Telomerase activity in malignant and benign renal tumors

OBJECTIVES: An important characteristic of malignant cells is their unlimited replicative potential, their immortality. In conferring this immortality, the enzyme telomerase is believed to play a crucial role. The detection of telomerase activity provides new knowledge regarding the biologic growth behavior of tumors and offers new diagnostic and therapeutic tools. METHODS: In the present study the sensitive TRAP assay (telomeric repeat amplification protocol) was used to examine 44 malignant renal tumors and 8 benign tumors of the kidney and 52 specimens of normal renal tissue for telomerase activity. RESULTS: Telomerase activity was detected in 63% of tissue samples obtained from histologically confirmed renal cell carcinomas. In cases of renal cell carcinoma restricted to the kidney, telomerase activity was detected in 58%. In cases in which tumor growth has progressed beyond the limits of the organ, telomerase activity was found in 69%. This stage dependence, however, did not reach statistical significance. No correlation to tumor grading was observed. Telomerase activity was found less frequent in chromophobe renal cell carcinomas. Neither the 8 benign renal tumors (4 oncocytomas and 4 angiomyolipomas) nor the specimens of normal kidney showed any evidence of telomerase activity. CONCLUSIONS: The proportion of remarkable slow-growing renal cell carcinomas showing telomerase activity is less than in other malignancies and may correlate with biologic growth behavior. Possible explanations include the presence of an alternative pathway, called ALT (alternative lengthening of telomeres) and an association with the loss or presence of the telomerase suppressor on the short arm of chromosome 3. Prolonged follow-up will be of special interest to determine whether lack of telomerase activity predicts favorable outcome.     

FOCAL INTRATUMORAL HETEROGENEITY FOR TELOMERASE ACTIVITY IN HUMAN PROSTATE CANCER

PURPOSE: The value of telomerase activity as a marker in clinical decision-making is closely related to how representative the analysis of a small tumor sample is for the whole tumor. We therefore evaluated the intratumoral distribution pattern of telomerase activity in prostatic carcinomas. MATERIALS AND METHODS: From 50 prostate cancer patients treated with radical prostatectomy, telomerase activity was determined using the telomeric repeat amplification protocol (TRAP assay). Comparative analysis of at least two separate cancer areas from a single tumor was performed in 42 cases. RESULTS: Telomerase activation has been demonstrated in 90% of the prostatic carcinomas. Focal intratumoral heterogeneity was found in 38.1% of the tumors with at least two different areas examined. Telomerase positivity of all samples from one given tumor was detected in 50%, telomerase negativity of all samples in 11.9%. A heterogeneous telomerase activity pattern was more frequently detected in tumors with a Gleason score < or = 7 than in those with a Gleason score > 7. Furthermore, there was an increase in the proportion of homogeneously telomerase-positive tumors with increase in severity of the Gleason score. The differences reached statistical significance. Telomerase activity was also detected in non-cancerous prostatic tissue samples. CONCLUSIONS: Telomerase activation is nearly ubiquitous in prostatic carcinomas, although a heterogeneous telomerase activity pattern within tumors might produce a false-negative result in the telomerase activity assay. This limits the value of telomerase activity assays for diagnostic means. There is evidence for a shift from telomerase-negative prostate cancer tissue toward telomerase positivity during the progression process of prostate cancer. The relatively high proportion of telomerase-positive nonmalignant prostatic tissue samples argues against cancer-specificity of telomerase activation.     

Detection of telomerase activity in breast masses by fine-needle aspiration

Background: Telomerase is an RNA-dependent DNA polymerase that compensates for the telomere shortening that occurs in its absence. Reactivation of telomerase is thought to be an important step in cellular immortalization, and recent studies have indicated that telomerase activity is often detected in primary human malignancies. The clinical implications of telomerase activity in human tumors are currently under investigation. Methods: Eighty-nine samples (46 FNAs and 43 gross tissue biopsies) from 44 patients with breast masses were analyzed prospectively for the presence of telomerase activity by a modification of the telomere repeat amplification protocol (TRAP). All samples were obtained directly from the excised mass at the time of specimen removal in the operating room. Results: Telomerase activity was detected in 17 of 19 (90%) FNA samples and 15 of 18 (83%) invasive breast cancer tissue biopsies. Telomerase was also detected in 9 of 16 (56%) FNAs and 8 of 15 (53%) tissue biopsies from 16 fibroadenomas. Other benign proliferative lesions (n=5) did not have detectable telomerase activity in either FNA or tissue specimens. FNA-TRAP results correlated with the gross tissue specimen TRAP results in 95% of all cases. Conclusion: The FNA-TRAP assay for telomerase detection is a highly sensitive and accurate method for the detection of telomerase activity in breast masses. Future application of these techniques should facilitate evaluation of telomerase as a tumor marker in the clinical management of breast and other solid malignancies. These authors contributed equally to this work.     

