Efficacy, risk factors and complications of endoscopic polypectomy： Ten year experience at a single center

AIM： To examine the efficacy and complications of colonoscopic resection of colorectal polypoid lesions. METHODS： We retrospectively reviewed 1354 polypectomies performed on 1038 patients over a ten- year period. One hundred and sixty of these were performed for large polyps, those measuring ≥ 20 mm. Size, shape, location, histology, the technique of polypectomy used, complications, drugs assumption and associated intestinal or extra intestinal diseases were analyzed. For statistical analysis, the Pearson χ2 test, NPC test and a Binary Logistic Regression were used. RESULTS： The mean patient age was 65.9 ± 12.4 years, with 671 men and 367 women. The mean size of polyps removed was 9.45 ± 9.56 mm while the size of large polyps was 31.5 ± 10.8 mm. There were 388 pedunculated and 966 sessile polyps and the most common location was the sigmoid colon （41.3%）. The most frequent histology was tubular adenoma （55.9%） while for the large polyps was villous （92/160 -57.5%）. Coexistent malignancy was observed in 28 polyps （2.1%） and of these, 20 were large polyps. There were 17 procedural bleeding （1.3%） and one perforation. The statistical analysis showed that cancer is correlated to polyp size （P 〈 0.0001）; sessile shape （P 〈 0.0001） and bleeding are correlated to cardiac disease （P = 0.034）, tubular adenoma （P = 0.016） and polyp size.CONCLUSION： The endoscopic resection is a simple and safe procedure for removing colon rectal neoplastic lesions and should be considered the treatment of choice for large colorectal polyps. The polyp size is an important risk factor for malignancy and for bleeding.     

Comparison of the clinicopathologic features between flat and polypoid adenoma

Objective. Several reports have suggested that flat colorectal adenomas might exhibit a higher potential for malignancy compared to polypoid adenomas. Although the clinical importance of the shape of polyps is stressed, the controversy surrounding the malignant potential of flat adenomas continues. The aim of this study was to compare the clinicopathologic characteristics, including degree of dysplasia and malignancy, between flat and polypoid adenomas 5 mm in size or larger. Material and methods. A total of 3263 polyps (254 flat adenomas and 3009 polypoid adenomas), ≥5 mm in size, diagnosed in 1883 patients by colonoscopy were analyzed. Results. Flat adenomas were found in 10% of patients, which represented 7.8% of all adenomas removed. The flat adenomas were larger in diameter than the polypoid adenomas (14.8±12.6 mm versus 8.6±5.0 mm, p <0.01), had a higher rate of villous components (18.5% versus 11.4%, p <0.01), a higher rate of high-grade dysplasia (9.4% versus 4.2%, p <0.01), and a higher rate of malignancy (10.2% versus 3.6%, p <0.01) than polypoid adenomas. However, there was no difference in the rate of high-grade dysplasia or carcinoma between flat and polypoid adenomas of equal size. It was shown by multivariate analysis that rectosigmoid location, larger size, and presence of a villous component were associated with a higher rate of malignancy, but not with flat morphology. Conclusions. Flat adenomas, which were of a relatively large size in this study, were not associated with a higher risk for high-grade dysplasia and carcinoma compared with polypoid adenomas.     

Long-term follow up of gallbladder polyps

Background and Aim:  The management of gallbladder polyps (GBP) is directly linked to the early diagnosis of gallbladder cancer (GBC). This study aimed to evaluate the malignant risk of GBP.
Methods:  In total, 1558 patients diagnosed with GBP were followed. Neoplastic polyps were defined as GBC and its premalignant lesions. The risk for malignancy was estimated with the cumulative detection rate of neoplastic polyps.
Results:  Thirty-three cases (2.1%) were diagnosed with neoplastic polyps. The cumulative detection rates of neoplastic polyps were 1.7% at 1 year, 2.8% at 5 years, and 4% at 8 years after diagnosis. The size of GBP and the presence of gallstones were risk factors for neoplastic polyps. Polyps ≥ 10 mm had a 24.2 times greater risk of malignancy than polyps < 10 mm. However, 15 of 33 neoplastic polyps (45.5%) were < 10 mm at the time of diagnosis of GBP. During follow up in 36 (3.5%) of 1027 cases, an increase in size was detected; of these, nine (25%) had neoplastic polyps.
Conclusion:  Even small polyps have a risk of malignancy, and careful long-term follow up of GBP will help detect and treat early GBC.     

