Decreased exposure to sunitinib due to concomitant administration of ifosfamide: results of a phase I and pharmacokinetic study on the combination of sunitinib and ifosfamide in patients with advanced solid malignancies.

BACKGROUND: This study aimed to define the maximally tolerated dose (MTD) of sunitinib combined with two different infusion schedules of ifosfamide. METHODS: Patients with advanced solid tumours, good performance score, good organ function, and no standard therapy available were eligible. Continuous once daily sunitinib, in escalating doses per cohort, was combined with ifosfamide, 9 g m(-2) for 3 days or 6 g m(-2) for 5 days, administered every 3 weeks. Pharmacokinetic (PK) and pharmacodynamic (PD) assessments were performed. RESULTS: With growth-factor support, the MTD of sunitinib combined with either ifosfamide schedule was 12.5 mg in 32 patients enrolled. Neutropenia-related adverse events were dose-limiting toxicities. Sunitinib did not affect ifosfamide PK. Ifosfamide significantly decreased exposure to sunitinib and increased exposure to its metabolite, SU12662. No consistent changes in PD parameters were observed. CONCLUSION: With growth-factor support, the MTD of sunitinib with both ifosfamide schedules was 12.5 mg. Ifosfamide produced decreased sunitinib blood levels because of CYP3A induction. As PK interactions cannot explain the relatively low sunitinib doses that can be combined with ifosfamide, synergy in toxicity is likely. Whether this also holds true for anti-tumour activity needs to be further explored.

Threshold value of subepicardial adipose tissue to detect insulin resistance in obese children.

AIM: Until now, the association between subepicardial adipose tissue (SAT), insulin resistance and intima-media thickness (IMT) has not been evaluated in obese children. In this study, we evaluated whether echocardiographic SAT is related to insulin resistance and IMT in obese children. SUBJECTS AND METHODS: A total of 46 obese subjects (10.2+/-2.5 years of age, 25 male patients) and 30 age- and gender-matched lean subjects (10.8+/-3.1 years of age, 13 male patients) were included in this study. The criterion for diagnosing obesity was defined as the body mass index (BMI) being over 97% percentile of the same gender and age. Serum triglyceride (TG), low- and high-density lipoprotein, cholesterol, glucose and insulin levels were measured during the fasting state. Each subject underwent a transthoracic echocardiogram and the SAT thickness was measured during end-diastole from the parasternal long-axis views. RESULTS: The obese subjects had significantly higher SAT thickness and IMT values compared with the subjects in the control group (5.7+/-1.4 vs 3.0+/-0.7 mm, 0.78+/-0.15 vs 0.51+/-0.11 mm, P=0.001, respectively). Simple linear regression analysis showed no significant correlation between SAT and insulin resistance (r=0.170, P=0.253), whereas there was significant correlation between SAT and BMI, age and IMT (r=0.625, P=0.02, r=0.589, P=0.001, r=0.343, P=0.02, respectively). As an optimal cutoff point, a SAT thickness of 4.1 mm determined insulin resistance with 90% sensitivity and 61% specificity. CONCLUSIONS: Our study showed that SAT was significantly correlated with age, BMI and IMT, but not insulin resistance. However, our findings suggest that a 4.1 mm cutoff of SAT thickness might be used as a simple, inexpensive and non-invasive screening method because of its ability to predict insulin resistance with high sensitivity in obese children.

Pancreatic cancer after remote peptic ulcer surgery.