Telomerase activity is a useful marker to distinguish malignant pancreatic cystic tumors from benign neoplasms and pseudocysts

BACKGROUND: Pancreatic serous cystadenoma, mucinous cystic neoplasms, ductal adenocarcinoma with cystic change, and pseudocysts are a spectrum of pancreatic cystic lesions. Their management strategy and prognosis are extremely diverse. Imaging study, cytology, and analysis of the tumor markers of cyst fluid are not always reliable in differentiation of these disease entities. MATERIALS AND METHODS: Fifteen patients with pancreatic cystic neoplasms (including six mucinous cystadenocarcinomas, two mucinous cystic neoplasms with borderline malignancy, two mucinous cystadenomas, and five serous cystadenomas), 4 patients with pancreatic ductal adenocarcinomas with cystic change, and 10 patients with pseudocysts were studied. Echo-guided or computed tomography-guided biopsies of pancreatic cystic lesions and their normal counterparts were conducted on all patients prior to operation or other management. The specimens were assayed for telomerase activity by using TRAP (telomere repeat amplification protocol). The level of telomerase activity in each specimen was semiquantitated as strong, moderate, weak, and none. The final diagnoses were made from histopathological examination of surgically resected or biopsied specimens. The efficacy of telomerase activity as a tumor marker to predict malignancy of pancreatic cystic lesions was evaluated. RESULTS: Three of the four pancreatic ductal adenocarcinomas with cystic change had strong or moderate telomerase activity; four of the six mucinous cystadenocarcinomas had moderate or weak telomerase activity; one of the two mucinous cystadenomas with borderline malignancy had weak telomerase activity; and none of their normal counterparts had detectable telomerase activity. In contrast, none of the two mucinous cystadenomas, five serous cystadenomas, and 10 pseudocysts had detectable telomerase activity. Based on these results, the sensitivity of telomerase activity for prediction of malignancy or premalignancy of pancreatic cystic lesions was 67%, the specificity was 100%, and the positive and negative predictive values were 1.0 and 0.81, respectively. The overall accuracy was 86%. CONCLUSIONS: The differential expressions of telomerase activity have been detected specifically in malignant and premalignant pancreatic cystic tumors, but not in benign cystic neoplasms or pseudocysts. The implications of these results are that telomerase activation takes part in the malignant transformation of pancreatic cystic neoplasms and that telomerase activity is a useful marker to distinguish malignant pancreatic cystic tumors from benign neoplasms and pseudocysts.     

Telomerase activity in skeletal sarcomas

Background: Telomerase is a ribonucleoprotein that adds TTAGGG nucleotide repeats onto the ends of eukaryotic chromosomes to maintain telomere integrity. Somatic cells do not express telomerase and stop dividing when the chromosomal ends are shortened critically after many cell divisions. Immortal cell lines and cancer cells apparently have telomerase activity that contributes to an unlimited number of cell cycles. The purpose of our study is to investigate whether telomerase activity is expressed in primary malignant tumors of the skeletal system when compared to adjacent normal tissue. Methods: Fresh tumor and normal tissue was collected from 14 patients (10 males, 4 females; age range, 8 to 76 years) and protein extraction performed. The tumors included seven osteosarcomas (three examined before and after chemotherapy), two chondrosarcomas, two spindle cell tumors, one hemangiopericytoma, one chordoma, and one adamantinoma. Telomerase activity was analyzed by using a highly sensitive polymerase chain reaction (PCR)-based assay (telomere repeat amplification protocol [TRAP]). Results: Telomerase activity was found in 8 of 14 sarcoma patients (57%) using the TRAP assay. Compared to HeLa cell extract (positive control), telomerase activity in the tumor specimen ranged from 0 (in osteosarcoma) to 11.7% (in hemangiopericytoma). There was variation in the number of telomeric repeats generated by telomerase. At least five telomeric bands (e.g. 50, 56, 62, 68, 74 bp) in a ladder pattern had to be present before telomerase activity was considered positive in our analysis. Conclusions: Telomerase activity may be an oncogenic sustaining event helping to maintain the transformed phenotype seen in malignant tumors of the bone. The degree of telomerase activity varies among skeletal malignancies, but was less than that observed in HeLa cells. The majority of osteosarcomas showed no telomerase activity.     

