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Expression of cell cycle regulatory proteins and analysis of apoptosis in normal nasal mucosa and in nasal polyps.

BACKGROUND: The etiopathogenesis of nasal polyps still is to be clarified. Although hyperplasia is a typical feature of these pathological processes, little attention has been paid to specific aspects of cellular growth in polyps. We have evaluated the expression and localization of some of the regulatory proteins that direct the cell through the specific sequence of events culminating in mitosis or apoptosis in nasal polyps. METHODS: Twenty samples of nasal polyps and 20 samples of normal nasal mucosa have been analyzed for apoptotic index by detecting the DNA 3'OH ends deriving from DNA fragmentation. Moreover, they have been evaluated by immunohistochemical staining for expression of Ki-67, cyclins A and B1, p53, p21, p27, murine double minute clone 2, and Bcl-2. RESULTS: We have identified a greater proportion of proliferating cells in the lining epithelial cells of the polyps when compared with the normal mucosa as stained with anti-Ki-67 antibodies. An overexpression of p53, MDM2, and Bcl-2 and an increased apoptosis were observed in nasal polyps compared with the normal mucosa, whereas no variation of p27 expression was observed. The p21 and cyclins A and B1 were rarely expressed in both pathological and normal tissue. CONCLUSION: The p53-based control system of cell cycle progression appears to be altered in nasal polyps, potentially leading to an abrogation of the DNA damage checkpoint. Evaluation of the expression of the regulatory proteins that direct the cells throughout their cycle in nasal polyps may allow a better understanding of the biological behavior and clinical outcome of these benign pathological entities.

Adult↗

Demographic and anatomical survey of colorectal polyps in an Iranian population.

OBJECTIVE: Asian countries generally have low incidences of colorectal cancers (CRCs). One approach to prevention is based on recognition and removal of polyps. The aim of this study was to determine basic demographic features, anatomic distribution and characteristics of colorectal polyps in a local Asian population for comparison with western data. METHODS: We here performed a retrospective chart review of 194 patients with colorectal polyps detected by endoscopy [total colonoscopy in 136 cases (73.1%), and flexible sigmoidoscopy in the remainder] during 1992-2005, focusing on descriptive statistics for categorical variables, including distribution pattern and histology. Cold biopsy in 14 cases, piecemeal endoscopic resection in 5 patients, and usual snare polypectomy in the remainder were performed. Patients with polyposis syndromes were excluded from the analysis. RESULTS: The average age of patients was 43.2 yr (range 2-80) with 71% being males. Most of the polyps were presented in 5th decade (p=0.029). A total of 32 (17.2%) had synchronous proximal polyps (15% adenomas), and 154 cases had solitary polyps. The vast majority of the polyps were left sided and the most frequent type was adenoma (63%), with a villous component in 37.1%. Coexistent cancer was seen in 10.9% of cases. CONCLUSION: In this Iranian population, the majority of polyps are left sided. The incidence of adenomas and their histology appear comparable to data for western patients, but with a significantly lower rate for synchronous neoplastic lesions.

Adolescent↗

[Ureteral polyp resected with a ureteroscope: report of two cases].

Two cases of ureteral polyp resected by a transurethral approach are presented. Case 1: A 70-year-old woman was referred to our clinic because of hydronephrosis incidentally found. Excretory urography demonstrated a filling defect with a long and round smooth contour in the left lower ureter without hydroureter. Urine cytology was negative for malignant cells. Under the clinical diagnosis of left ureteral polyp, polyp was resected transurethrally. The pathological diagnosis was fibroepithelial polyp. Case 2: A 59-year-old woman was referred to our clinic with a chief complaint of macroscopic hematuria. Excretory urography revealed a filling defect with a long and round smooth contour in the left upper ureter. Because urine cytology was negative for malignant cells, left ureteral polyp was suspected. After the operation by tranthurethral approach, the pathological diagnosis was fibroepithelial polyp. No intraoperative complication was observed in either case. Ureteral polyps resected by a transurethral approach are relatively rare. We reviewed and discussed 46 cases of ureteral polyp resected transurethrally, reported in Japan including our two cases.

