p16 and K-ras gene mutations in the intraductal precursors of human pancreatic adenocarcinoma

Pancreatic adenocarcinoma is thought to arise from a noninvasive neoplastic precursor, the pancreatic intraductal lesion (PIL). Mutations of the K-ras gene are known to occur in PILs, but their high prevalence among PILs within the general population probably limit the use of K-ras as a marker of eventual clinical risk. In search of genetic constellations that might indicate the progression of some PILs toward an invasive phenotype, mutations at both the K-ras and p16 genes were sought within PILs of 10 pancreata resected for adenocarcinoma. K-ras mutations were present in most PILs and in nearly all PILs having nuclear atypia. In half of the patients, two or more unique K-ras mutations were identified among distinct PILs, which is evidence for the separate clonal evolution of multiple pancreatic neoplasms within individual patients. p16 alterations (one homozygous deletion and three point mutations) were found in 4 of the 10 carcinomas; these four pancreata harbored p16 alterations in three of nine PILs, of which one was a "histologically early" lesion. Two patients had p16 alterations in PILs matching those of the associated carcinomas. p16 mutations were not found in PILs of pancreata having wild-type p16 in the carcinoma, nor were they found in ducts having normal histology. It is suggested that alterations of the p16 gene affect a subset of PILs that contain mutations of the K-ras gene and that these mutations might identify high-risk precursors of the invasive malignancy.     

Initiating genetic events in small renal neoplasms detected by comparative genomic hybridization

PURPOSE: To identify the genetic alterations associated with renal adenomas. MATERIALS AND METHODS: We analyzed 37 renal adenomas obtained at autopsy (23 papillary and 14 non-papillary) by comparative genomic hybridization. RESULTS: In papillary tumors, the median number of gains and losses of genetic material per tumor was 2.0 and 1.0, respectively. Papillary tumors were characterized predominantly by gains of genetic material on chromosomes 7 (57%), 17 (35%), 16 (26%), 12 (26%), 3 (22%), 20 (22%) and loss of a sex chromosome (83%). In 6 papillary tumors less than or equal to 5 mm. in diameter, gain of chromosome 7 occurred in 4 specimens. Initiating events for papillary renal adenomas include gain of chromosome 7 and loss of a sex chromosome. In non-papillary tumors, the median number of gains and losses of genetic material per tumor was 1.0 and 1.0, respectively. Non-papillary tumors were characterized by loss of genetic material on chromosome 3p (50%), loss of a sex chromosome (36%) and a gain of chromosome 5 (43%). The initiating event for non-papillary renal adenomas is the loss of chromosome 3p. CONCLUSIONS: Renal adenomas demonstrate similar genetic alterations as clinically detected renal cell carcinomas. Their clinically indolent course may, in part, be a result of the lower number of genetic alterations per tumor than their clinically detected counterparts. Renal adenomas are thus small carcinomas which have not yet acquired the necessary genetic alterations leading to tumor progression.     

Prevalence and clinical significance of combined K-ras mutation and p53 aberration in pancreatic adenocarcinoma