Poor correlation between clinical impression, the small colonic polyp and their neoplastic risk

BACKGROUND AND OBJECTIVES: Significance of the small colonic polyp is unclear and its removal is frequently determined by the proceduralist's clinical impression. Our aims were to determine if clinical discernment is accurate, and the likelihood that lesions < 10 mm are histologically advanced. METHOD: We prospectively collected 1988 lesions from 854 subjects (2215 consecutive colonoscopies). Lesion size, location, patient age, sex and the colonoscopist's clinical impression was recorded. RESULTS: Clinical assessment for neoplasia had a sensitivity of 87.4%, specificity of 65.0%, positive predictive value of 76.0% and negative predictive value of 80.2%, resulting in an accuracy of 73.4%. Factors predictive of correct clinical impression were polyp size, location in the rectum and being pedunculated, but not the patient's age, sex or the endoscopist's experience. Of the 1434 lesions < or = 5 mm in size, 44.5% were neoplastic and 3.5% were histologically advanced. Of the 266 lesions 6-9 mm, 79.3% were neoplastic, 19.9% were histologically advanced, five demonstrated high-grade dysplasia and three were malignant. Only two patients with an adenocarcinoma or high-grade dysplasia in a polyp <10 mm had a lesion > or =10 mm elsewhere in the colon. Of the 288 lesions > or =10 mm in size, 92.7% were neoplastic, 29.5% had a villous component, 6.9% demonstrated high-grade dysplasia and 29.2% were malignant. Factors predictive of neoplasia were patient age, polyp size and sessile nature of the lesion. CONCLUSION: Polyps < 10 mm had a significant risk of neoplasia and advanced histology and, in general, clinical impression correlated poorly with neoplasia. Removal of all lesions proximal to the rectum, regardless of size, should therefore be considered.     

Flat colorectal neoplasms and the impact of the revised Vienna Classification on their reporting: a case-control study in UK and Japanese patients

OBJECTIVE: The prevalence and interpretation of flat colorectal neoplasms in the East or West remain highly variable. Several factors may contribute to this variability including differences in reporting techniques between Japanese and Western histopathologists when lesions are classified. The aims of this study were (i) to determine the frequency and characteristics of flat colorectal neoplasms in British and Japanese patients, (ii) to examine whether histopathological discrepancies exist between Western and Japanese-trained pathologists applying conventional classification methods and (iii) to determine the impact of the revised Vienna Classification on any differences observed. MATERIAL AND METHODS: One hundred and forty-four patients in the United Kingdom with neoplastic lesions prospectively identified by a colonoscopist, fully-trained in Japan, were age and gender-matched with 144 Japanese patients with neoplastic lesions detected by the same colonoscopist. Two British and two Japanese pathologists were independently asked to assess all neoplasms using both conventional and revised Vienna Classification methods. RESULTS: No significant difference in the frequency of flat neoplasms was found between British and Japanese patients; however, flat neoplasia from Japanese patients tended to contain more advanced pathologies. Discrepancies in histological diagnoses were observed between pathologists but which were reduced with the revised Vienna Classification. Japanese pathologists tended to diagnose higher grades of dysplasia for the same lesion compared to their British counterparts. CONCLUSIONS: The frequency of flat neoplasms in British and Japanese patients is similar. However, Japanese lesions, especially flat (IIb) and slightly depressed (IIc) neoplasms tend to be more biologically aggressive. The revised Vienna Classification achieves greater consensus.     

Evaluation of non-ampullary duodenal polyps: Comparison of non-neoplastic and neoplastic lesions

AIM: To evaluate duodenal polyps, divided into nonneoplastic and neoplastic lesions. In addition, the clinical characteristics of duodenal hyperplastic polyps are determined. METHODS: We analyzed medical records of 50 114 consecutive patients submitted to for first diagnostic esophago-gastroduodenoscopy between January 2004 and December 2009. We excluded lesions on the ampulla of Vater and submucosal tumors. We studied 510 cases that were diagnosed endoscopically with duodenal polyps and enrolled a total of 221 cases that had undergone tissue biopsy. We analyzed the differences between non-neoplastic and neoplastic lesions, and determined the clinical features of duodenal hyperplastic polyps. RESULTS: Non-neoplastic lesions were found in 196 patients and neoplastic lesions in 25 patients. On uni-variate analysis, there were significant differences in shape, location, and size. Polyps more than 10 mm in diameter or polyps in the second portion had independent risk factors for being neoplastic lesions, as identified by multivariate analysis. In 23 cases of hyperplastic polyps (79.3%), they were accompanied by gastroduodenal pathology, which was possibly associated with Helicobacter pylori . CONCLUSION: Polyps of more than 10 mm or polyps in the second portion of the duodenum should be evaluated by histological examination.     