Expression of telomerase activity in thymoma and thymiccarcinoma tissues; a clinicopathological study

BACKGROUND: Telomerase is a nucleoprotein complex that caps the physical termini of all eukaryotic chromosomes. It is suggested that telomerase play important roles in unlimited cell division acquisition of the malignant phenotype. We studied the relation of telomerase activity in thymoma and thymic carcinoma to the clinicopathological features of these lesions. METHODS: Tissue specimens were surgically resected from patients with thymoma and thymic carcinoma. Telomerase activity was evaluated according to a modified telomeric repeat amplification protocol (TRAP) assay. RESULTS: Telomerase activity was detected in all thymic epithelial tumors. The activity (mean +/- SD: unit/microgram.protein) in thymoma (n = 17) was significantly higher than that in thymic carcinoma (n = 7) [431.8 +/- 400.1 vs. 68.8 +/- 39.8: p < 0.01]. Telomerase activities in thymoma and thymic carcinoma were significantly higher than that in primary lung adenocarcinoma (33.5 +/- 39.2: n = 47), studied as control (p < 0.01). In patients with thymoma, telomerase activity did not correlate with tumor stage according to Masaoka classification (p = 0.776). In patients with thymic carcinoma, however, telomerase activity positively correlated with tumor stage (p = 0.02). In thymoma, telomerase activity positively correlated with the ratio of induced lymphocytes according to Rosai's classification (p = 0.045). CONCLUSION: In thymoma, telomerase activity reflects the presence of immature T-cell lymphocytes in tumor tissue rather than tumor stage or malignant phenotype. In thymic carcinoma, telomerase activity derived directly from cancer cells may relate to tumor stage.     

The association between telomerase, histopathological parameters, and KI-67 expression in breast cancer.

BACKGROUND: Telomerase is a ribonucleoprotein enzyme that appears to play an important role in carcinogenesis. Telomerase reactivation seems to be associated with immortalization and malignancy. METHODS: Using a polymerase chain reaction (PCR)-based assay known as the TRAP (telomeric repeat and amplification protocol) assay, we examined telomerase activity in 60 breast specimens prospectively collected from 39 patients undergoing elective breast surgery in our center. The specimens included adjacent noncancerous breast (n = 21), benign breast disease (n = 5), and infiltrating carcinoma (n = 34). Ki-67 expression was determined in 32 invasive breast cancer specimens using immunohistochemistry techniques. The histopathological features were determined by light microscopy by an experienced breast pathologist. RESULTS: Telomerase activity was detected in 24 (71%) of 34 infiltrating carcinomas. None of the adjacent noncancerous specimens nor the benign breast lesions expressed telomerase activity. Telomerase reactivation was significantly associated with nodal metastasis and Ki-67 expression. There was no significant association between telomerase activity and menopausal status, tumor grade, or tumor size. CONCLUSIONS: Telomerase reactivation is associated with the acquisition of malignancy in the human breast. Telomerase activity is significantly associated with nodal metastasis and cellular proliferation as measured by Ki-67 expression in human breast cancer.     

TRAP银染法检测端粒酶在胃癌组织中的表达

目的了解胃癌组织中端粒酶表达的状况及其临床意义,研究非放性 TRAP 检测端粒酶的可行性。方法用 TRAP 银染法检测58例胃癌及相应患者的正常胃粘膜,12例胃腺瘤和9例胃溃疡组织的端粒酶表达情况。结果 58例胃癌组织中49(84.5％)例端粒酶表达阳性,正常粘膜无一例检测到端粒酶活性(P<0.001),12例胃腺瘤,9例胃溃疡组织中各有1例检测到端粒酶活性。胃癌组织端粒酶的表达与年龄、肿瘤大小、分化程度、浸润深度、淋巴结转移及 TNM 分期等临床病理参数无明显相关(P<0.05)。结论端粒酶是一种较理想的胃癌肿瘤标记物,TRAP 银染法是一种值得推广的检测端粒酶活性的方法。     

Telomerase activity in touch-imprint cell preparations from fresh prostate needle biopsy specimens.