CONCLUSION: This study could not attribute survival differences to the coincident acquisition of two common genetic alterations, K-ras mutation and p53 overexpression in pancreatic adenocarcinoma patients. Additionally, our data indicate the converse to be true: Those patients lacking both K-ras mutation and aberrant p53 expression showed the shortest survival when compared with cases showing either alteration or both. This study also showed the negative effect of K-ras mutation and p53 expression on pancreas cancer patients' survival after treatment with either radiation therapy or chemotherapy. BACKGROUND: Mutations of the oncogene K-ras at codon 12 are reported to be the most common genetic alteration in pancreatic carcinoma, whereas either overexpression or mutation of the tumor suppressor p53 gene is considered the most common genetic alteration in neoplasia of all types. p53 overexpression has been attributed to survival differences in pancreatic carcinoma, but such association is still controversial. No studies have fully documented the combined incidence of K-ras and p53 alterations in pancreatic adenocarcinoma, or their combined effect on patient survival in a large case series. The influence of radiation or chemotherapy in groups showing both, either, or neither mutation is also undocumented. METHODS: Paraffin-embedded tissue sections from 76 cases of pancreatic adenocarcinoma were cut for DNA extraction for K-ras analysis and immunohistochemical staining for aberrant p53 expression. K-ras mutation was determined by single-strand conformation polymorphism (SSCP) and slot-blot allele-specific oligonucleotide (ASO) hybridization of PCR-amplified DNA product p53 expression was scored on the basis of percent nuclear staining with the MAb DO7. RESULTS: Sixty-four of 76 cases (84%) showed K-ras mutation, p53 expression, or both, K-ras was mutated in 55 of 76 cases (72%). p53 was expressed in 33 of 76 cases (43%). Twenty-four of 76 cases (31%) showed both K-ras mutation and p53 expression. The presence of both alterations was not related to significant differences in tumor grade, stage, or survival compared to either alteration alone. A sizable subset (16% of cases) lacked either alteration, and surprisingly, this group showed the shortest median survival compared to those with K-ras mutation, p53 expression, or both (p = 0.024). Patients whose tumors were K-ras-negative showed the greatest difference in median survival with radiation therapy (median survival 30.8 mo vs 7.8 mo with no radiation, p = 0.005).     

Demonstration of microcystic disease of the pancreas by magnetic resonance cholangiopancreatography: report of a case

A case of microcystic disease of the pancreas which was clearly demonstrated by magnetic resonance cholangiopancreatography (MRCP) is reported herein. Cystic dilatation of the pancreatic duct was recognized by computed tomography scanning and endoscopic retrograde cholangiopancreatography (ERCP). Furthermore, the existence of microcystic clusters surrounding the dilated pancreatic duct were clearly visualized by MRCP. These microcystic clusters were strongly suspected preoperatively of having caused dilatation of the major pancreatic duct. Based on these findings, a distal pancreatectomy was performed. The operative specimen showed no accumulation of mucin and no evident lesions in the dilated pancreatic duct, being inconsistent with the entity of a mucus-producing tumor. Pathological examination revealed that the inner parts of microcysts constituted columnar epithelium with mucus production and papillary growth. Thus, a final histological diagnosis of intraductal papillary adenoma with idiopathic pancreatic duct ectasia was confirmed. In conclusion, MRCP, being a less aggressive diagnostic procedure than ERCP, proved extremely useful for obtaining precise information on cystic lesions of the pancreas in this patient.     

Ultrasound guided percutaneous fine needle aspiration cytology of pancreas: a review of 61 cases

The study includes 61 cases which were subjected to ultrasound (US) guided fine needle aspiration cytology (FNAC) to find out the utility of this technique in the diagnosis of pancreatic lesions. Age of the patients ranged from 23 to 85 years with a median of 50 years. Male to female ratio was 36:25. One or more clinical diagnoses were offered in 16 and in 9 of these, the disease was related to pancreas. Subsequent to US, the lesions were localized to pancreas in 57 and the nature of pathology in the pancreatic lesion could be diagnosed in 31. By FNAC, 31 cases (50.8%) were diagnosed to have pancreatic malignancy which included adenocarcinoma (23 cases), papillary cystic tumour (1), muco-epidermoid carcinoma (1), acinic cell carcinoma (1), islet cell tumor (1), and non Hodgkin lymphoma (4). FNAC of liver in 2 cases and retroperitoneal lymph node in a case of pancreatic adenocarcinoma revealed metastasis. During follow up, 1 case of non Hodgkin's lymphoma showed CSF involvement. Three cases (4.9%) were suspected to have epithelial malignancy of which one was confirmed as an adenocarcinoma following surgery and histology. Four (6.6%) were benign lesions which included nonspecific inflammation (2 cases), tuberculous pancreatitis (1) and pseudopancreatic cyst (1). The remaining 23 cases (37.7%) had normal or inadequate cytology. Of these, FNAC of liver showed metastasis in 2 cases and one case each were diagnosed as adenocarcinoma and pseudopancreatic cyst respectively following surgery. None of the patients had any complication following FNAC. We recommend US guided FNAC to be routinely used for diagnosis of pancreatic lesion.     