Endoscopic mucosal resection for colorectal neoplastic lesions

PURPOSE: Endoscopic mucosal resection, which is a new option for endoscopic polypectomy of colorectal polyps without stalks, was evaluated on its usefulness in polypectomy. METHODS: Three hundred thirty-seven lesions, which were removed by endoscopic mucosal resection between January 1990 and January 1993, were studied. The endoscopic configuration of neoplastic lesions were classified into four types: flat, sessile, large sessile with distinct lobulations, and semipedunculated. RESULTS: The 337 lesions included 243 adenomas, 30 mucosal cancers, 13 submucosal cancers, 3 carcinoids, 43 hyperplastic polyps, and 5 inflammatory polyps. Of the 286 neoplastic lesions, excluding 3 carcinoids, 137 were flat, 81 were sessile, 18 were large sessile, and 50 were semipedunculated. The 137 flat lesions consisted of 125 adenomas, 10 mucosal cancers, and 2 submucosal cancers. The rate of complete removal was related to their size and configuration and was 87 percent in flat neoplastic lesions. Lesion diameters of greater than 20 mm and the large sessile-type configurations were factors that were associated with incomplete removal. Two (0.7 percent) cases were complicated by perforations, and one (0.4 percent) case was complicated by bleeding. CONCLUSION: Endoscopic mucosal resection is an useful option for complete removal of colorectal nonpolypoid adenomas and cancers.     

Follicular neoplasms of the thyroid: what to recommend.

Follicular neoplasms of the thyroid are usually diagnosed following fine-needle aspiration (FNA) biopsy of a dominant thyroid nodule. An FNA diagnosis of a follicular neoplasm represents a heterogeneous group of lesions including benign follicular hyperplasia, follicular adenomas, follicular carcinomas, and the follicular variant of papillary carcinoma. Hürthle cell neoplasms are also often included in this group. Because the criteria for malignancy in both follicular and Hürthle cell neoplasms requires vascular or capsular invasion seen on permanent histology, the majority of these patients undergo surgical resection. Intraoperative frozen section analysis of follicular neoplasms rarely renders informative information. Approximately 20% of these lesions prove to be malignant and for lesions greater than 1.0 cm in size, the majority of surgeons and endocrinologists recommend a total thyroidectomy. Postoperative treatment generally includes therapeutic doses of 131I for follicular carcinomas.     

Diagnostic accuracy of endoscopic ultrasound-guided fine needle aspiration for suspected pancreatic malignancy in relation to the size of lesions

Background and Aim: Endoscopic ultrasound‐guided fine needle aspiration (EUS‐FNA) is an accurate method for cytological confirmation of pancreatic malignancy, but it has been unknown whether its diagnostic accuracy for pancreatic lesions was affected by their size, location, or size of needles. Our aim was to investigate the accuracy of EUS‐FNA for suspected pancreatic malignancy in relation to these factors, especially to the size of lesions. Methods: In a tertiary referral center, EUS‐FNAs for 120 suspected pancreatic malignancies in 115 patients based on other imaging studies were evaluated retrospectively. Results: Overall accuracy of EUS‐FNA was 96% (115/120), with sensitivity of 95% (76/80), specificity of 98% (39/40), positive predictive value of 99% (76/77), and negative predictive value of 91% (39/43). Accuracies for lesions less than 10 mm, 11–20 mm, 21–30 mm, and more than 31 mm were 96%, 95%, 96%, and 100%, respectively; those for lesions in the head, the body, and the tail of the pancreas were 96%, 95%, and 95%, respectively. Accuracies for 22‐gauge and 25‐gauge needle were 93% and 98%, respectively. Conclusion: EUS‐FNA was accurate in the evaluation of suspected pancreatic malignancy regardless of its size, location, or size of needles. It was useful also in the confirmation of small pancreatic malignancies less than 10 mm.     