Aged↗

Reliability of the reported size of removed colorectal polyps.

BACKGROUND: The size of colorectal polyps is important in the clinical management of these lesions. AIM: To audit the accuracy in calculating the size of "polyps" by various specialists. MATERIALS AND METHODS: Eighteen pathologists and four surgeons measured, with a conventional millimetre ruler, the largest diameter of 12 polyp phantoms. The results of two independent measurements (two weeks apart) were compared with the gold standard-size assessed at The Royal Institute of Technology, Sweden. RESULTS: Thirty-one percent (83/264-trial 1) and 33% (88/264-trial 2) of the measurements underestimated or overestimated the gold standard size by >1 mm. Of the 22 experienced participants, 95% (21/22-trial 1) and 91% (20/22-trial 2) misjudged by >1 mm the size of one or more polyps. Values given by 13 participants (4.9%) in trial 1 and by 15 participants (5.7%) in trial 2, differed by > or = +/-4 mm from the gold standard size. In addition, a big difference between the highest and the lowest values was recorded in some polyps (up to 11.4 mm). Those disparate values were regarded as a human error in reading the scale on the ruler. CONCLUSION: Using a conventional ruler (the tool of pathologists worldwide) unacceptably high intra-observer and inter-observer variations in assessing the size of polyp-phantoms was found. The volume and the shape of devices, as well as human error in reading the scale of the ruler were confounding factors in size assessment. In praxis, the size is crucial in the management of colorectal polyps. Considering the clinical implications of the results obtained, the possibility of developing a method that will allow assessment of the true size of removed clinical polyps is being explored.

Colonic Diseases↗

Cancer-associated alterations of blood group antigen expression in human colorectal polyps.

Human colorectal carcinoma tissues may exhibit several patterns of altered blood group substance (BGS) expression: reappearance of A, B, H, or Lewisb antigens in distal colon; deletion of BGS in the proximal colon with or without precursor substance accumulation; and incompatible BGS expression in proximal or distal colon. The present study evaluated these cancer-associated alterations in colorectal polyps with different malignant potential. With respect to ABH antigens, hyperplastic polyps (HPs), considered to have no malignant potential, did not exhibit incompatibility and only a few cases demonstrated BGS reappearance or deletion. Adenomatous polyps (APs) however, frequently reexpressed ABH antigens or expressed incompatible BG-A or B in 27% of polyps; one specimen demonstrated BG-B deletion. Precursor expression was not found in HPs but was frequently observed in APs. Reappearance of ABH in distal polyps was significantly correlated with increasing grade of dysplasia, but was not significantly correlated with polyp size or histological type. With respect to Lewis antigen expression, Lewisb reappearance occurred in almost every distal polyp, and Lewisa-Lewisb coexpression was also quite common. Lea deletion was frequently noted, especially in HP, but the significance of this finding is unclear. This study indicates that several antigenic alterations that occur in colorectal cancer tissues also appear in premalignant polyps, and often in early stages of the neoplastic process. The observation that incompatible expression of BG-A or B occurs only in AP and cancer tissues (as well as mucosa adjacent to cancer) but not in fetal colonic mucosa, adult normal colonic mucosa, or HP, suggests that this may be a cancer-specific phenomenon.

ABO Blood-Group System↗

Colorectal polyps in the Upper Galilee.

This study of colorectal polyps is based on 129 patients in whom 241 colorectal polyps were diagnosed and excised by colonoscopy in the Gastroenterology Unit of a hospital in the Upper Galilee, Israel, between 1 July 1984 and 30 June 1987. The male:female ratio was 2:1. Anemia was demonstrated in 7% and positive Hemoccult II test (Smith Kline, USA) in 64%. The types of polyp were 58% adenomatous, 25% hyperplastic and 15% inflammatory. Adenomatous polyps were larger than the other types (chi 2 = 13.24, P less than 0.01), and were more frequent in the left colon than inflammatory polyps (chi 2 = 4.67, P less than 0.05). The annual incidence of colorectal polyps and the percentage of colonoscopies that revealed polyps were highest for Jews of European/American origin (5.3/10,000, 26%) compared with Jews of Israeli and Asian/African origin and Arabs (2/10,000, 6%; 1.3/10,000, 12%; and 1/10,000, 9%, respectively). These data confirm findings of other investigators showing a higher incidence of colorectal polyps in European/American Jews than in other ethnic Israeli groups.