Prognosis and treatment of bile duct carcinoma

Bile duct carcinomas present a therapeutic challenge because of different histologies, tumor locations, and resectabilities. The goal of our study was to identify prognostic factors to better delineate therapeutic options. Forty patients (30 males and 10 females) diagnosed with bile duct cancer, treated between 1985 and 1996, at Kaiser Permanente Medical Center, Los Angeles were retrospectively reviewed. Three prognostically significant variables were identified: tumor histology, tumor location, and resection. Papillary histology was the most significant determinant of long-term survival. Of six patients with papillary adenocarcinoma, four patients (67%) underwent resection, with all four achieving long-term survival. Lower-third lesions also demonstrated a survival advantage. Four out of 12 (33%) lower-third tumors were resected, with a median survival of 36 months. Irrespective of tumor histology or tumor location, tumor resection always afforded longer survival times than did palliative treatments. A prognostic classification system based on weighted values of significant variables is presented that accurately predicted long-term survival. In conclusion, bile duct tumors in general are incurable, except perhaps for a small subset of patients with papillary adenocarcinoma. Papillary histology is the most significant determinant of ultimate survival and cure. A multifunctional prognostic classification system can be helpful for this perplexing disease.     

Loss of heterozygosity of the von Hippel Lindau gene locus in polypoid dysplasia but not flat dysplasia in ulcerative colitis or sporadic adenomas

Carcinoma in ulcerative colitis (UC) develops from dysplastic precursor lesions, which include flat dysplasia (FD) and polypoid dysplasias (PD). PD may present as single or multiple polypoid structures or as plaque-like lesions that, independent of histological grade, are an indication for colectomy. PDs are histologically similar to adenomas and may not be readily distinguished by light microscopy. It is not known whether FD and PD are different entities, or whether they represent etiologically similar lesions with different morphological expression. We microdissected 25 cases of UC with PD and 19 samples of FD with surrounding chronic colitis (CC) in UC. Loss of heterozygosity (LOH) at the von Hippel Lindau (vHL) gene locus and the putative tumor suppressor genes APC, INK4A (9p16), and p53 was studied. LOH of the vHL gene, INK4A (9p16), and APC was also studied in 11 sporadic adenomas of the colon. LOH at the vHL locus was present in 50% of the samples of PD and in 12% of the samples of FD. LOH was seen in CC close to PD and FD in 26% and 12% of cases, respectively. No adenoma showed LOH of the vHL gene markers studied. LOH in p53 was seen in PD in 16% cases and in FD in 42% cases and in CC close to PD and FD in 0% and 14% cases, respectively. LOH patterns between PD and FD of the markers for APC and 9p16 were not different. LOH in APC was seen in two of five cases of adenoma. We conclude that PD and FD share genetic alterations in APC and 9p16 genes. More frequent involvement of the VHL gene in PD and surrounding CC and involvement of p53 in HGD and CC in FD may represent genetic differences between the development of PD and FD and may be the cause of the different morphology. The infrequency of LOH at the vHL locus in adenomas versus PD may serve as a discriminator between adenomas and PD in diagnostically problematic cases.     

Evaluation of intraductal ultrasonography in the diagnosis of pancreatic cancer

An intraductal ultrasound (IDUS) probe which is inserted via the papilla into the main pancreatic duct (MPD) was evaluated in the diagnosis of 20 patients with pancreatic cancer. The examination was successfully performed with the probe in 17 of the patients (85%). Due to its high frequency (30 MHz) the probe only allowed visualization of the ductal wall and the immediate periductal vicinity (up to about 10 mm). In 15 of the 20 patients the tumors were surgically resected and IDUS scanning was also performed in vitro on the resection specimens, the results being compared to those of histopathological examination. Of these 15 patients, 13 were found to have ductal adenocarcinomas and all but one had been unequivocally diagnosed as having such by ultrasonography (US), computed tomography (CT), endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasonography (EUS). IDUS showed an echorich area (corresponding to cancerous canaliculi on histopathological examination), surrounded by an echopoor area (abundant stroma). This pattern was classified as type I. In two patients with intraductal papillary carcinomas in whom a conclusive diagnosis was not established on US, CT, EUS or ERCP, IDUS showed tumorous tissue with an inhomogeneous echopattern outside (type II) or within (type III) the duct. These results show that IDUS offers valuable diagnostic information complementary to ERCP especially in cases of intraductal papillary tumors. Whether the high resolution imaging of the duct and the paraductal tissue can be used to differentiate between the different forms of pancreatic lesions (inflammation, neoplasms) has to be investigated further.     