Endoscopic mucosal resection for colonic non-polypoid neoplasms

BACKGROUND: Colonic neoplastic lesions can be classified morphologically into polypoid and non-polypoid types. Non-polypoid lesions have a higher malignant potential than polypoid lesions. Removing these lesions and obtaining integral specimen for histopathology evaluation during colonoscopy examination is an important task. Endoscopic mucosal resection (EMR) is an alternative to surgery for removing of non-polypoid lesions of the GI tract. This study assessed the safety, efficacy, and clinical outcomes of EMR. PATIENTS AND METHODS: From October 2000 to October 2003 during the routine colonoscopy performed at one medical center, identified 152 non-polypoid colonic neoplasms in 149 patients (92 males, 57 females) were found. The mean patient age was 57.8 +/- 15.5 yr (range 32-80 yr). EMR was performed for lesions suspected of being neoplastic tumors via magnification colonoscopy with the indigo carmine dye spray method. The lesions were removed via EMR with pure cutting current after which hemoclips were applied to the resected wounds. RESULTS: The study identified 40 flat type lesions, 106 lateral spreading tumors, and 6 depressed lesions that were completely resected. The mean size of lesions was 19.4 +/- 10.3 mm (range 6-60 mm). Histological findings were 4 adenocarcinomas, 59 with high-grade adenoma/dysplasia, and 89 with low-grade adenoma/dysplasia. Two patients experienced bleeding immediately following EMR, while adequate hemostasis was achieved using hemoclips. Neither delayed bleeding nor perforation developed following EMR. CONCLUSION: EMR by using pure cutting current and hemoclip is a useful method for obtaining integral specimen for accurate pathologic assessment. This method provides a safe and minimally invasive technique managing of colonic non-polypoid lesions.     

Clinicopathologic features of the flat adenoma

One hundred twenty-eight small flat adenomas (SFAs) were collected from 101 patients, and the clinicopathologic features were investigated. There were 91 adenomas with mild atypia, 20 with moderate atypia, and 17 with severe atypia. SFAs were found more often in males than in females, with a ratio of 3.4:1, and the malignancy rate in females (31.8 percent) was higher than in males (9.3 percent). About 38 percent of the patients had a history of colorectal carcinoma, and 65 percent had a history of colorectal neoplasms. Of 37 patients whose family history was traced, 21 had cancer families. SFAs were prone to be found in patients with a history of colorectal neoplasms and a cancer family. Malignancy rate increased with increasing size. The overall malignancy rate was 13.3 percent, which was considerably higher than that of ordinary small polypoid adenomas (2.8 percent). SFAs were situated more proximally (30.9 percent) than ordinary adenomas; however, there was no relationship between site and malignancy. All the lesions showed tubular adenomas, and there was no villous feature. A central depression was noted in 20 lesions, more frequently in adenomas with higher atypia. All but one adenoma with severe atypia showed a component of lower atypia, supporting the adenoma-carcinoma sequence.     

Molecular analysis of diminutive,flat, depressed colorectal lesions: are they precursors of polypoid adenoma or early stage carcinoma?

BACKGROUND: The diminutive, flat depressed colorectal lesion is a possible precursor of early stage carcinoma. However, the significance of this lesion in colon carcinogenesis remains unclear. METHODS: Eighty-one diminutive flat lesions (<5 mm diameter) with a central depression (DPdep) were resected colonoscopically and their molecular characteristics were investigated. In parallel, 68 diminutive polyps (<5 mm diameter) with a polypoid growth pattern but no depression (DPpo) were analyzed as controls. After histopathologic diagnosis, only neoplastic tissues were stained by immunohistochemistry for p53 gene and cyclooxygenase 2 (COX-2) and the proliferation marker, Ki-67. Mutation of the K-ras gene was analyzed with the polymerase chain reaction-restriction fragment length polymorphism method by using DNA from microdissected tissue in paraffin sections. RESULTS: Seventy-nine of 81 DPdep and 35 of 68 DPpo were diagnosed as neoplastic. Mild, moderate, and severe dysplasia were found in, respectively, 56, 15, and 8 DPdep polyps, and in 34, 1, and 0 DPpo polyps. Thus, DPdep were more likely to be neoplastic and to exhibit moderate and severe dysplasia compared with DPpo (p < 0.0001). No DPdep or DPpo was positive for the p53 protein. The proportion of specimens with K-ras codon 12 mutation was 13.4% in diminutive polyps (DP), and tended to be lower in DPdep (8.6%) than in DPpo (25.0%) (p = 0.073). The median (interquartile range) of the Ki-67 index of DPdep tended to be lower than that of DPpo (respectively, 0.0 [0.0-5.9] vs. 4.5 [0.0-17.1]; p = 0.0281). COX-2 overexpression was observed in 12 of 77 (15.6%) DP and there was no significant difference between DPdep (3 of 23, 13.0%) and DPpo (9 of 54, 16.7%). CONCLUSION: Diminutive, flat, depressed lesions in this study had low rates of the genetic alterations associated with malignant progression. This indicates that either a different neoplastic mechanism is operative or that these lesions have a lower malignant potential than indicated by their histopathologic features.     

