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Biomedical subjects

P C Shellito

Publications and source records attributed to P C Shellito.

36 records · Page 2Linked to original sources
PubMed1992

Are there patients with stage I rectal carcinoma at risk for failure after abdominoperineal resection?

The clinical courses of 64 patients undergoing abdominoperineal resection for Stage I lower rectal carcinoma (tumors confined to the muscularis propria without lymph node involvement) were reviewed to identify subsets at risk for failure. Twelve of 12 patients with tumors limited to the submucosa remained disease free without evidence of recurrence. Of the 52 patients with muscularis propria involvement, there have been eight failures with three patients having local failure only, three patients with local failure and distant metastases, and two patients with distant metastases only. The 6-year actuarial disease-free survival, local control, and freedom from distant metastases rates for patients with tumors invasive of the muscularis propria were 80%, 84%, and 88%, respectively. Patients with tumors exhibiting vascular/lymph vessel involvement were at even higher risk for failure. Although adjuvant treatment is infrequently advised for these patients, the use of radiation therapy and chemotherapy should be reconsidered for patients with Stage I lower rectal carcinoma, specifically for patients with tumors invasive of the muscularis propria with vascular/lymph vessel involvement.

Abdomen↗
PubMed1992

Adjuvant postoperative radiation therapy for rectal adenocarcinoma.

From October 1975 to August 1988, 261 patients at high risk for local recurrence after curative resection of rectal carcinoma underwent high-dose postoperative irradiation. Patients received 45 Gy by a 4-field box usually followed by a boost to 50.4 Gy or higher when small bowel could be excluded from the reduced field. Since January 1986, patients also received 5-fluorouracil (5-FU) for 3 consecutive days during the first and last week of radiotherapy. Five-year actuarial local control and disease-free survival decreased with increasing stage of disease; patients with Stage B2 and B3 disease had local control rates of 83% and 87% and disease-free survivals of 55% and 74%, respectively. In patients with Stage C1 through C3 tumors, local control rates ranged from 76% to 23%, and disease-free survivals ranged from 62% to 10%, respectively. For patients with Stage C disease, disease-free survival decreased progressively with increasing lymph node involvement, but local control was independent of the extent of lymph node involvement. For each stage of disease, local control and disease-free survival did not correlate with the dose of pelvic irradiation. Preliminary data from this study suggest a trend toward improved local control for patients with Stage B2, C1, and C2 tumors who receive 5-FU for 3 consecutive days during the first and last weeks of irradiation compared with patients who do not receive 5-FU. Current prospective randomized studies are addressing questions regarding the optimum administration of chemotherapy with pelvic irradiation for patients following resection of rectal carcinoma.

Adenocarcinoma↗
PubMed1991

Intraoperative electron beam radiation therapy for recurrent locally advanced rectal or rectosigmoid carcinoma.

A multimodality approach of moderate-dose to high-dose preoperative radiation therapy, surgical resection, and intraoperative electron beam radiation therapy (IORT) has been used for patients with locally recurrent rectal or rectosigmoid carcinoma. The 5-year actuarial local control and disease-free survival for 30 patients undergoing this treatment program were 26% and 19%, respectively. The most important factor predicting a favorable outcome was complete resection with negative pathologic resection margins. The determinant local control and disease-free survival for 13 patients undergoing complete resection were 62% and 54%, respectively, whereas for 17 patients undergoing partial resection these figures were 18% and 6%, respectively. There did not appear to be a difference in local control or survival based on the original surgical resection (abdominoperineal resection versus low anterior resection). However, the likelihood of obtaining a complete resection after preoperative radiation therapy was higher in patients who had previously undergone a low anterior resection than patients undergoing prior abdominoperineal resection. For the 30 patients undergoing external beam irradiation, resection, and IORT, the most significant toxicities were soft tissue or sacral injury and pelvic neuropathy. Efforts to further improve local control are directed toward the concurrent use of chemotherapy (5-fluorouracil with and without leucovorin) as radiation dose modifiers during external beam irradiation and the use of additional postoperative radiation therapy.

Adult↗
PubMed1991

Preoperative irradiation for tethered rectal carcinoma.

Twenty-eight patients with resectable but tethered rectal carcinomas were treated with preoperative irradiation (EBRT) and surgical resection. The 5-year actuarial disease-free survival and local control rates of these 28 patients were 66 and 76%, respectively. Two patients have developed local failure only, 2 patients concurrent local failures and distant metastases, and 4 patients distant metastases only. All local failures occurred in areas of tumor adherence to unresectable structures (sacrum, pelvic side wall). Patients with tethered rectal tumors are at risk for local failure despite preoperative irradiation and surgical resection. To improve local control in this subset of patients, an intraoperative radiation therapy (IORT) boost is given to areas of tumor adherence at resection following EBRT.

Adult↗
PubMed1991

Intraoperative electron beam radiation therapy for primary locally advanced rectal and rectosigmoid carcinoma.

To improve local control and survival in patients with primary locally advanced rectal and rectosigmoid carcinoma, intraoperative electron beam radiation therapy (IORT) has been used with a combination of moderate- to high-dose preoperative radiation therapy and surgical resection. Sixty-five patients underwent resection with the intention of using IORT if areas at high risk for local recurrence were apparent at surgery. For 20 patients undergoing complete resection with IORT, the 5-year actuarial local control and disease-free survival (DFS) was 88% and 53%, respectively. The results for 22 patients with pathologically documented residual carcinoma were less satisfactory with a 5-year actuarial local control and DFS of 60% and 32%, respectively. In this latter group, local control and DFS correlated with the extent of residual disease: patients with only microscopic disease had a 5-year actuarial local control and DFS of 69% and 47%, respectively, whereas for patients with macroscopic disease, these figures were 50% and 17%, respectively. For 18 patients undergoing complete resection without IORT or additional postoperative radiation therapy, the 5-year actuarial local control and DFS was 67% and 53%, respectively. Because local failure will occur in at least 30% of patients undergoing partial resection with or without IORT as well as patients undergoing complete resection of advanced tumors without IORT, additional postoperative radiation therapy should be considered.

