadic colorectal carcinomas also have microsatellite instability (MSI), the phenotype is a useful screening test in identifying patients with HNPCC caused by mutations in mismatch repair (MMR) genes. Studies have shown that some microsatellite markers are more efficient than others in identifying tumors with MSI. Furthermore, the frequency of instability can be assessed by categorizing patients into high (MSI-H, >/= 30-40% positive markers), low (MSI-L), and microsatellite stable (MSS) groups. Using a panel of 28 microsatellite markers, tumor and normal DNA from 10 HNPCC patients was used to identify the five most efficient markers for detecting MSI (BAT26, D2S123, FGA, D18S35, and TP53-DI). Each of the five markers detected MSI in 80-100% of the cases examined. We then expanded the sample size to 17 tumors from HNPCC patients. Each case had evidence for a mutation in either hMSH2 or hMLH1. We compared the efficiency of our panel of five best markers with another panel of five markers (BAT25, BAT26, D2S123, D17S250, and D5S346) identified as being efficient markers for detection of MSI at a recent NCI workshop. Our five selected markers were more efficient (85% vs. 79%) in detecting MSI. However, using either panel, 100% of the cases fell into the MSI-H category and the probability of misclassifying an MSI-H case as MSI-L is very low (0.002-0.008). We also examined four cases meeting the Amsterdam criteria for HNPCC, but with no evidence for mutation in either the hMSH2 or hMLH1 gene. With our panel, three were classified as MSI-H, while only two were classified as such with the NCI reference panel. The probability of misclassifying an MSI-L case as an MSI-H, using a panel of five markers is high (0.263).

Mutation of hMSH3 and hMSH6 mismatch repair genes in genetically unstable human colorectal and gastric carcinomas

Mutations within microsatellite sequences, consisting of additions or deletions of repeat units, are known as the replication/repair error positive (RER+) phenotype or micorsatellite instability (MI). Microsatellite instability has been demonstrated in hereditary and sporadic colorectal carcinomas and is usually observed in noncoding regions of genomic DNA. However, relatively few coding region targets of MI have been identified thus far. Using PCR, we amplified regions encompassing (A)8 and (C)8 microsatellite tracts within hMSH3 and hMSH6 from 31 RER+ sporadic colorectal tumors, 8 hereditary colon cancers, 23 RER+ gastric carcinomas, and 32 RER- gastric tumors. Mutations were found in 11 (36%) of 31 sporadic colon carcinomas, 4 (50%) of 8 hereditary colorectal cancers, and 5 (22%) of 23 RER+ gastric carcinomas, but in only 2 (6%) of 32 RER- gastric carcinomas. These frameshift mutations cause premature stop codons downstream that are predicted to abolish normal protein function. Our results and those of others suggest that DNA mismatch repair genes, such as hMSH3 and hMSH6, are targets for the mutagenic activity of upstream mismatch repair gene mutations and that this enhanced genomic instability may accelerate the accumulation of mutations in RER+ tumors.

Fine mapping of a genetic locus for Peutz-Jeghers syndrome on chromosome 19p

Peutz-Jeghers syndrome (PJS) was recently mapped in a single report to the telomeric region of chromosome 19p (A. Hemminki et al., Nat. Genet., 15: 87-90, 1997). Our studies confirm this location and provide further localization of the PJS locus. In the five families examined, there were no recombinants with the marker D19S886. The multipoint log odds score at D19S886 is 7.52, and we found no evidence for genetic heterogeneity. We also found that all carriers expressed the PJS phenotype and no noncarriers displayed PJS sequellae, indicating complete penetrance with no sporadic cases.

S phase determination in intact colonic crypts by histone H3 messenger RNA in situ hybridization and confocal microscopy

Proliferating cells have a restricted three-dimensional spatial distribution within the crypt, which is the proliferative unit of the colon. Accurate quantitative and spatial analyses of S phase cells in the colon have therefore been limited by histological techniques. To overcome these limitations, S phase cells in microdissected intact colonic crypts of control, modified-starved, and refed rats were labeled by histone H3 in situ hybridization and analyzed by confocal microscopy. High-resolution digital images of the crypt cell nuclei stained with cyanine nucleic acid and of the labeled S phase cells were produced from confocal microscopic optical crypt sections. The S phase labeling index (LI) per whole crypt significantly (P < 0.001) discriminated the proliferative differences between control, modified-starved, and refed rats and correlated (r = 0.92) with the LI determined from histological crypt sections of the same rats. The variance component of the LI attributable to differences between whole crypts, 0.44 (95% confidence interval, 0.38-0.51), was considerably smaller than that attributable to differences between histological crypt sections, 6.07 (95% confidence interval, 5.18-6.96). Confocal microscopy and histone H3 in situ hybridization of intact three-dimensional crypts enables precise in vitro quantitation and spatial analysis of the total and S phase crypt cells.

Correlates of psychologic distress in colorectal cancer patients undergoing genetic testing for hereditary colon cancer

In this article the authors describe the demographic and psychosocial correlates of 2 measures of psychologic distress among 200 colorectal cancer patients undergoing genetic testing for hereditary nonpolyposis colon cancer. The prevalence of symptoms of depression on the Center for Epidemiologic Studies Depression (CES-D) Scale was 24%. In multivariate analysis, female sex, less formal education, fewer sources of social contacts, and less satisfaction with them were associated with high scores on the CES-D Scale. Characteristics associated with high scores on the State-Trait Anxiety Inventory were younger age, less formal education, non-White race, local-regional stage of disease, fewer social contacts, and less satisfaction with them. Information on psychosocial correlates of psychologic distress may prove useful in guiding genetic counseling sessions, in identifying subgroups that need more intensive follow-up, and in developing interventions to facilitate adjustment to genetic test results.

Correlates of psychologic distress in colorectal cancer patients undergoing genetic testing for hereditary colon cancer

In this article the authors describe the demographic and psychosocial correlates of 2 measures of psychologic distress among 200 colorectal cancer patients undergoing genetic testing for hereditary nonpolyposis colon cancer. The prevalence of symptoms of depression on the Center for Epidemiologic Studies Depression (CES-D) Scale was 24%. In multivariate analysis, female sex, less formal education, fewer sources of social contacts, and less satisfaction with them were associated with high scores on the CES-D Scale. Characteristics associated with high scores on the State-Trait Anxiety Inventory were younger age, less formal education, non-White race, local-regional stage of disease, fewer social contacts, and less satisfaction with them. Information on psychosocial correlates of psychologic distress may prove useful in guiding genetic counseling sessions, in identifying subgroups that need more intensive follow-up, and in developing interventions to facilitate adjustment to genetic test results.