OBJECTIVE: To evaluate whether it is possible to detect telomerase activity in cells exfoliated from prostate biopsies immediately before fixation. METHODS: A total of 115 transrectal biopsies of prostate tissue from 49 patients were touch-imprinted on an RNase-free microscope slide and then fixed. Touch imprints were immediately frozen and used to extract telomerase. Telomerase activity was determined by a telomeric repeat amplification protocol (TRAP) using a PCR-ELISA method. Inflammation and epithelial cells in each biopsy were quantitated by image cytometry. RESULTS: A total of 90/115 extracts had a proteic content suitable for analysis. Telomerase activity was detected in 18/26 (70%) carcinomas, 2/9 (22%) low-grade prostatic intraepithelial neoplasia (PIN) lesions, and 1/3 (33%) high-grade PIN lesions. In 4 of 7 patients with telomerase-positive tumors, telomerase activity was also found in a distant site devoid of morphologically detectable cancer cells. Telomerase activity was detected in touch imprints from fragments with less than 1 mm(2) of epithelial tissue, and was not associated with the extent of inflammation. CONCLUSIONS: From the technical stand point, the touch-imprint method may provide a useful adjunct for telomerase detection in prostate biopsies. With this procedure the bioptic fragment is left intact for histological examination. Diagnostically, the presence of telomerase activity in sites distant from the original tumor might suggest the presence of tumor cells that are morphologically undetectable.     

胃癌与端粒酶活性表达及DNA倍体关系的研究

目的　揭示胃癌与端粒酶活性及DNA倍体的关系。方法　检测 30例胃癌标本 ,同时取无瘤残端作为对照。端粒酶检测采用端粒重复扩增 酶联免疫吸附法 (TRAP ELISA法 )。DNA倍体的测定采用流式细胞术 ,一步法检测DNA含量。结果　肿瘤瘤体端粒酶阳性率 83 3% (2 5 / 30 ) ,无瘤残端端粒酶阳性率 3 3%(1/ 30 ) (P <0 .0 5 ) ;端粒酶阳性瘤体平均直径 6 5cm ,阴性瘤体平均直径 3 6cm(P <0 .0 5 ) ;端粒酶阳性肿瘤淋巴转移率 5 3 3% (16 / 30 ) ,阴性者无淋巴转移 (0 / 5 ) (P <0 .0 5 ) ;端粒酶阳性肿瘤中异倍体肿瘤占 5 6 0 % (14/2 5 ) ,而端粒酶阴性者无异倍体出现 (P <0 .0 5 )。结论　胃癌端粒酶活性升高 ,端粒酶阳性肿瘤瘤体大 ,淋巴转移率高 ,且异倍体发生率高 ,预后差。提示端粒酶的激活与胃癌的发生发展有密切关系。     

Detection of telomerase activity in bronchial lavage as an adjunct to cytological diagnosis in lung cancer.

OBJECTIVE: Definitive diagnosis of lung cancer with conventional methods may sometimes be difficult in clinical practice. Telomerase is a ribonucleoprotein DNA polymerase that maintains the telomeric region of chromosomes during successive rounds of cell division. Telomerase activity in body cavity fluids has been advocated to be a potential diagnostic marker for malignancy. We investigated the diagnostic value of telomerase activity in bronchial lavage samples of patients undergoing diagnosis of lung cancer. METHODS: A total of 29 bronchial lavage samples were collected from patients in whom the diagnosis was confirmed with cytological and/or histological examinations. Patients were classified as lung cancer patients (Group 1, n = 22) and patients with benign disease (Group 2, n = 7). Telomerase activity was determined with polymerase chain reaction-based TRAP (The telomeric repeat amplification protocol) assay. RESULTS: Cytological examination was diagnostic in 12 (54.5%) of 22 patients in Group 1, and in all seven patients of Group 2 (P = 0.063). Telomerase activity was positive in 16 (72.7%) of Group 1 patients, while it was positive in only 1 (14.3%) sample of a lung abscess in Group 2 (P = 0.011). The sensitivity rate of cytological examination when combined with telomerase activity (81.8%) was significantly greater than that of cytological examination alone (54.5%) (P = 0.031). The sensitivity and specificity of telomerase activity were 72.7 and 85.7%, respectively. Telomerase activity had a positive predictive value as 0.94 and negative predictive value as 0.50. Diagnostic accuracy of telomerase activity was 75.8%. CONCLUSION: Telomerase activity in bronchial lavage is a highly sensitive diagnostic biomarker for malignancy and a potential complementary diagnostic technique to cytological examination in the diagnosis of lung cancer.     