BACKGROUND: Peptic ulcer surgery may carry an increased risk for pancreatic cancer development. Molecular analysis of K-ras codon 12, frequently mutated in conventional pancreatic cancers, might provide insight into the aetiological mechanisms. METHODS: The relative risk of pancreatic cancer was computed by multivariate and person-year analysis in a cohort of 2633 patients who had undergone gastrectomy. Lung cancer risk was analysed as an indirect means of assessing smoking behaviour. K-ras codon 12 mutational analysis was performed on 15 postgastrectomy pancreatic cancers. RESULTS: There was an overall increased risk of pancreatic carcinoma of 1.8 (95% confidence interval, 1.3 to 2.6) five to 59 years postoperatively, which gradually increased to 3.6 at 35 years or more after surgery (chi(2) test for trend, p < 0.05). Multivariate analysis indicated that parameters other than postoperative interval did not influence the risk. Lung cancer risk was significantly increased after surgery, but no time trend was observed. The spectrum and prevalence of K-ras codon 12 mutations were comparable to conventional pancreatic cancer. CONCLUSIONS: Remote partial gastrectomy is associated with an increased risk of pancreatic cancer. Postgastrectomy and non-postgastrectomy pancreatic cancers may share similar aetiological factors, such as smoking. However, the neoplastic process in patients who have undergone gastrectomy appears to be accelerated by factors related to the surgery itself.

The SMAD4 protein and prognosis of pancreatic ductal adenocarcinoma.

PURPOSE: SMAD4 (also called Dpc4) is a tumor suppressor in the TGF-beta signaling pathway that is genetically inactivated in approximately 55% of all pancreatic adenocarcinomas. We investigated whether prognosis after surgical resection for invasive pancreatic adenocarcinoma is influenced by SMAD4 status. EXPERIMENTAL DESIGN: Using immunohistochemistry, we characterized the SMAD4 protein status of 249 pancreatic adenocarcinomas resected from patients who underwent pancreaticoduodenectomy (Whipple resection) at The Johns Hopkins Hospital, Baltimore, MD, between 1990 and 1997. The SMAD4 gene status of 56 of 249 (22%) pancreatic carcinomas was also determined. A multivariate Cox proportional hazards model assessed the relative risk of mortality associated with SMAD4 status, adjusting for known prognostic variables. RESULTS: Patients with pancreatic adenocarcinomas with SMAD4 protein expression had significantly longer survival (unadjusted median survival was 19.2 months as compared with 14.7 months in patients with pancreatic cancers lacking SMAD4 protein expression; P = 0.03). This SMAD4 survival benefit persisted after adjustment for prognostic factors including tumor size, margins, lymph node status, pathological stage, blood loss, and use of adjuvant chemoradiotherapy. The relative hazard of mortality for cancers lacking SMAD4 after adjusting for other prognostic factors was 1.36 (95% confidence interval, 1.01-1.83; P = 0.04). CONCLUSION: Patients undergoing Whipple resection for pancreatic adenocarcinoma survive longer if their cancers express SMAD4.

Micrometastases in bone marrow of patients with suspected pancreatic and ampullary cancer.

AIMS: This prospective study aimed to evaluate the detection of micrometastases in bone marrow of patients with suspected pancreatic and ampullary cancer and to determine their predictive value on overall survival. METHODS: Between December 1997 and December 1998, 35 patients (19 male, 42-77 years) with suspected pancreatic and ampullary cancer underwent diagnostic laparoscopy as a final staging procedure before exploration. Bone marrow was aspirated from the iliac crest at the beginning of laparoscopy. Mononuclear cells were isolated and stained using the specific monoclonal antibody CAM 5.2. RESULTS: Cytokeratin-positive cells were detected in 12/35 (34%) of all patients. In the 31 patients with a final diagnosis of carcinoma, a positive staining was found in 10/31 (32%) of the bone marrow aspirates. After a median follow-up of 17 months (2-24), 15/31 (48%) patients had died: 7/10 (70%) with and 8/21 (38%) without micrometastases (* P<0.04). All four patients who turned out to have chronic pancreatitis were alive without malignancy. In two of these four patients, distinct cytokeratin-positive cells were seen. CONCLUSIONS: Micrometastases in bone marrow of patients with the final diagnosis pancreatic or ampullary carcinoma seem to predict a significantly shorter survival. However, clinical use of cytokeratin markers cannot be recommended at present, because false-positive staining was found.

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.