Auditory evoked potentials in a patient with a unilateral lesion of the inferior colliculus and medial geniculate body

To reveal any association between the histological type and grade of intraductal breast neoplasms and the manner of accumulation of gene alterations, eight types of gene alterations, i.e., loss of heterozygosity (LOH) on chromosomal arms 16p, 16q, 17p, 17q, and 18q, amplification of the c-erbB-2 and hst-1/int-2 genes, and mutation of the p53 gene, were examined by Southern blot analysis or single-strand conformation polymorphism analysis in a total of 60 cases of intraductal breast cancer and 18 nonmalignant proliferative lesions. Among the histological types and three histological grade groups of intraductal carcinomas, the gene alterations which occurred most frequently were LOH on 16q alone in non-comedo type and Grade 1, alterations of c-erbB-2, 17p, and 16q in comedo type and Grade 2, and alterations of 17q and p53 as well as those of 16q, 17p, and c-erbB-2 in Grade 3. LOH on 16q and 18q was frequent in intraductal carcinoma of the intracystic papillary type, whereas LOH on 18q alone was detected in 27% of papillomas. Among intraductal carcinomas, the mean number of gene alterations was largest in comedo type and Grade 3, whereas it was smallest in non-comedo type and Grade 1. It was possible that LOH on 18q and 16q was involved frequently in papillary tumori-genesis and acquisition of malignant phenotype, respectively, whereas most of the other gene alterations were involved in acquisition of aggressive biological properties by intraductal carcinoma cells. It was also possible that the phenotype of breast neoplasms was determined by the combination of gene alterations at a relatively early developmental stage.     

Sex-lethal, the master sex-determining gene in Drosophila, is not sex-specifically regulated in Musca domestica

BACKGROUND: Previously, the authors reported that 82% of cases of pancreatic carcinoma were positive for p53 in cytologic specimens obtained by selective endoscopic pancreatic duct brushing (SEPB). However, there was an extreme discrepancy between the authors' data of p53 overexpression using cytologic specimens and other reports using surgically resected specimens. In this study, the authors demonstrate that p53 positive cells precisely reflect its gene mutations, and also establish systematic procedures for the preoperative diagnosis of patients with pancreatic carcinoma. METHODS: The authors examined 44 cases of pancreatic carcinoma, 30 cases of chronic pancreatitis, and 9 cases of papillary adenoma. In all cases, pathologic diagnosis was made by surgery or autopsy. The conventional cytology and p53 immunocytology were performed simultaneously in the cell specimens obtained by SEPB. In the cases immunostained for p53, DNA was extracted selectively from p53 immunostained cells using a light microscope. p53 mutations in exons 5 to 8 were examined by direct sequencing. RESULTS: Forty of 44 pancreatic carcinomas (91%) were diagnosed correctly by the methods of conventional cytology associated with p53 immunocytology. p53 mutations were detected in 12 of 14 cases that were positive for p53 (86%). Four of six cases that were inoperable due to massive metastasis or invasion had the mutation at codon 273 (CGT to CAT) in exon 8. CONCLUSIONS: These results suggest that p53 immunocytology reflects its gene mutations precisely, and that the point mutation at codon 273 (CGT to CAT) of p53 may play an important role in the invasive potential and metastasis of pancreatic carcinoma.     