Chromoendoscopic colonoscopy for detecting preneoplastic lesions in hereditary nonpolyposis colorectal cancer syndrome.

BACKGROUND & AIMS: In hereditary nonpolyposis colorectal cancer (HNPCC) syndrome, flat and small adenomas are particularly prone to malignant transformation but might be missed by standard colonoscopy. We prospectively studied the diagnostic yield of high-resolution colonoscopy coupled with chromoendoscopy for preneoplastic and neoplastic colorectal lesions in patients with HNPCC syndrome. METHODS: Thirty-six consecutive asymptomatic patients (mean age, 42 years) belonging to HNPCC families and receiving genetic counseling were enrolled in this prospective study. Colonoscopy was performed in 2 steps. Conventional colonoscopy was performed first, followed by a second colonoscopy with chromoendoscopy with indigo carmine (.4%) dye sprayed onto the entire proximal colon. RESULTS: Conventional colonoscopy identified 25 lesions (mean size, 4 +/- 3 mm) in 13 patients. Seven lesions, detected in 5 patients, were adenomas, 3 of which were located in the proximal colon. Chromoendoscopy identified additional 45 lesions (mean size, 3 +/- 1 mm) in 20 patients; most of these lesions were flat and hyperplastic. Eleven additional adenomas were detected in the proximal colon of 8 patients, and 8 of these 11 lesions were flat. The use of chromoendoscopy significantly increased the detection rate of adenomas in the proximal colon, from 3 of 33 patients to 10 of 33 patients (P = .045). CONCLUSION: Relative to conventional colonoscopy, high-resolution colonoscopy with chromoendoscopy markedly improves the detection of adenomas in patients with HNPCC syndrome and might help to prevent colorectal carcinoma in these patients with a very high risk of colorectal cancer.     

Endoscopic ultrasonography for differential diagnosis of polypoid gall bladder lesions: analysis in surgical and follow up series

BACKGROUND: Differential diagnosis is often difficult for small (相似文献   

Incidence and recurrence rates of colorectal adenomas estimated by annually repeated colonoscopies on asymptomatic Japanese

BACKGROUND: Whereas high recurrence rates of colorectal adenomas after polypectomy are widely recognised, little is known of the natural incidence in those with no neoplastic lesions initially. It is also known that single colonoscopy has a significant miss rate. AIMS: To elucidate the incidence and recurrence rates of colorectal neoplasms from a large cohort of asymptomatic Japanese patients on the basis of annually repeated colonoscopies. METHODS: A total of 6225 subjects (4659 men and 1566 women) participating in an annual colonoscopic screening programme and completing three or more colonoscopies were analysed during the 14 year period between 1988 and 2002. Patients were divided into three groups according to the findings of the initial two colonoscopies: 4084 subjects with no neoplasm, 1818 with small adenomas <10 mm, and 323 with advanced lesions, including carcinoma in situ, severe dysplasia, or large adenomas > or =10 mm. Mean age at the second colonoscopy was 48.8 years. RESULTS: For all types of colorectal neoplasms, the incidence rate in those with no initial neoplasm was 7.2%/year whereas recurrence rates in those with small adenomas and advanced lesions were 19.3% and 22.9%/year, respectively. For advanced colorectal lesions, the incidence rate was 0.21%/year whereas recurrence rates in those with small adenomas and advanced lesions were 0.64% and 1.88%/year, respectively. Colorectal neoplasms were in general more likely to develop in males and older subjects. CONCLUSIONS: Although recurrence rates after polypectomy were elevated, the incidence rates in subjects with no neoplastic lesions initially were quite high.     