Small cell carcinoma of the gallbladder: a clinicopathologic, immunohistochemical, and molecular pathology study of 12 cases.

Small cell carcinomas of the gallbladder are unusual neoplasms that have been characterized only recently. The authors describe the clinical, histopathologic, immunohistochemical, and molecular features of 12 small cell carcinomas of the gallbladder. The mean age at diagnosis was 69 years, and the male-to-female ratio was 5:7. The neoplasms had an average size of 3 cm, and 90% showed invasion of the muscularis propria and perimuscular connective tissue. Seventy-five percent of the carcinomas had metastasized or extended locally beyond the gallbladder at surgery. Survival was uniformly poor, with a mean survival of 10.7 months (range, 3-25 months). Half the small cell carcinomas were combined with other neoplasms. Four had foci of adenocarcinoma, one contained areas of squamous differentiation, and another had a component of carcinosarcoma. Immunohistochemical analysis showed focal reactivity for chromogranin (six of six cases), neuron-specific enolase (six of six cases), and Leu-7 (three of three cases). The molecular changes in small cell carcinomas were similar to those of adenocarcinomas occurring at this site, with a high frequency of p53 (75%) and p16INK4a (33%) abnormalities, and a low frequency of deleted in pancreatic carcinoma-4 inactivation (0%) and K-ras codon 12 mutations (17%). In contrast to pulmonary small cell carcinomas, p16INK4a function appears to be abrogated more frequently in these carcinomas.

Immunohistochemical labeling for the Dpc4 gene product is a specific marker for adenocarcinoma in biopsy specimens of the pancreas and bile duct.

We immunohistochemically labeled 72 biopsy specimens from the extrahepatic biliary tree and pancreas for Dpc4 protein and correlated expression with histologic diagnosis and patient follow-up. Specimens were classified histologically as follows: nonneoplastic, 35; neoplastic, 22; atypical, 15. Loss of expression of Dpc4 protein was identified in 12 specimens; 11 were histologically diagnostic of carcinoma. The 12th specimen was from a patient whose biopsy specimen initially was diagnosed as "atypical," but clinical follow-up revealed adenocarcinoma. Of the 12 atypical biopsy specimens with intact expression for Dpc4, follow-up later revealed that 10 were adenocarcinoma. Loss of expression of Dpc4 protein was never identified in a benign specimen. Immunohistochemical labeling for the Dpc4 gene product is a specific marker of carcinoma in biopsy specimens of the pancreas and extrahepatic bile ducts and is marginally helpful in classifying atypical specimens. The sensitivity for carcinoma is low. This latter finding is not unexpected, because the DPC4 tumor suppressor gene is inactivated in only about half of pancreatic and biliary malignant neoplasms. Importantly, loss of Dpc4 expression has been reported in in situ carcinomas, suggesting that loss of expression should not be equated with invasive carcinoma.

Carcinoid tumors of the extrahepatic bile ducts: a study of seven cases.

The authors report seven patients with carcinoid tumors of the extrahepatic bile ducts (EHBDs). All patients were women, with an average age at diagnosis of 49.8 years (range, 37-67 yrs). The most common presenting symptom was painless jaundice with or without pruritus. Although one patient had peptic ulcer disease before the onset of obstructive jaundice, none had systemic endocrine manifestations. These neoplasms were most often located in the common bile duct. Grossly, the carcinoid tumors were usually nodular and poorly demarcated, and ranged from 1.1 to 2.7 cm in size. Only one of the neoplasms was polypoid. Microscopically, the tumors had a trabecular or nesting pattern with occasional tubule formation, and were composed of relatively small cells with granular chromatin. All of the neoplasms expressed chromogranin and two expressed synaptophysin. Three expressed serotonin and two of the three were also immunoreactive for pancreatic polypeptide or somatostatin. Two tumors were focally positive for gastrin and one of these two tumors was also positive for serotonin and pancreatic polypeptide. All seven carcinoid tumors showed no immunoreactivity for p53, and assays for p53 loss of heterozygosity analysis were negative in two, suggesting that p53 mutations do not play a role in the pathogenesis of EHBD carcinoids. A mutation in codon 12 of K-ras was found in one carcinoid tumor whereas two of two showed immunoreactivity for Dpc4 protein. In view of the small number of carcinoids studied, the importance of these findings in the pathogenesis of these tumors is unclear. Ultrastructural examination of three of the tumors revealed numerous membrane-bound, round neurosecretory granules. Clinically, these lesions had an indolent course. Even in the presence of lymph node metastases (noted in two patients), all of the patients remained disease free 2 to 11 years (average follow up, 6.6 yrs) after segmental resection or pancreaticoduodenectomy (Whipple's procedure). Because carcinoid tumors of the EHBD are of low malignant potential, they should be separated from the more common adenocarcinomas in this location.