Semi-quantitative analysis of telomerase activity of exfoliated cells in urine of patients with urothelial cancers: Causative factors affecting sensitivity and specificity

We previously reported that detection of telomerase activity in urinary exfoliated cells obtained from urothelial cancer patients by telomeric repeat amplification protocol (TRAP) assay is a more sensitive method of diagnosis than conventional urine cytologic examination, particularly in patients with grade 1 tumors. To establish this method as a noninvasive screening test for the diagnosis of urothelial cancers, we performed the semi-quantitative analysis of telomerase activity using Telomerase PCR ELISA?. Spontaneous voided urine samples were obtained from 65 urothelial and 58 non-urothelial cancer patients. When the mean + 2 standard deviation of telomerase activity in urine sediments of non-urothelial cancer patients was arbitrarily determined as a cut-off, the sensitivity of TRAP enzyme-linked immunosorbent assay (ELISA) and the conventional cytology were 57% and 35%, respectively. Detection rate was significantly higher in semi-quantitative TRAP assay than in conventional cytologic examination in grade 1 cancer patients (52% vs. 5%, p = 0.00195). False positives were detected in 5% of non-urothelial cancer patients without pyuria and in 11% of non-urothelial cancer patients with pyuria (p = 0.395). Telomerase activity was enhanced in some cases after phenol extraction or extracting epithelial cells by using Dynabeads of macroscopic hematuria and pyuria, indicating that hematuria and pyuria might contribute to false negatives. In conclusion, the TRAP-ELISA method is superior to the standard TRAP assay in quantitativeness and simplicity of the experimental procedure. Detection of telomerase activity in urine sediments is particularly useful for the diagnosis of low-grade tumors. However, telomerase activity in patients with high grade tumors often might be underestimated due to the excessive amount of exfoliated epithelia with necrotic tissues, hematuria, and pyuria.     

Telomerase activity in diagnosis of bladder cancer

OBJECTIVE: Telomerase is an enzyme that can reconstitute the ends of chromosomes after cell division and thus circumvent the damage that occurs in normal adult somatic cells during successive mitotic cycles. Immortal cells have short but stable chromosomes and increased telomerase activity. Transitional cell carcinoma (TCC) has only a few useful markers of diagnostic or prognostic importance. The objectives of this study were to determine whether there was a correlation between telomerase activities and the grade or stage of TCC and whether the activity of the enzyme could serve as a biochemical marker of this tumor. MATERIAL AND METHODS: Telomerase activity was determined by examining, using a polymerase chain reaction-based assay designed using the telomeric repeat amplification protocol (TRAP), urine cell pellets obtained from 42 bladder cancer patients, 18 patients with primary hematuria, 19 patients with benign urologic disease, 14 patients with urologic malignancies other than TCC and 20 healthy volunteers. RESULTS: Telomerase activity was found in 24/31 patients with bladder tumors (77.4% sensitivity) and in 5/77 patients without tumors (93.5% specificity). No correlation was found between telomerase activity and the grade or stage of the tumor. Although none of the urine cell pellets obtained from the 20 healthy volunteers demonstrated telomerase activity, positive telomerase activity was found in two subjects in the benign urologic disease group and in three subjects in the other urologic malignancy group. It was demonstrated that gross hematuria was the cause of false-negative results in six of the nine patients (66.7%). but washing the pellets four times and diluting them before the TRAP assay solved this problem. CONCLUSION: These results indicate that telomerase activity may be a promising marker for TCC but the technical aspects of the technique must be improved before it is used in routine clinical practice as a standard method. False-negative results obtained using gross hematuric urine should be carefully reevaluated and cell pellets should be washed again and diluted before analysis.     