Adolescent↗

Histopathologic and flow cytometric analysis of adenomatous colonic polyps.

We evaluated the histopathology, DNA content, and proliferative activity of colonic polyps independently. Paraffin-embedded specimens were used as source material. In each case, additional sections were cut at 3 microns and stained with hematoxylin-eosin and trichrome for histopathologic analysis. For DNA analysis and measurement of proliferative activity, the polyp parts were dissected and the nonpolypoid tissue was discarded. The study was limited to those specimens that were received in our department in the years 1972 and 1977. Of the 104 polyps that were submitted for flow cytometric analysis, 36 could not be analyzed owing to excessive debris or insufficient nuclei. DNA aneuploidy was identified in 32% of the cases, with a higher value noted in larger polyps and in severely dysplastic polyps, but these values were not statistically significant. Multiple adenomas from the same patient often showed different DNA histograms. When analyzed according to the percentage of cells in S phase, no significant difference was found in proliferative activity of polyps according to DNA content or size of the polyps. These results suggest that the diagnostic significance of aneuploidy and proliferative activity in polyps must be interpreted with caution.

Adenoma↗

Polypectomy or colectomy? Management of 106 consecutively encountered colorectal polyps.

Although malignant sessile colorectal polyps usually require colectomy for proper treatment, the majority of malignant pedunculated polyps can be removed colonoscopically. A polyp is considered malignant if the proliferating cells have penetrated the muscularis mucosa. Total excisional biopsy is necessary to properly assess an adenoma microscopically. Forceps biopsy is inadequate. Virtually all malignant pedunculated polyps can be removed colonoscopically, provided one can reach the lesion, and provided one is experienced with snare electro-surgical techniques. Certain sessile polyps can also be removed colonoscopically, if the lesion is soft and nonulcerated, and if one is familiar with piecemeal polypectomy technique developed by Shinya. If the adenoma is malignant, special attention microscopically must be given to the margin of transection, to the specimen's lymphatics, and to the degree of differentiation of the malignancy. If the margin transection and lymphatics are free of tumor cells, if the malignancy is well differentiated, and if follow-up endoscopic exam reveals no residual or recurrence at the polypectomy site (i.e., Morson criteria), the malignant polyp can be considered cured by colonscopic polypectomy alone. The author's experience with 106 consecutively encountered malignant colorectal polyps over a 10 year period is reviewed. Sixty two lesions were removed by colonscopic polypectomy alone. All patients in this group have done well, except for one patient who had tumor involvement at the margin of polyp transection, who was considered inoperable because of severe medical problems, and who died from hepatic metatases 5 months later. Forty four patients underwent colectomy; 26 of these colectomies were preceded by colonoscopic polypectomy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Colonoscopic polypectomy as a tool for management of colonic polyps and detection of new lesions.

Over the past 14 years 1,000 polyps were removed via colonscope and histologically examined. There were 869 neoplastic polyps including 125 carcinomas. Non-neoplastic polyps included 32 inflammatory polyps, 32 metaplastic polyps, 27 juvenile polyps and 17 Peutz-Jeghers type polyps. Ninety-eight focal carcinomas were adequately treated by polypectomy only, whereas 9 out of 26 invasive carcinoma required further operations with one residual carcinoma in the pararectal tissue and colonic wall respectively. The criteria requiring additional surgery in invasive carcinoma are 1) lymphatic permeation of the submucosa, 2) poorly differentiated carcinoma or 3) massive invasion close to the cut end. Not only polypoid adenomas but also flat adenomas were found to exist and seem to play an important role in the adenoma-carcinoma sequence. It became clear that colonscopic polypectomy was a useful tool for the management of colonic polyps.

Adenoma↗

Adenomas, metaplastic polyps and other lesions of the large bowel: an autopsy survey.

