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H Shinya

Publications and source records attributed to H Shinya.

15 recordsLinked to original sources
PubMed1979

Morphology, anatomic distribution and cancer potential of colonic polyps.

The concept of a polyp-cancer sequence is assuming increasing credibility as a factor in the development of colorectal cancer. Colonoscopy permits most colonic polyps to be endoscopically removed and studied pathologically. Of various polyp types encountered in the colon only neoplastic polyps are regarded as having malignant potential. Neoplastic polyps include tubular adenomas (formerly, adenomatous polyps), villous adenomas and villotubular adenomas (formerly, mixed or tuboglandular polyps). Cancerous changes must penetrate the muscularis mucosae for a polyp to be regarded as clinically malignant. The present report analyzes a series of 5,786 adenomas from over 7,000 polyp endoscopically removed. The largest number of each type of adenoma presented in the sigmoid colon, followed by the descending colon in terms of frequency. In all zones tubular adenomas were most common, villous least. Abnormal cellular change, from dysplasia to carcinoma in situ to invasive cancer was most frequently found in the sigmoid colon and, in all colon sectors, increased as the villous componency of the polyp increased. However, all categories of neoplastic polyps showed malignant changes. Polyp size, long recognized as a factor, was shown to be importantly related to malignant change, but invasive cancer was found even in polyps less than 1 cm in diameter. In addition, the incidence of malignancy rose parallel to the frequency of synchronous and metachronous polyps. A vigorous program for detection and endoscopic removal of colorectal polyps is recommended as a means of reducing the incidence of colorectal cancer.

Adenoma↗
PubMed1977

Angiodysplasia of the colon: diagnosis and treatment.

Gastrointestinal hemorrhage of obscure origin remains a difficult clinical problem, but newer methods of study, particularly endoscopy and angiography, have made inroads into this morass of diagnostic dilemmas. Vascular malformations represent entities that are relatively infrequent of occurrence and also difficult of detection. These characteristics render them particularly refractory to recognition. Once diagnosed, however, they are quite readily treated surgically, without resort to "blind" resections or multiple bowel entries. This report deals with three instances of obscure but important persistent blood loss into the gastrointestinal tract. In each instance, identification by customary diagnostic methods was unsuccessful, but was finally made through endoscopy and promptly cured through surgery. The bleeding in all 3 cases proved pathologically to have been caused by vascular malformations, which we have subsumed under the term "angiodysplasia."

Aged↗
PubMed1976

Flexible colonoscopy.

Colonoscopy with fiberoptic instruments has opened new vistas in diagnosis and treatment of colonic disease. Such endoscopy requires skill, experience, and judgment to be accomplished readily and safely but permits visual examination of the entire colon and, frequently, the terminal ileum as well. Although in experienced hands colonoscopy may have greater diagnostic accuracy than the barium enema, particularly with respect to colorectal cancer and polyps, the two are complementary modalities and with their combined use an extremely high rate of detection and confirmed diagnosis can be expected. The Beth Israel group introduced the technique of snare-cautery removal of colonic polyps via the colonoscope and has now successfully resected over 2500 such polyps without a single death. This is the largest world experience. Selected polyps can be removed endoscopically as an ambulatory procedure, reducing costs and incapacitation time. Neoplastic polyps often harbor invasive cancer and their extirpation is expected to reduce the incidence of overt colorectal cancer. Colonoscopy and endoscopic polypectomy offers the opportunity to check the rising incidence, morbidity, and mortality related to colorectal cancer.

Adenoma↗
PubMed1976

Treatment of volvulus of the colon by colonoscopy.

The flexible colonoscope has notable advantages over rigid instruments and can be offered as an alternative and (probably) preferable method for non-surgical reduction of colonic volvulus. When operative intervention is called for because of repeated bouts of sigmoid volvulus, colonoscopy offers a means of preoperative deflation of the twisted loop, allowing time to prepare the bowel and correct systemic disturbances such as electrolyte imbalance. The first successful management of a case of recurrent sigmoid volvulus using fiberoptic flexible colonoscope is presented. It is suggested that the fiberoptic colonoscope may have similar application for instances of volvulus occurring more proximal than in the sigmoid colon. Sigmoid volvulus in children even though rare might also be amenable to correction by colonoscopy.

