Nationwide comprehensive gastro-intestinal cancer cohorts: the 3P initiative

BACKGROUND

The increasing sub-classification of cancer patients due to more detailed molecular classification of tumors, and limitations of current trial designs, require innovative research designs. We present the design, governance and current standing of three comprehensive nationwide cohorts including pancreatic, esophageal/gastric, and colorectal cancer patients (NCT02070146). Multidisciplinary collection of clinical data, tumor tissue, blood samples, and patient-reported outcome (PRO) measures with a nationwide coverage, provides the infrastructure for future and novel trial designs and facilitates research to improve outcomes of gastrointestinal cancer patients.

MATERIAL AND METHODS

All patients aged ≥18 years with pancreatic, esophageal/gastric or colorectal cancer are eligible. Patients provide informed consent for: (1) reuse of clinical data; (2) biobanking of primary tumor tissue; (3) collection of blood samples; (4) to be informed about relevant newly identified genomic aberrations; (5) collection of longitudinal PROs; and (6) to receive information on new interventional studies and possible participation in cohort multiple randomized controlled trials (cmRCT) in the future.

RESULTS

In 2015, clinical data of 21,758 newly diagnosed patients were collected in the Netherlands Cancer Registry. Additional clinical data on the surgical procedures were registered in surgical audits for 13,845 patients. Within the first two years, tumor tissue and blood samples were obtained from 1507 patients; during this period, 1180 patients were included in the PRO registry. Response rate for PROs was 90%. The consent rate to receive information on new interventional studies and possible participation in cmRCTs in the future was >85%. The number of hospitals participating in the cohorts is steadily increasing.

CONCLUSION

A comprehensive nationwide multidisciplinary gastrointestinal cancer cohort is feasible and surpasses the limitations of classical study designs. With this initiative, novel and innovative studies can be performed in an efficient, safe, and comprehensive setting.

[A giant pseudocyst following repair of an incisional hernia by a propylene mesh]

A 79-year-old woman presented with a huge, asymptomatic, balloon-like abdomen, which gradually developed after polypropylene mesh repair of an incisional hernia following a median laparotomy. Additional CT showed a huge cyst measuring 20 x 24 cm which seemed to originate from the anterior abdominal wall and lacked communication with the inner abdominal space. Subsequently an explorative laparotomy was performed. The content of the cyst consisted of dark brown serosanguineous material. The inferior portion was firmly affixed to the mesh. The entire cyst, except for the part fixed to the mesh, was excised followed by an abdominoplasty. Histological examination showed aspecific signs of inflammation due to a foreign body, and haemorrhagic material without epithelial lining. The diagnosis 'giant pseudocyst' was established. Etiologically, this condition is probably related to postoperative formation of a seroma, which is a well-known complication after mesh repair, especially when a polypropylene mesh is used. Postoperative formation of a haematoma might be a causative factor as well. Former literature reports 11 cases of such giant cyst formation after mesh repair ofhernias. In one study a prevalence of 0.45% is mentioned. This complication may be an underreported phenomenon.

Endoscopic management of common bile duct stones leaving the gallbladder in situ. A cohort study with long-term follow-up

BACKGROUND

Obstructive jaundice caused by stones is a common disorder, mostly managed by endoscopic sphincterotomy followed by cholecystectomy. The aim of this study was to evaluate whether or not clearance of the common bile duct alone is sufficient as treatment for patients with choledocholithiasis.

METHODS

A cohort with 447 patients with symptomatic cholecystocholedocholithiasis, undergoing endoscopic retrograde cholangiography (ERC) and if necessary sphincterotomy (ES). In 164 patients common bile duct stones were proven and treated endoscopically, without performing a subsequent cholecystectomy. All 164 patients were free of symptoms after the endoscopic intervention. This group of patients was compared with 78 patients who underwent cholecystectomy after endoscopic treatment of common bile duct stones. Patients were followed for 1-13 years after ERC and sphincterotomy results and complications were registered.