Pathways leading to glioblastoma multiforme: a molecular analysis of genetic alterations in 65 astrocytic tumors

To characterize some of the genetic events underlying the development of glioblastoma multiforme, the authors analyzed 65 astrocytic tumors (seven pilocytic astrocytomas, eight astrocytomas, 16 anaplastic astrocytomas, and 34 glioblastomas multiforme) for loss of heterozygosity for chromosome 17p, loss of heterozygosity for chromosomes 10p and 10q, amplification of the epidermal growth factor receptor (EGFR) gene, and amplification of the oncogenes N-myc, c-myc, and N-ras using Southern blot analysis. Alterations of the p53 gene (positive immunostaining for p53 protein in tumors with or without p53 gene mutations) in these 65 tumors were analyzed previously. None of the 65 tumors showed amplification or rearrangement of N-myc, c-myc, or N-ras oncogenes. The molecular analysis presented here demonstrates distinct variants of astrocytic tumors, with at least three genetic pathways leading to glioblastoma multiforme. One pathway was characterized by 43 astrocytomas with alterations in p53. Glioblastomas with p53 alterations may represent tumors that progress from lower-grade astrocytomas. This variant was more likely to show loss of chromosome 17p than tumors without p53 alterations (p < 0.04). Seventy-five percent of tumors with loss of one 17p allele demonstrated mutations in the p53 gene. Loss of chromosome 10 was associated with progression from anaplastic astrocytoma (13%) to glioblastoma (38%) (p < 0.04). Amplification of the EGFR gene was a rare (7%) but late event in tumor progression (p < 0.03). A second pathway was characterized by six astrocytomas without p53 alterations and may represent clinically de novo high-grade tumors. These tumors were more likely to show amplification of the EGFR gene (83%) than tumors with p53 alterations. Sixty percent of tumors with EGFR amplification also showed loss of chromosome 10; loss of chromosome 17p was infrequent in this variant. One or more alternative pathways were characterized by 16 astrocytomas without p53 alterations and with none of the genetic changes analyzed in this study. Glioblastomas are a heterogeneous group of tumors that may arise via multiple genetic pathways.     

Identification and molecular characterization of a small 11q23.3 de novo duplication in a patient with Rett syndrome manifestations

BACKGROUND AND STUDY AIMS: Modern fine-caliber endoscopes enable clinicians to directly visualize the pancreatic duct. They allow intraductal manipulation under optical control. We tried to evaluate the additional diagnostic potential of pancreatoscopy in assessing inconclusive intraductal pancreatic changes. PATIENTS AND METHODS: We prospectively performed 20 pancreatoscopies in 18 patients with inconclusive ductal abnormalities that had been previously investigated by computed tomography (CT) scan, abdominal ultrasound and endoscopic retrograde cholangiopancreatography (ERCP). The CHF-BP 30 (Olympus Optical Co., Japan) endoscope with an outer diameter of 3.1 mm and an instrumentation channel of 1.2 mm was used. Biopsies, cytological brushing and fluid collection were carried out, and the site of ductal abnormality was visualized. Endoscopic sphincterotomy (EST) was carried out in every patient prior to insertion of the pancreatoscope. RESULTS: Seven intraductal tumors were histologically confirmed, i.e. five intraductal papillary mucinous tumors and two adenocarcinomas. Benign appearance of the intraductal lesion plus negative histopathological examinations were confirmed by a follow-up of two years in eight patients. Five had chronic pancreatitis, and a further three had pancreatitis with strictures, blood clot obstruction, and idiopathic benign stricture, respectively. There were no complications with the exception of one bleeding episode after EST; no pancreatitis occurred. CONCLUSIONS: Pancreatoscopy is of diagnostic value in addition to CT, transabdominal ultrasound and ERCP in the differential diagnosis of poorly defined pancreatic lesions, particularly when assessing alterations of the ductal caliber without parenchymatous lesions.     