Aged↗
PubMed1976

Colonoscopy.

Explore the source record for details and available documents.

Adult↗
PubMed1975

Endoscopic polypectomy. Therapeutic and clinicopathologic aspects.

The problem of the malignant potential of neoplastic colonic polyps is being, in large measure, resolved by newly derived techniques. Now most polyps may be removed endoscopically using the fiberoptic colonoscope. The largest world experience is at the Beth Israel Medical Center in New York, where over 2000 polyps have been endoscopically removed without a single death and with but one complication requiring operative intervention. Laparotomy is now reserved for polyps not suitable for endoscopic resection or where a question of residual cancer exists. Experience with endoscopic resection has called for: 1) re-assessment of colonic polyps in terms of their malignant potential; and 2) clarification of the indications for laparotomy and bowel resection subsequent to or instead of endoscopic removal. Among all polypoid lesions 0.5 cm or greater in size in the Beth Israel series, a variety of pathologic types was encountered. If only the neoplastic polyps were considered, the incidence of "malignant change" was 10.5% for 855 polyps analyzed. There is, however, a need to clarify terminology and to differentiate between carcinoma in situ and invasive cancer whenever possible. Superficial cancers (carcinomas in situ) do not recur or metastasize and require no treatment other than polyp removal. When "invasive" cancer is present (4.5% of neoplastic polyps) or the lesion is a "polypoid carcinoma" each case must be individually evaluted. Criteria for diagnosis, gross morphological features suggesting cancerous change, and current management of "malignant" polyps are discussed. Colonoscopy is an important component of the followup program whether malignant polyps are resected endoscopically or by the transabdominal route.

Adenoma↗
PubMed1975

CEA levels in patients with colorectal polyps.

Preoperative plasma CEA levels were measured in 93 selected patients with histologically defined colorectal adenomata removed at fibroptic colonoscopy in order to determine whether CEA levels are elevated in patients with colonic polyps, or vary with different histologic patterns. None of the patients had inflammatory bowel disease, previous history of carcinoma, or evidence of liver disease. Fifteen percent of the patients had elevated CEA levels (greater than or equal to 2.5 ng/ml; Hansen method), and two-thirds of these were between 2.5 and 4.0 ng/ml. Increased association of elevated CEA levels was noted with old age, villous adenomas (2- to 4-fold), and increased tumor size (greater than 2.3-cm diameter; 2-fold), but not with foci of dysplasia or carcinoma in situ as such. One-half (7/14) of the patients with elevated CEA levels showed the following: two patients had villous tumors with carcinoma in situ, one had a villous adenoma, two had mixed villous and tubular adenomas (with a high proportion of villous pattern), and two were subsequently shown to have carcinoma elsewhere in the colon. It is uncertain that the polyps were the source of the elevated circulating CEA levels; other factors including smoking and patient selection need to be considered. This preliminary study suggests that patients with colorectal adenomata and elevated circulating CEA may be at higher risk for the development of carcinoma. Further follow-up studies of the malignant potential of the polyp-bearing colon are essential.

Adenoma↗
PubMed1975

Comparison of colonoscopy and the contrast enema in five hundred patients with colorectal disease.