Genetic, immunohistochemical, and clinical features of medullary carcinoma of the pancreas: A newly described and characterized entity.

Medullary carcinomas of the pancreas are a recently described, histologically distinct subset of poorly differentiated adenocarcinomas that may have a unique pathogenesis and clinical course. To further evaluate these neoplasms, we studied genetic, pathological, and clinical features of 13 newly identified medullary carcinomas of the pancreas. Nine (69%) of these had wild-type K-ras genes, and one had microsatellite instability (MSI). This MSI medullary carcinoma, along with three previously reported MSI medullary carcinomas, were examined immunohistochemically for Mlh1 and Msh2 expression, and all four expressed Msh2 but did not express Mlh1. In contrast, all of the medullary carcinomas without MSI expressed both Msh2 and Mlh1. Remarkably, the MSI medullary carcinoma of the pancreas in the present series arose in a patient with a synchronous but histologically distinct cecal carcinoma that also had MSI and did not express Mlh1. The synchronous occurrence of two MSI carcinomas suggests an inherited basis for the development of these carcinomas. Indeed, the medullary phenotype, irrespective of MSI, was highly associated with a family history of cancer in first-degree relatives (P < 0.001). Finally, one medullary carcinoma with lymphoepithelioma-like features contained Epstein-Barr virus-encoded RNA-1 by in situ hybridization. Therefore, because of medullary carcinoma's special genetic, immunohistochemical, and clinical features, recognition of the medullary variant of pancreatic adenocarcinoma is important. Only by classifying medullary carcinoma as special subset of adenocarcinoma can we hope to further elucidate its unique pathogenesis.

Pancreatic mucinous cystic neoplasms with sarcomatous stroma: molecular evidence for monoclonal origin with subsequent divergence of the epithelial and sarcomatous components.

Neoplasms with mixed carcinomatous and sarcomatous growth patterns occur in many organs and tissues. The pathogenesis of these cancers is thought to be either the result of two independent neoplastic processes merging to form a single tumor, or a neoplasm of monoclonal origin that develops phenotypic diversity. To address this issue, we characterized molecular alterations in separately microdissected epithelial and sarcomatous areas in three cases of pancreatic mucinous cystic neoplasms with sarcomatous stroma. Using microsatellite markers for six chromosomal loci commonly deleted in infiltrating ductal adenocarcinomas of the pancreas, we found genetic alterations to be virtually identical between the sarcomatous and epithelial components of two of the three neoplasms. In the third neoplasm, we found allelic losses and retentions to be identical at five of the six chromosomal loci, but at a single locus, we noted allelic loss in the neoplastic epithelial component but not the sarcomatous component. The same neoplasms were also analyzed for activating point mutations in codon 12 of the K-ras gene by using mutant-enriched polymerase chain reaction and allele-specific oligonucleotide hybridization. A K-ras mutation was identified in the epithelial component of one of the three neoplasms (the same tumor with an additional allelic loss in the neoplastic epithelial cells), but the sarcomatous component of this tumor was wild-type at codon 12 of K-ras, as were both components of the other two neoplasms. Overall, these results suggest a monoclonal origin with subsequent divergence of the neoplastic epithelial and sarcomatous portions of these neoplasms.