Genetic alterations at 5p15: a potential marker for progression of precancerous lesions of the uterine cervix

BACKGROUND: Development of uterine cervical cancer is preceded by preneoplastic proliferative changes in the cervical epithelium called "intra-epithelial neoplasia" or "dysplasia." The genetic basis of the origin and progression of such preneoplastic lesions is not known. By analysis of carcinomas for loss of constitutional heterozygosity (LOH), we have previously shown a high frequency of allelic loss in the short arm of chromosome 5 (5p), suggesting loss of a candidate tumor suppressor gene located in 5p and associated with the development of this tumor. PURPOSE: To further understand the role of genetic alterations that affect 5p in cervical carcinogenesis, we evaluated the status of microsatellite polymorphisms at five loci mapped to 5p14-ter in precancerous and cancerous lesions. METHODS: Biopsy specimens from two groups of patients were analyzed for genetic alterations affecting 5p. One group comprised 14 cases of precancerous lesions (i.e., dysplasias) and five cases of carcinoma in situ (CIS); the second group comprised 46 previously untreated patients with invasive carcinoma. Tumor and normal DNAs were analyzed by polymerase chain reaction for genetic losses and instability at five polymorphic microsatellite loci (D5S392, D5S406, D5S208, D5S117, and D5S432) mapped to 5p. RESULTS: LOH was observed in 25 (55.6%) of 45 informative invasive carcinomas, one (20%) of five cases of CIS, and three (21%) of 14 precancerous lesions. Among the loci tested, D5S406 (5p15.1-15.2) exhibited LOH in 12 (48%) of 25 invasive carcinomas, one (33%) of three cases of CIS, and three (60%) of five precancerous lesions, suggesting this to be the site in 5p of the novel candidate tumor suppressor gene. In addition, replication error-type alterations were noted in the 5p14-ter region in six (13%) of 46 invasive carcinomas, two (40%) of five cases of CIS, and three (21%) of 14 precancerous lesions. Instability affected D5S406 in eight (66.7%) of 12 instances that showed microsatellite instability. CONCLUSION: These observations suggest that allelic loss and microsatellite instability in the region of D5S406 may play a role early in the development of cervical carcinoma and identify the site of a candidate tumor suppressor gene. These genetic markers (allelic loss and microsatellite instability) may also define CIS and precancerous lesions at high risk for progression to invasive cancer. IMPLICATIONS: The future molecular cloning of the candidate tumor suppressor gene at 5p15.1-15.2 may provide new insights into the genetic mechanisms of cervical carcinogenesis. Analysis and clinical follow-up of a large cohort of prospectively ascertained cases of precancerous lesions would help to validate the usefulness of these markers.     

A case of double primary adenocarcinoma of the lung with multiple atypical adenomatous hyperplasia

A case of double primary adenocarcinoma of the lung with multiple atypical adenomatous hyperplasia (AAH) in a 77-year-old woman is reported. Histopathologically, in the resected left upper lobe of the lung, both cancers were diagnosed as well-differentiated papillary adenocarcinoma, and 161 lesions of AAH were also found. Both the cancer lesions and six AAH (greater than 3 mm in diameter) were examined with regard to immunoreactivity of carcinoembryonic antigen (CEA) and p53 gene product, microsatellite instability (MI) and loss of heterozygosity (LOH) on chromosome 9q and 17q by polymerase chain reaction (PCR). Although both cancers expressed CEA, they did not show clonal immunoreactivity for the p53 gene product. Atypical adenomatous hyperplasia expressed CEA weakly and showed no immunoreactivity for p53 gene protein. Both carcinomas showed LOH on chromosome 17q, and one of them showed LOH on chromosome 9q. In six AAH, LOH on chromosome 17q was detected in two tumors, and one of them also showed LOH on chromosome 9q. One AAH, which was negative for LOH on chromosome 17q and 9q, showed MI at D17S791. These results indicated that AAH is a clonal neoplastic lesion with genetic abnormalities and should be called intraepithelial pneumocyte neoplasia, and that each of the numerous papillary lesions in this case was considered to be an independent lesion.     

Overexpression of the p53 gene in primary and metastatic head and neck carcinomas

The p53 gene has been correlated with disease progression in a number of human malignancies, and p53 abnormalities are found in a high percentage of head and neck squamous cell carcinomas. The objectives of this study were 1. to correlate p53 expression with disease progression in squamous cell carcinoma of the head and neck (SCCHN), and 2. to determine whether there are site-specific differences in p53 expression. Primary lesions and/or lymph node metastases from 147 patients with invasive SCCHN were immunostained for p53 overexpression. Expression of p53 was similar (42% versus 43%) in primary lesions and lymph node metastases. Expression also did not vary significantly by site in the head and neck. In conclusion, increased p53 expression did not correlate with disease progression in our series of patients with invasive SCCHN. The finding of a lack of increased expression with disease spread to lymph nodes supports the belief that p53 alterations occur early in head and neck carcinogenesis.     