Endoscopic examination of the entire colon (colonoscopy) is an important new method of diagnosis and treatment of diseases of the colon and rectum, particularly cancer. The records of 500 patients who had one or more contrast enemas and subsequent colonoscopy were analyzed in an attempt to evaluate the competitive and complementary features of the two methods. The endoscopists had the advantage of having a radiologic report or radiographs available to them. In general, when the level of abnormality could be reached, colonoscopy had a higher degree of accuracy, particularly since observation could be combined with biopsy. This was particularly true in the case of polyps in which colonoscopy confirmed 166 radiologically described growths plus an additional 118 lesion, twenty-one of which were over 1 cm in diameter. By endoscopic excision of these polyps via the colonoscope, malignant changes can be identified, a conclusion rarely reached by radiographic means alone. With respect to cancer, exclusive of polyps, only twenty-four of thirty-two cases were diagnosed by x-ray study alone. Another nine, interpreted aa demonstrating malignancy from the radiographs, had cancer excluded when subjected to endoscopic confirmation. Colonoscopy has also proved valuable in identifying lesions of the cecum, notoriously a problem for the radiologist, and in identifying milder degrees of inflammatory change which are undetectable by radiographic means. Colonoscopy and the contrast enema are best reported as completmentary rather than competitive approaches, and by their combined use, diagnostic accuracy is greatly enhanced.

Barium Sulfate↗
PubMed1975

Definitive treatment of "malignant" polyps of the colon.

There has been an unremitting rise in incidence of colonic cancer in this country with no recent improvement in cure rate. As a result the evolution of colorectal cancer has been the focus of considerable attention with an enlarging body of evidence pointing to the common neoplastic polyp as a precursor to malignancy. "Neoplastic" polyps include "adenomatous polyps," "villous adenomas" and, lately recognized, "villo-glandular polyps." Experience with endoscopic removal of over 2,000 colonic polyps (with no mortality) has introduced two questions of prime concern to the surgeon: (1) What constitutes clinical malignancy in a polyp? AND, (2) When should laparatomy supplant or follow endoscopic removal? Eight hundred and ninety-two consecutive adenomatous (tubular), villous, villoglandular (villo-tubular) and "polypoid cancer" polyps are analyzed, 855 of which have been followed for 6 months to 4 years. Support is offered to the concept that villous and tubular growth patterns are merely variants of a similar base disturbance in cell renewal. Superficial cancer (carcinoma-in-situ) occurred in 6.6% of neoplastic polyps and represents no threat if the polyp is completely removed. Only when the cancer penetrates the muscularis mucosae should it be regarded as "invasive." The term "malignant polyp" should be reserved for this form. Invasive cancer was found in 5.0% of neoplastic polyps in this series. Only in this group need the question of further surgical intervention be raised. Major considerations influencing a decision for subsequent laparotomy are polyp size and gross morphology (i.e. sessile or pedunculated), histologic type (of the polyp and of the cancer itself), adequacy of clearance between depth of invasion and plane of polyp resection, and the patient's age and general condition. These are analyzed. Twenty-five of 46 patients with "malignant polyps" were subjected to abdominal exploration: 17 showed no residual cancer, whereas 8 (5 with recognized incomplete endoscopic removal) had tumor in the bowel wall. Of the remaining 21 patients, for whom endoscopic polypectomy alone was deemed appropriate, none have shown residual or recurrent cancer on clinical and endoscopic followup. Colonoscopy appears to be a most promising approach in terms of the goals of cancer programs, offering both prophylaxis and opportunity for treatment at a favorable stage of disease.

Adenoma↗
PubMed1975

Indications for fiberoptic colonscopy.

In certain clinical situations, fiberoptic colonoscopy has proved most useful and effective as a diagnostic and therapeutic tool. Colonscopy is indicated to remove polyps when feasible and to rule out the presence of toher polyps or tumors undetected by barium enema. Patients with cancer of the colon should have preoperative colonoscopy to rule out the presence of undetected polyps or metachronous cancer. Follow-up examinations are important to insure against residual cancer or recurrence after colonscopic removal of sessile, premalianant, or malignant polypoid lesions, and to evaluate certain patients who have increased risk of polyp or tumor formation. Colonscopy usually can explain persistent, localized abnormalities detected by barium enema (ie, "filling defects") and provide a definitive diagnosis in cases of unexplained rectal bleeding or diarrhea despite negative sigmoidoscopic and barium studies. In experienced hands, this technic is safe, confortable, and effective in avoiding laparotomy to remove clinically significant polyps and in providing definitive diagnosis in many clinical situations.

Barium Sulfate↗