Malignant potential in flat elevations

Ninety-nine colonoscopically removed flat elevations were examined. They were divided into two groups: Group 1—flat elevations 1 to 5 mm in diameter (55 cases)- and Group 2—flat elevations 6 to 10 mm in diameter (44 cases). Group 2 had a higher percentage of adenomas (86.4 percent) than Group 1 (67.3 percent). In adenoma cases (flat adenomas), Group 2 tended to show a higher degree of dysplasia. The rates of mild and moderate dysplasia were 83.8 percent and 16.2 percent in Group 1 vs. 1.70 percent and 13.2 percent in Group 2, respectively. Group 2 contained six cases (15.8 percent) of intramucosal carcinoma (severe dysplasia), while there were no cancer cases in Group 1. Both malignancy rate and degree of dysplasia were size dependent; the larger the lesion the more severe the dysplasia. Our study also revealed that small flat elevations tend to contain higher numbers of nonneoplastic lesions than do larger lesions. Increased detection of nonneoplastic lesions seems to have contributed to an overall decline in the malignancy rate of flat elevations in recent reports.     

Colonoscopic resection of lateral spreading tumours: a prospective analysis of endoscopic mucosal resection

BACKGROUND: Lateral spreading tumours are superficial spreading neoplasms now increasingly diagnosed using chromoscopic colonoscopy. The clinicopathological features and safety of endoscopic mucosal resection for lateral spreading tumours (G-type "aggregate" and F-type "flat") has yet to be clarified in Western cohorts. METHODS: Eighty two patients underwent magnification chromoscopic colonoscopy using the Olympus CF240Z by a single endoscopist. All patients had received a previous colonoscopy where an endoscopic diagnosis of lateral spreading tumour was made. All lesions were examined initially using indigo carmine chromoscopy to delineate contour followed by crystal violet for magnification crypt pattern analysis. A 20 MHz "mini probe" ultrasound was used if T2 disease was suspected. Following endoscopic mucosal resection, patients were followed up at 3, 6, 12, and 24 months using total colonoscopy. RESULTS: Eighty two lateral spreading tumours were diagnosed in 80 patients (32% (26/82) F-type and 68% (56/82) G-type). G-type lesions were larger than F-type (G-type mean 42 (SD 14) mm v F-type 24 (6.4) mm; p<0.01). F-type lesions were more common in the right colon (F-type 77% (20/26) compared with G-type 39% (22/56); p<0.01) and more often associated with invasive disease (stage T2) (66% (10/15) v 33% (5/15); p<0.001). Fifty eight lesions underwent endoscopic mucosal resection (G-type 64% (37/58)/F-type 36% (21/58)). Local recurrent disease was detected in 17% of patients (10/58), all within six months of the index resection. Piecemeal resection and G-type morphology were significantly associated with recurrent disease (p<0.1). Overall "cure" rates for lateral spreading tumours using endoscopic mucosal resection at two years of follow-up was 96% (56/58). CONCLUSIONS: Endoscopic mucosal resection for lateral spreading tumours, staged as T1, is a safe and effective treatment despite their large size. Endoscopic mucosal resection may be an alternative to surgery in selected patients.     

Laterally spreading tumors of the colorectum: clinicopathologic features and malignant potential by macroscopic morphology

Background/aims

Laterally spreading tumors (LSTs) are being increasingly reported nowadays. The aims of this study were to analyze the clinicopathologic characteristics and to identify the risk factors of malignancy in patients with LSTs by morphological subclassification.

Patients and methods

The authors retrospectively reviewed 326 LSTs (287 patients). Patient characteristics, endoscopic findings, and histologic findings were analyzed. Endoscopic findings were subdivided into homogeneous, mixed nodular, flat elevated, and pseudo-depressed subtypes. The clinicopathological features of these subtypes were compared.