RESULTS

The ages of the 164 patients in the in situ group were significantly higher than in the cholecystectomy group and the ASA classification (American Society of Anesthesiologists) was significantly higher in the in situ patients. Mean follow-up was 70.9 months. Of the in situ patients 27 (16%) returned with biliary symptoms; 12 with common bile duct stones, three with cholangitis, and one with stenosis of Vater's papilla. Eight patients returned with cholecystitis and 3 with symptomatic cholecystolithiasis. Thirteen patients underwent cholecystectomy and 11 were managed (also) endoscopically. Minor complications were 2 wound infections and 1 bleeding after cholecystectomy. Two patients (1%) died of abdominal sepsis due to cholecystitis. Of the patients who underwent cholecystectomy, 6 (7.6%) returned during follow-up. Three patients had common bile duct stones, 2 had cholangitis and 1 patient presented with papillostenosis. Three patients needed surgical common bile duct exploration and the other 3 were treated endoscopically. After reintervention, cardiopulmonary complications were observed in 1 patient. There was no related death.

CONCLUSION

When common bile duct stones are treated successfully by endoscopic sphincterotomy and patients are free of symptoms, there is no need for routine prophylactic cholecystectomy.

GSTP1 CpG island hypermethylation is responsible for the absence of GSTP1 expression in human prostate cancer cells

GSTP1 CpG island hypermethylation is the most common somatic genome alteration described for human prostate cancer (PCA); lack of GSTP1 expression is characteristic of human PCA cells in vivo. We report here that loss of GSTP1 function may have been selected during the pathogenesis of human PCA. Using a variety of techniques to detect GSTP1 CpG island DNA hypermethylation in PCA DNA, we found only hypermethylated GSTP1 alleles in each PCA cell in all but two PCA cases studied. In these two cases, CpG island hypermethylation was present at only one of two GSTP1 alleles in PCA DNA. In one of the cases, DNA hypermethylation at one GSTP1 allele and deletion of the other GSTP1 allele were evident. In the other case, an unmethylated GSTP1 allele was detected, accompanied by abundant GSTP1 expression. GSTP1 CpG island DNA hypermethylation was responsible for lack of GSTP1 expression by LNCaP PCA cells: treatment of the cells with 5-azacytidine (5-aza-C), an inhibitor of DNA methyltransferases, reversed the GSTP1 promoter DNA hypermethylation, activated GSTP1 transcription, and restored GSTP1 expression. GSTP1 promoter activity, assessed via transfection of GSTP1 promoter-CAT reporter constructs in LNCaP cells, was inhibited by SssI-catalyzed CpG dinucleotide methylation. Remarkably, although selection for loss of GSTP1 function may be inferred for human PCA, GSTP1 did not act like a tumor suppressor gene, as LNCaP cells expressing GSTP1, either after 5-aza-C treatment or as a consequence of transfection with GSTP1 cDNA, grew well in vitro and in vivo. Perhaps, GSTP1 inactivation may render prostatic cells susceptible to additional genome alterations, caused by electrophilic or oxidant carcinogens, that provide a selective growth advantage.

[Luxatio cordis in blunt-trauma thoraco-abdominal injuries]

A 56-year old woman was admitted to the emergency ward after suffering a blunt thoraco-abdominal high-velocity trauma as she hit the wheel when her car drove into a tree. A laparotomy was performed because of haemodynamic instability and radiographic suspicion of a diaphragmatic rupture. Besides haemorrhage from liver and spleen injuries, an abdominal herniation of the heart through a ruptured pericardium and diaphragm was found. Haemostasis of liver, splenectomy and suturing of defects in pericardium and diaphragm resulted in a haemodynamically stable situation. A high index of suspicion of rupture of pericardium and diaphragm with luxation of the heart in the trauma patient is important to reduce morbidity and mortality due to delay of surgical intervention.