Superiority of extended en bloc esophagogastrectomy for carcinoma of the lower esophagus and cardia

The belief that transhiatal esophagogastrectomy results in the same survival as a more extensive en bloc resection was tested in 69 patients with carcinoma in the distal esophagus and gastric cardia. Preoperative and intraoperative staging defined three distinct subgroups of patients. Those with apparently limited disease and good general health (group I, n = 30) underwent en bloc resection. Those with apparently limited disease but poor physiologic reserve (group II, n = 16) underwent transhiatal resection, as did those with evidence of more advanced disease (group III, n = 23). Overall, survival was significantly better in the 30 patients who underwent en bloc resection (41%) than in the 39 patients who underwent transhiatal resections (14%; p < 0.001, log-rank). Clinical staging showed apparently limited disease in 46 patients (groups I and II). These groups differed only in the presence of poor physiologic reserve because the percentages of patients with tumors limited to the esophageal wall (group I 13/30, group II 6/16) and four or fewer lymph node metastases (group I 21/30, group II 15/16) at the time of pathologic staging were not significantly different. Survival after en bloc resection was, however, significantly better (41% versus 21%; p < 0.05, log-rank). According to the WNM system of pathologic staging, 19 patients had early lesions defined as intramural lesions associated with four or fewer lymph node metastases, 26 had intermediate lesions defined as either transmural or associated with more than four lymph node metastases, and 24 had late lesions defined as both transmural and associated with fewer than four lymph node metastases. Survival was significantly better in patients with early lesions after en bloc resection compared with transhiatal resection (75% versus 20%, p < 0.01), survival was also significantly better in patients with advanced lesions (27% versus 9%, p < 0.01). For intermediate lesions, the survival was similar (14% versus 20%), although the median survival after en bloc resection was longer (24 months versus 8 months).     

Loss of p16/INK4A protein expression in non-Hodgkin's lymphomas is a frequent finding associated with tumor progression

The CDKN2A gene located on chromosome region 9p21 encodes the cyclin-dependent kinase-4 inhibitor p16/INK4A, a negative cell cycle regulator. We analyzed p16/INK4A expression in different types of non-Hodgkin's lymphoma to determine whether the absence of this protein is involved in lymphomagenesis, while also trying to characterize the genetic events underlying this p16/INK4A loss. To this end, we investigated the levels of p16/INK4A protein using immunohistochemical techniques in 153 cases of non-Hodgkin's lymphoma, using as reference the levels found in reactive lymphoid tissue. The existence of gene mutation, CpG island methylation, and allelic loss were investigated in a subset of 26 cases, using single-strand conformational polymorphism and direct sequencing, Southern Blot, polymerase chain reaction, and microsatellite analysis, respectively. Loss of p16/INK4A expression was detected in 41 of the 112 non-Hodgkin's lymphomas studied (37%), all of which corresponded to high-grade tumors. This loss of p16/INK4A was found more frequently in cases showing tumor progression from mucosa-associated lymphoid tissue low-grade lymphomas (31 of 37) or follicular lymphomas (4 of 4) into diffuse large B-cell lymphomas. Analysis of the status of the p16/INK4A gene showed different genetic alterations (methylation of the 5'-CpG island of the p16/INK4A gene, 6 of 23 cases; allelic loss at 9p21, 3 of 16 cases; and nonsense mutation, 1 of 26 cases). In all cases, these events were associated with loss of the p16/INK4A protein. No case that preserved protein expression contained any genetic change. Our results demonstrate that p16/INK4A loss of expression contributes to tumor progression in lymphomas. The most frequent genetic alterations found were 5'-CpG island methylation and allelic loss.     