Out of 1,014 large intestines examined, adenomatous polyps were encountered in 170 (16.8%) and metaplastic polyps in 67 (6.6%). Both types of polyps were more prevalent among the Chinese than the Malays and Indians. The prevalence rates corresponded to the relative risks for large bowel cancer for the respective ethnic groups. This suggests that causative factors such as dietary influence which are common to adenomatous polyps and cancer of the large bowel are operating at different levels among the different ethnic groups in Singapore. There are however, several factors between adenomatous polyp and colorectal cancer which are not congruent suggesting that the relationship between these two lesions though close is not a simple or direct one. On the other hand, the present study has shown several similarities between the epidemiological characteristics of metaplastic polyps and cancer of the large bowel. It is speculated that the causative factor(s) for metaplastic polyps may occur in association with carcinogen of the large bowel, but has an independent action. Consequently, while the metaplastic polyp may not itself be regarded as a premalignant lesion, the possibility that it may be a marker for increased risk for colon cancer is not excluded. Ulcerative colitis is rare in Singapore, and is not considered an important lesion in the pathogenesis of large bowel cancer in this country.

Adenoma↗

Management of nonfamilial adenomatous polyps and colon cancers.

There is evidence that patients with adenocarcinoma of the colon and synchronous adenomatous polyps are at an increased risk for developing metachronous colon cancer. A retrospective study was made of all patients with colon cancer at our institution and the associated Veterans Administration Hospital between 1974 and 1983 to help assess the need for more extensive colon resection in patients with colon cancer and synchronous adenomatous polyps. At our hospitals 470 new cases of colon cancer were identified. Nine percent (44/470) had colon cancer and concurrent adenomatous polyps. Seven (16%) of these 44 patients developed metachronous colon cancer, as compared with four of 426 patients without polyps at the initial surgery (p less than 0.001). Four patients without polyps at the initial surgery developed polyps at a later date; three of the four patients developed metachronous colon cancer. We believe that more extensive colon resection, such as total colectomy and ileoproctostomy, may play a role in preventing the occurrence of metachronous colon cancer in patients with colon cancer and synchronous adenomatous polyps. In addition, if adenomatous polyps develop after colon surgery, close endoscopic follow-up is required.

Adenocarcinoma↗

Nasal polyps: a comparative study of morphologic and etiopathogenetic aspects.

16 nasal polyps belonging to 10 male subjects aged between 40 and 70, have been removed during the same number of ethmoidectomies; the polyps have been sectioned and specimens of mucosa corresponding to the pedicle and to the different parts of the body have been collected. During the operation parts of the mucosa of the inferior turbinates were removed. All the specimens have been prepared and observed at the scanning electron microscope. The epithelium of the inferior turbinates, of the small polyps and of the apical part of all polyps were almost normal. Marked alterations of the epithelial layer have been observed in bigger polyps. Surface characteristics of nasal polyps seem to be influenced by their relationship with neighbouring structures and by their position in the nasal cavity, but mostly by their size. On the basis of these findings the authors discuss the most recent etiopathogenetic theories of nasal polyps. They finally describe some peculiar findings concerning the mucosal layer of the polyps and of the inferior turbinates of three confirmed allergic subjects and discuss their possible clinical implications.

Adult↗

Juvenile polyps of the colon and rectum.

Two hundred and fifty-eight patients with juvenile polyps were reviewed. Ten patients less than 20 years of age were found to have adenomas. The points to be presented can, therefore, be emphasized. Juvenile polyps are a distinct pathologic entity and can occur at any age and in either sex. Adenomas do exist in pediatric patients. We should not assume that every polyp in patients less than 20 years of age is automatically a juvenile polyp and, therefore, benign. Barium enema is recommended for any child or adolescent in whom one or more polyps are found. In multiple polyposis, the finding that one polyp is of the juvenile type does not necessarily rule out the presence of adenoma. Any patient with a solitary adenoma who has multiple polyps, whether adenoma or juvenile polyps, should be observed at appropriate intervals by sigmoidoscopic, roentgenographic and, possibly, colonoscopic examination. Finally, we hope that this study will inspire others to investigate further this interesting pathologic condition.