Diagnostic p53 immunostaining of endobiliary brush cytology: preoperative cytology compared with the surgical specimen.

BACKGROUND: Endobiliary brush cytology is important in the distinction of malignant and benign causes of extrahepatic bile duct obstruction. The additional diagnostic value of p53 immunostaining on these cytology specimens was assessed. METHODS: All patients with extrahepatic bile duct obstruction who underwent endoscopic retrograde cholangiopancreatography (ERCP) with endobiliary brush cytology and subsequent surgery at the Academic Medical Center in Amsterdam during a 3-year period were studied. p53 Immunocytology was compared with the corresponding conventional light microscopic cytology and p53 immunostaining of the subsequent surgical specimen. RESULTS: Fifty-three patients with the following diagnoses were included: pancreatic carcinoma (23), bile duct carcinoma (15), ampullary carcinoma (5), lymph node metastases (2), carcinoma of unknown origin (4), chronic pancreatitis (3), and primary sclerosing cholangitis (1). Fifty-one percent of the carcinomas showed positive p53 immunostaining; all four surgical specimens without carcinoma were negative. The sensitivities of conventional light microscopic cytology, p53 immunocytology, and both tests combined were 29%, 24%, and 43%, respectively. These sensitivities were higher in cases of bile duct carcinoma (46%, 40%, and 66%) compared with cases of pancreatic carcinoma (13%, 9%, and 22%). Specificities of both tests were 100%. CONCLUSIONS: p53 Immunostaining on endobiliary brush cytology may be helpful in the diagnosis of malignant extrahepatic bile duct stenosis, especially in patients with bile duct carcinoma. Cancer (Cancer Cytopathol)

Role of tumor markers and mutations in cells and pancreatic juice in the diagnosis of pancreatic cancer.

BACKGROUND: Unresectability at the time of presentation is the most important reason for the poor survival rate of pancreatic carcinoma. Molecular-based tests might improve the early detection of pancreatic cancer at a time when surgical resection is still an option for cure. METHODS: The literature was reviewed concerning the role of molecular-based tests applied to sources other than pancreatic tissue itself, including ERCP-samples, blood and stool, with emphasis on the detection of K-ras mutations and mutant p53 gene product. RESULTS: K-ras mutations have been successfully detected in ERCP brush samples, leading to an increase of the sensitivity and improvement of the diagnostic yield. When pancreatic juice and duodenal fluid are tested for K-ras mutations, the yield is less. K-ras mutations can also be detected in the blood, especially in patients with larger tumors. The presence of K-ras mutations proved also to be useful in discriminating benign and malignant liver nodules, i.e. when during surgery there is suspicion of liver metastases of pancreatic cancer. The accumulation of p53 gene product to immunochemically detectable levels in ERCP brush samples also increases the sensitivity of conventional light microscopy. Other molecular markers such as telomerase and TIMP-1 may prove to be useful too, but await more extensive evaluation. CONCLUSION: Molecular-based tests may be of value in the early detection of pancreatic cancer and might therefore contribute to a better patient survival rate.

Remote partial gastrectomy as a risk factor for pancreatic cancer: potential for preventive strategies.