Telomerase Activity in Giant Cell Tumors of Bone

Background A giant cell tumor of bone (GCT) is a histologically benign neoplasma that has an unpredictable pattern of biological aggressiveness. In the present study, we investigated whether there was a correlation between telomere length or the levels of telomerase activity and other clinical features of GCTs, for the possible use of these factors as parameters of aggressiveness or prognosis. Methods In 16 surgically resected GCTs specimens, telomere length was assessed by terminal restriction fragments by Southern blot analysis. Telomerase activity was measured by a semiquantitative polymerase chain reaction–based telomeric repeat amplification protocol assay. Results Telomere length reduction was observed in 69% of the GCT samples. The telomere lengths of tumors were significantly shorter than those of normal tissue (P = .008). The mean telomere length of grade 3 tumors was significantly shorter than those of grade 1 and 2 tumors (P = .038). Telomerase activity was detected in 81% of tumor samples. The level of telomerase activity in tumors with local recurrence was significantly higher than in tumors without local recurrence (P = .011). Conclusions These results suggest that telomere length correlates with roentgenographic grade as a result of the frequency of cell division, and high telomerase activity indicates the aggressiveness of GCTs.     

胰腺癌组织中端粒酶活性的表达

目的　探讨端粒酶活性与胰腺癌之间的关系 ,评价其作为胰腺癌诊断新的肿瘤标志物的可能性。方法　采用重复片段扩增SYBRGreen染色法 ,对 42例胰腺癌癌患者癌组织及其癌旁组织的端粒酶活性进行检测。结果　胰腺癌组织中端粒酶阳性率为 80 .9% (3 4/4 2 ) ,而在癌旁组织中仅 7.1% (3 /4 2 )表达端粒酶活性 ,胰腺癌组织端粒酶活性显著高于癌旁组织 (P <0 .0 0 1)。端粒酶活性的表达与胰腺癌组织的肿瘤大小、淋巴结转移、病理学临床分期及分化程度相关。结论端粒酶活性是特异性较强的恶性肿瘤分子标志物 ,其检测有可能成为胰腺癌诊断和预后判断的有效指标     

Duodenal-preserving resection of the head of the pancreas and pancreatic head resection with second-portion duodenectomy for benign lesions,low-grade malignancies,and early carcinoma involving the periampullary region

HYPOTHESIS: Duodenal-preserving resection of the head of the pancreas (DPRHP) and pancreas head resection with segmental duodenectomy (PHRSD) can be alternatives to standard pancreaticoduodenectomy for benign periampullary lesions. DESIGN: Retrospective analysis of patients requiring surgery for benign and borderline malignant tumors of the periampullary region. SETTING: Tertiary care referral center. PATIENTS: Duodenal-preserving resection of the head of the pancreas (n = 8) and PHRSD (n = 7) were performed in 15 patients with a preoperative diagnosis of benign and borderline malignant tumors of the periampullary region (ie, 11 pancreas head lesions [2 intraductal papillary mucinous tumors, 4 serous cystadenomas, 2 insulinomas, 1 epidermal cyst, 1 metastatic renal cell carcinoma, 1 nonfunctioning islet cell tumor/parapaillary] and 4 duodenal lesions [3 adenomas and 1 adenocarcinoma]). MAIN OUTCOME MEASURES: Surgical factors (operation time and blood loss), postoperative complication, postoperative pancreatic insufficiency (eg, development of diabetes mellitus and steatorrhea or elevated stool elastase values), weight change, and recurrence of disease. RESULTS: No differences were noted in the mean operation time and estimated blood loss between the 2 procedures. Major postoperative complication constituted the following: bile duct stricture (n = 1) in DPRHP and delayed gastric emptying (n = 1) and postoperative bleeding (n = 1) in PHRSD. Newly developed diabetes mellitus occurred in 1 patient. Exocrine pancreatic insufficiency (steatorrhea) was observed in 1 patient after PHRSD. Patients with early duodenal carcinoma and intraductal papillary mucinous tumors with a borderline malignancy are still alive without evidence of recurrence. There was no hospital or long-term mortality. CONCLUSIONS: Duodenal-preserving resection of the head of the pancreas is recommended first for a benign or low-grade, early malignant pancreatic head lesion; PHRSD can be an option for a lesion of the ampullary-parapapillary duodenal area as well as the pancreatic head. Duodenal-preserving resection of the head of the pancreas can be converted to PHRSD if ischemia of the second portion of the duodenum occurs. We found benign periampullary lesions could be conservatively treated with DPRHP and PHRSD, which could substitute for classic pancreaticoduodenectomy.     