Adenoma↗

[Surgical treatment of malignant polyps of the large intestine].

The report deals with the results of surgery in 1247 cases of colonic polyps. Malignant polyps were observed in 101 cases (8.1%). Eighty percent of polyps were up to 10 mm in size. Seventy five percent of malignant polyps were more than 10 mm in diameter. 94.4% of malignant polyps were in the rectum and sigmoid colon. Electro excision of malignant polyps via fibrocolonscope or rectoscope has been used on a large scale in recent years. Within five years after operation, newly-developed tumors were detected on the same sites in 11 cases (11.8%) (benign tumors--5, malignant polyps--4, carcinoma of large bowel--2). Newly-developed tumors were found at other sites in 26 patients (benign tumors--20, malignant polyps--5 and large bowel cancer--1).

Adult↗

[Polyps of the large intestine in children].

Polyps in the large intestine is a frequent disease in children. It is more often observed in boys than in girls aged 4 to 9. In most cases solitary polyps are observed (in 73,35%). Two-three polyps are met in 21,62% of cases. Polyposis is a rare disease--0,91%. The main symptom of polyps in children is hemorrhage from the anal orifice. The method of treatment is dependent on the amount, size, height of the situs and spread of the polyps. Dissection of polyps through the rectal speculum is used more frequently, rectoromanoscope is used in rarer cases (electroexcision and coagulation). Resection of the large intestine or colotomy and ablation of polyps can be successfully used in polyposis and high situs of polyps.

Adolescent↗

Biopsy study of polyps in the duodenal bulb.

To clarify the clinical and histological features of polyps in the duodenal bulb (DB), we studied, clinicopathologically, a total of 263 patients (179 male, 84 female) with polyps in the DB. The patients were 13-86 yr of age (average age, 57.1 yr). On endoscopy, a semipedunculated or pedunculated polyp with a relatively large size was seen in 33 patients, and small polyps, either single or multiple, were incidentally discovered in 230 patients. Histological examination of the biopsied specimens from polyps revealed gastric tissue in 182 cases (69.2%), cyst formation in 51 (19.4%), and other miscellaneous lesions (tubular adenoma, Brunner's gland hyperplasia, etc.) in 30 (11.4%). With regard to the gastric tissue, a "full-thickness" or "incomplete" body-type mucosa was identified in 27 cases of polyps, and hyperplastic surface epithelium was recognized in 155. Forty cases of hyperplastic surface epithelium-type polyps were subclassified as "pyloric"-type mucosa, because pyloric gland-like components seen under the surface epithelium were identical to those of the gastric antrum. It was reconfirmed that small polyps with little or no clinical significance could be produced by various histological features.

Adolescent↗

Nasal polyps update. Histopathology.

Sinonasal polyps are benign mucosal swellings that occur in four different histological patterns. The most common type is the edematous, eosinophilic (so-called "allergic") nasal polyp, which constitutes 85-90% of nasal polyps. The edematous polyp is morphologically characterized by edema, goblet cell hyperplasia of the epithelium, thickening of the basement membrane, and of numerous leukocytes, predominantly eosinophils. The second histological type is a fibroinflammatory polyp characterized by chronic inflammation and metaplastic changes of the overlying epithelium. Another rare variant presents with pronounced hyperplasia of seromucinous glands, but otherwise shows many similarities with the edematous type of polyp. The fourth type is very rare and is a polyp with atypical stroma. This latter polyp calls for awareness and careful histological examination to avoid misdiagnosis of a neoplasm.

Humans↗

Growth rate of colon polyps and cancer.

Malignancy potential of colorectal polyps increases with size. The growth rate and destiny of each polyp is virtually unknown. It was recently shown that polyps smaller than 10 mm left in situ may partly regress or partly increase in size, whereas one quarter of polyps are unchanged after 3 years. Polyps smaller than 5 mm show a mean increase in size, whereas polyps measuring 5 to 9 mm show a mean decrease in size. Methodologic problems with the measurement of polyps and cancer are discussed. More studies of polyp growth related to risk factors are warranted.

Colonic Neoplasms↗