BACKGROUND: Pancreatic cancer is the fifth leading cause of cancer death mainly because of an advanced disease stage at the time of diagnosis. Patients with a remote partial gastrectomy for benign ulcer disease may constitute a high risk group for pancreatic cancer; an increased index of suspicion could potentially lead to early detection in these patients. METHODS: The risk of developing pancreatic cancer following partial gastrectomy was evaluated by reviewing the literature. Furthermore, the risk of pancreatic cancer in an Amsterdam cohort of 2633 postgastrectomy patients has recently been assessed. The presence and type of K-ras codon 12 mutations in 15 postgastrectomy pancreatic cancer cases were also determined and compared to the conventional spectrum of these mutations in sporadic pancreatic cancer. RESULTS: After a follow-up time of 20 years or more since peptic ulcer surgery, the relative risk reported in the literature varies from 1.65 to 5-fold. In the Amsterdam cohort of 2633 postgastrectomy patients an overall increased risk of 1.8 was observed. The risk gradually increases to 3.6 after a postoperative interval of 35 years or more. A comparable frequency and type of K-ras codon 12 mutations was found in the postgastrectomy pancreatic cancer cases as reported in sporadic pancreatic cancer in non-operated patients, suggesting a similar carcinogenesis in the two groups and indicating a potential utility of this molecular marker for surveillance strategies. CONCLUSIONS: Patients who underwent peptic ulcer surgery are at higher risk of developing subsequent pancreatic cancer, especially after a prolonged (> 20 yrs) postoperative interval. An increased index of suspicion may contribute to early detection in these patients. The similar K-ras codon 12 mutation pattern in conventional and postgastrectomy pancreatic cancers makes this a suitable target for molecular diagnosis in these patients.

Value of brush cytology for dominant strictures in primary sclerosing cholangitis.

BACKGROUND AND STUDY AIMS: Around 10% of patients with primary sclerosing cholangitis (PSC) develop cholangiocarcinoma, which is cholangiographically often indistinguishable from a benign dominant stricture. The aim of the present study was to assess the value of brush cytology in discriminating between benign and malignant dominant strictures in primary sclerosing cholangitis. PATIENTS AND METHODS: The results of all brush cytology specimens from dominant strictures from patients with established primary sclerosing cholangitis, taken at endoscopic retrograde cholangiopancreatography between 1987 and 1996, were compared with the histological diagnosis or clinical status of the patients at least 2 years later. RESULTS: A total of 47 brush cytology samples, taken between 1987 and 1996, from 43 PSC patients could be included. Between 1993 and 1996, p53 immunocytochemical examination was done in 27 brush cytology specimens and K-ras mutation analysis in 25 patients. The sensitivity, specificity, positive predictive value, and negative predictive value of brush cytology for detection of malignancy were 60%, 89%, 59%, and 89%, respectively. These figures were not improved by adding the results of p53 and K-ras analysis. Logistic regression analysis did not reveal any additional benefit of p53 or K-ras analysis either. Prior stenting did not adversely affect specificity. CONCLUSIONS: The sensitivity and positive predictive value of brush cytology for dominant strictures in PSC are rather poor. The specificity and negative predictive value are reasonably good. There was no additional value from p53 immunocytochemistry and K-ras mutation analysis. Prior stenting did not affect the results.

Neurofibromatosis type 2 protein co-localizes with elements of the cytoskeleton.

The product of the neurofibromatosis type 2 (NF2) tumor suppressor gene is a 595-amino-acid protein bearing resemblance to a family of band-4.1-related proteins. These proteins, including ezrin, radixin, and moesin, probably function as molecular linking proteins, connecting the cytoskeleton to the cell membrane. On the grounds of the homology to the ezrin, radixin, and moesin proteins and on the basis of its predicted secondary structure, the NF2 protein is also thought to act as a cytoskeleton-cell membrane linking protein. Using monoclonal antibodies to amino- and carboxyl-terminal synthetic NF2 peptides we demonstrate the co-localization of the NF2 protein with elements of the cytoskeleton in a COS cell model system and in cultured human cells. Furthermore, the presence of the NF2 protein in tissue sections is shown. The monoclonal antibodies specifically stain smooth muscle cells and the stratum granulosum of the human epidermis. In cultured smooth muscle cells the NF2 protein co-localizes with actin stress fibers. Immunoelectron microscopy demonstrates the presence of the NF2 protein associated with keratohyalin granules and to a lesser extent with intermediate filaments in the human epidermis. We conclude that the NF2 protein is indeed associated with multiple elements of the cytoskeleton.