Results

Of the 287 patients treated, 173 (50.3 %) were male and overall mean patient age was 65?±?10 years (ranged 35 to 83 year). Of the 326 LSTs diagnosed, 116 (35.6 %) were homogeneous and 102 (31.3 %) were flat elevated subtype. The location was significantly different among morphological subtype. Tumors of the mixed nodular subtype were significantly larger than the tumors of the other three subtypes (p?=?0.00). Of the 326 lesions, 279 underwent endoscopic mucosal resection (granular type 88.1 % (177/201)/nongranular type 81.6 % (102/125)). Two hundred forty-nine lesions (76.4 %) were resected en bloc, and 45 lesions (13.8 %) were resected using the piecemeal technique. Piecemeal resection was significantly more common for the pseudo-depressed subtype (27.0 %, p?=?0.00). The overall malignancy rate on a lesion basis was 8.6 %. The malignancy rate increased with lesion size and was higher for the pseudo-depressed (24.3 %) and the mixed nodular subtype (14.1 %). Submucosal invasion was noted for 16 % of pseudo-depressed lesions, and this was significantly higher than the invasion rates of the other subtypes (p?=?0.06). By multivariate analysis, morphologic subtype, especially the pseudo-depressed or mixed nodular subtype and size larger than 20 mm were risk factor of malignancy.

Conclusions

The clinicopathological features of laterally spreading tumors differ with respect to macroscopic morphology, and the risk of malignant transformation is significantly higher for the mixed nodular or pseudo-depressed subtypes and lesion larger than 20 mm. Careful consideration is required when choosing a treatment modality, and lesions of the mixed nodular and pseudo-depressed subtypes should be completely removed.     

Two-Year Incidence of Colon Adenomas Developing after Tandem Colonoscopy

Objective: We attempted to determine an accurate frequency of new polyp growth in a cohort of veteran male patients who were initially cleared of polyps by tandem colonoscopy. Methods: Followup colonoscopy was performed 2 yr after tandem colonoscopy. A polyp was categorized as "new" if it was not located in a segment of the colon or rectum that had harbored a neoplastic polyp of the same histology at tandem colonoscopy, in contradistinction to lesions designated as "same-segment" polyps. Results: Fifty-eight of 90 patients who had tandem colonoscopy as a part of a previous study were available for follow-up colonoscopy for 2 yr. Ninety-one percent had a history of benign neoplastic polyps or cancer. Neoplastic polyps were documented in 52% (95% CI, 45–74%) of patients at followup, and 38% (95% CI, 26–52%) were found to have a total of 31 "new" lesions. All new lesions were tubular adenomas. The largest number of new polyps in an individual patient was four, and the largest new lesion was 20 mm in size with a flat, linear configuration. Most (25/31) new polyps were <5 mm, and the number of neoplastic polyps per patient at follow-up was less than at tandem colonoscopy. Conclusions: Approximately one-half of older, male patients with a history of neoplastic polyps will demonstrate neoplastic polyps at 2 yr. In at least one-third of patients, these appear to be new lesions. In some patients, de novo neoplastic polyps can grow to ≥1 cm within 2 yr.     

Prevalence and characteristics of pleural effusions in superior vena cava syndrome

OBJECTIVE AND BACKGROUND: The prevalence and characteristics of pleural effusions occurring in adults with the superior vena cava (SVC) syndrome are unknown. The purpose of the present study was to characterize these pleural effusions. METHODS: Charts of patients diagnosed with SVC syndrome at a tertiary care referral centre were reviewed. Radiographs were evaluated for the presence and size of pleural effusions, presence and location of masses and mediastinal width. If a pleural effusion was present, the patient's chart and a pre-existing database on pleural effusions were searched to determine whether the effusion was sampled and the results of any laboratory investigations on the fluid. RESULTS: The SVC syndrome occurred in 78 patients. Malignancy was the aetiology in 60% of the cases and bronchogenic carcinoma was the most common malignancy. An intravascular device was the aetiology in the majority of benign cases. Pleural effusion was found in 70% of patients with a malignant aetiology and 58% of those with a benign cause (P=0.345). The mean size of the effusions was larger in malignant cases (P=0.012). Of the 44 effusions 22 were sampled (17 in malignancy and five with benign processes); none was transudates, 20 (91%) were exudative (four of these were chylous) and the remaining two were reported as exudates but did not have pleural chemistries documented. CONCLUSIONS: More than half of patients with SVC syndrome have pleural effusions, regardless of the aetiology. However, the effusions are larger when associated with malignancy. The majority of these effusions are exudative and occasionally chylous. None was transudates.