Methylation, a major mechanism of p16/CDKN2 gene inactivation in head and neck squamous carcinoma

We studied 11 head and neck squamous carcinoma (HNSC) cell lines and 46 primary tumors for p16 gene status by protein, mRNA, and DNA genetic/epigenetic analyses to determine the incidence, the mechanism(s), and the potential biological significance of its inactivation. Of the 11 cell lines, only 1 showed intact p16 and 10 lacked its protein and mRNA; DNA analysis of these 10 cell lines showed 2 homozygous deletions, 6 methylations at exon 1 and 2, and 2 with no detectable abnormalities. In primary tumors, 16 (34.7%) of the 46 showed detectable p16 protein and mRNA; of these, 12 had no DNA abnormalities and 4 had only exon 2 methylation. Loss of p16 expression was found in three tumors with concurrent mutation at exon 2 and methylation at exon 2 (two) and both 1 and 2 (one). Of the 30 tumors that lacked p16 protein, 27 also lacked mRNA, 1 had detectable p16 mRNA, and 2 failed RT-PCR amplification. Twenty-two of the thirty tumors showed DNA alterations and eight manifested no abnormalities; DNA alterations comprised 6 homozygous deletions, 2 concurrent mutations and methylation of exon 2, and 13 with methylation at exon 1 and exons 1 and 2 (12 with methylation only and 1 with mutation) at exon 1. Except for patients' gender (P = 0.02), no significant correlation between p16 and clinicopathological factors was observed. We conclude that in HNSC 1) intragenic p16 alterations are infrequent events, 2) methylation of exon 1 constitutes a common mechanism in silencing the p16 gene, 3) p16 inactivation may play an important role in the early development and progression of HNSC, and 4) no association between p16 alterations and conventional clinicopathological factors was noted in this cohort.     

Can knee joint proprioception by reconstruction of the anterior cruciate ligament be restored? A prospective longitudinal study

BACKGROUND: Usual ductal hyperplasia (UDH), atypical ductal hyperplasia (ADH), and ductal carcinoma in situ (DCIS) are risk factors for invasive breast cancer (IBC), suggesting that these lesions may be direct precursors of IBC. To identify genetic changes that may be important in the early development of precursor lesions and their progression to malignant or invasive disease, we examined 399 putative precursors (211 UDH, 51 ADH, 81 non-comedo DCIS, and 56 comedo DCIS) for loss of heterozygosity (LOH) at 15 polymorphic genetic loci known to exhibit high rates of loss in IBC. We also assessed the sharing of LOH by putative precursors and synchronous cancers. METHODS: The polymerase chain reaction was used to analyze DNA from microdissected archival specimens. RESULTS AND CONCLUSIONS: In hyperplasias from noncancerous breasts (i.e., without DCIS and/or IBC in analyses of hyperplasias), LOH at any given locus was rare (range, 0%-15%), although 37% of UDH and 42% of ADH lesions showed loss for at least one locus, suggesting that the development of hyperplasias can involve many different tumor suppressor genes. In DCIS from noncancerous breasts (i.e., without IBC in analyses of DCIS), LOH was common, with 70% of noncomedo lesions and 79% of comedo lesions showing at least one loss. In DCIS, substantial rates of loss (up to 37%) were observed at loci on chromosomes 16q, 17p, and 17q, suggesting that inactivated tumor suppressor genes in these regions may be important in the development of noninvasive breast cancer. When DCIS lesions from cancerous and noncancerous breasts were compared, substantially more LOH was observed in the cancerous breasts at a few loci (on chromosomes 2p, 11p, and 17q), suggesting that genetic alterations in these regions may be important in the progression to invasive disease. Among specimens harvested from cancerous breasts, 37% of UDH, 45% of ADH, 77% of noncomedo DCIS, and 80% of comedo DCIS lesions shared LOH with synchronous cancers at one locus or more, supporting the idea that the putative precursors and the cancers are genetically related.     

The effect of atropine on insulin stimulated gastric secretion and gastrin release

A 28-years-old patient with a palpable mass of two fist's size in the upper abdomen rapidly developed an obstructive jaundice. A pancreatic tumor was suspected and therefore ERCP was carried out. Unusual alterations caused by metastatic lesions of a post mortem diagnosed testicular teratoma narrowing and invading the common bile duct and displacing the main pancreatic duct were visualized.