Non ductal-adenocarcinoma neoplasms of the pancreas

Pancreatic Non Ductal-Adenocarcinoma Neoplasms (PNDAN) represent about 20% of pancreatic and periampullary tumors and should be considered in differential diagnosis with ductal adenocarcinoma in the presence of isolated pancreatic mass. From January 1992 to December 1998, 238 patients were operated on for pancreatic and periampullary masses. Fifty-five patients had PNDAN: 24 endocrine tumors, 7 serous cystadenomas, 6 intraductal papillary-mucinous tumors, 5 acinar carcinomas, 4 mucinous cystadenomas, 3 metastatic tumors, 2 cystic papillary tumors, 2 solid cystadenocarcinomas, 1 neurilemmoma, and 1 pancreatoblastoma; 19 were benign and 36 were malignant or borderline tumors. A correct preoperative diagnosis was obtained in 58% of the cases. In all other cases, diagnosis was achieved intraoperatively. Major (18 pancreaticoduodenectomies, 17 left splenopancreatectomies, 1 total pancreatectomy) and minor resections (5 central pancreatectomy, 10 enucleations) were performed; curative surgical operations were carried out on 39/55 patients (curative resectability: 71%). Operative mortality and morbidity were 1.8% and 21.8%, respectively. Three and 5-year actuarial survival for malignant or borderline PNDANs are 65% and 40% versus 31% (3-year) for ductal adenocarcinoma of pancreatic head treated by pancreaticoduodenectomy (p-value = 0.03). We believe that pancreatic masses that are not ductal adenocarcinomas, can be aggressively resected even if large in size, resulting in a better outcome than ductal adenocarcinoma itself.     

Detection of telomerase activity in esophageal squamous cell carcinoma and normal esophageal epithelium

Background/aims: Relatively little has been reported about the telomerase activity of esophageal squamous cell carcinoma or normal esophageal epithelium. In this study, we have evaluated whether telomerase activity is a useful marker for detecting malignancies in the esophagus. Patients/methods: Esophageal carcinomas and normal esophageal tissues adjacent to carcinomas were obtained from 52 surgically treated, unselected patients, and normal esophageal epithelium from 11 non-cancerous patients were obtained by means of biopsy. The telomeric repeat amplification protocol (TRAP) assay was used for detection of telomerase activity in these samples. The incidence of detection of telomerase activity in esophageal carcinoma was compared with that of telomerase activity in normal esophageal epithelium. Moreover, the clinicopathological characteristics of telomerase-positive tumors were compared with those of telomerase-negative tumors. Results: Of the 52 carcinomas, 40 (77%) had detectable telomerase activity. However, telomerase activity was detected in 45 of 52 (87%) normal tissue samples adjacent to carcinomas and in 8 of 11 (73%) normal esophageal epithelium from non-cancerous patients. In esophageal cancer, no significant difference was detected in the clinicopathological findings between the telomerase-positive and -negative cases. Conclusion: These results indicate that not only esophageal squamous cell carcinomas but also normal esophageal epithelium show strong telomerase activity. Thus, telomerase activity may not be a good marker for the detection of carcinoma in the esophagus. Received: 16 March 1999 Accepted: 8 July 1999     

胃癌端粒酶活性检测的临床意义

目的　探讨端粒酶在胃癌组织中的活性及其临床意义。方法　应用银染 Ｔ Ｒ Ａ Ｐ 方法检测９４ 例胃癌组织、１２ 例胃腺瘤、９ 例胃溃疡和５８ 例癌旁正常胃粘膜中端粒酶活性。结果　９４ 例原发胃癌组织中检出端粒酶阳性８１ 例,阳性率为８６ ．２ ％ 。正常粘膜无１ 例检测到端粒酶表达,１２ 例胃腺瘤有１例表达端粒酶阳性,在９ 例胃溃疡组织中有１ 例检测到端粒酶表达,１２ 例胃腺瘤有１ 例表达端粒酶阳性,在９ 例胃溃疡组织中有１ 例检测到阳性端粒酶表达。胃癌与正常粘膜组端粒酶表达率差异有显著性（ Ｐ＜ ０ ．００１） 。端粒酶活性与肿瘤大小、分化程度、浸润深度、淋巴结转移和 Ｔ Ｎ Ｍ 分期无明显相关（ Ｐ＞ ０ ．０５） 。结论　测定胃癌端粒酶活性对胃癌的诊断有一定意义。