Adult↗
PubMed1990

The freckle sign--an endoscopic feature of the cecum.

Mucosal spots, or "freckles," surrounding the appendiceal orifice are an endoscopic feature of the cecum. These are clusters of 1 to 2 mm round or oval slightly raised spots, each with a pale center and an erythematous border. They correlate microscopically with subepithelial and submucosal lymphoid follicles. The freckling pattern, identified in about one third of colonoscopies, was seen best with the videoendoscope and was identified more commonly in patients with systemic illness. Recognition of mucosal freckling around the appendiceal orifice helps identify the cecum and may be useful in the evaluation of cecal and appendiceal pathology.

Appendix↗
PubMed1989

Percutaneous endoscopic gastrostomy in head and neck cancer patients.

Unique problems accompany percutaneous endoscopic gastrostomy (PEG) in head and neck cancer patients. This study analyzed the experience of one surgeon (P.S.) performing PEG in 50 patients with advanced oropharyngeal cancer. The records of 54 such patients consecutively referred for PEG at the Massachusetts General Hospital were reviewed. A pull-through PEG technique was used. The procedure was successful in 50 patients (success rate, 93%). Failures were caused by esophageal stricture, respiratory distress, and hiatus hernia. The two patients with insurmountable esophageal stricture had piriform sinus tumors. Cancer in this location and pharyngoesophageal strictures were predictive of PEG failure. A single death, 21 days after endoscopy, was caused by pneumonia. The only major complications were two transient respiratory arrests. Neither patient had a tracheostomy in place, and both had unresected cancer present. Minor complications were transient gastroparesis, pneumonia, unexplained fever, and a broken traction suture. There were no wound or intraabdominal infections and no episodes of bleeding. While PEG was successful in 93% of these difficult patients, with few complications, results could be improved by tracheostomy or resection performed before PEG in patients with tumors near the airway and dilatation of troublesome esophageal strictures under endoscopic view before PEG.

Adult↗
PubMed1989

Patterns of failure following local excision and local excision and postoperative radiation therapy for invasive rectal adenocarcinoma.

The clinical course of 40 patients undergoing conservative surgical excision and 26 patients undergoing local excision and postoperative radiation therapy of rectal carcinoma was reviewed. Surgical procedures were transanal excision (55 patients), Kraske procedure (ten patients), and fulguration (one patient). The five-year actuarial survival, disease-free survival, and local control of all 66 patients were 70%, 77%, and 63%, respectively. For patients undergoing local excision alone, the prognostic features of lesion size greater than 3 cm, poorly differentiated histology, invasion into muscularis propria or deeper, moderate to marked stromal fibrosis, vascular or lymph vessel invasion, fragmented resection, and positive resection margins were associated with a local failure rate of 20% or greater. Of the 26 patients receiving postoperative radiation therapy, four patients have developed local failure. For subgroups of patients with small rectal carcinomas confined to the mucosa, local excision may be a reasonable alternative to abdominoperineal resection. For tumors with deeper invasion but limited to the bowel wall, local excision plus pelvic irradiation can be offered to preserve anorectal function.

Adenocarcinoma↗
PubMed1989

Indications for adjuvant radiotherapy in extrapelvic colonic carcinoma.

Although the value of postoperative radiotherapy has been demonstrated for subsets of patients with rectal carcinoma, the efficacy of postoperative radiation therapy for colonic carcinoma (above the peritoneal reflection) is much less clear. Recent studies examining the failure patterns of colonic carcinoma following resection indicate that local failure increases as a function of bowel mobility, disease extension through bowel wall, and lymph node involvement. Retrospective series reporting the results of postoperative irradiation suggest that postoperative radiation therapy to the tumor bed may be beneficial for patients with Stage B3, C2 and C3 disease with limited nodal involvement. Randomized prospective trials are required to further evaluate the efficacy of such adjuvant radiotherapy.

Colonic Neoplasms↗
PubMed1987

Treatment of recurrent colonic pseudo-obstruction by endoscopic placement of a fenestrated overtube. Report of a case.

The case of a 73-year-old man who developed acute colonic pseudo-obstruction (Ogilvie's syndrome) following chemotherapy for lymphoma is reported. Cecal dilatation resolved after a single colonoscopic decompression. Following his next course of chemotherapy, colonic dilatation again developed. The recurrence was treated successfully by introducing a fenestrated colonoscopic overtube transanally for continuous decompression. The literature concerning acute, colonic pseudo-obstruction is reviewed. The colonoscopic overtube is a convenient and effective treatment for recurrent colonic distention.

Acute Disease↗
PubMed1985

Tube gastrostomy. Techniques and complications.

For prolonged gastrointestinal decompression or enteral nutrition, gastrostomies are preferable to nasogastric tubes. To assess the safety of tube gastrostomy, the authors reviewed 424 gastrostomies systematically selected from a total of 3,359 done from 1975 through 1980. Feeding gastrostomies composed 22% of the total; the remaining 78% were done for decompression. Complications were rare (6.6% major, 6.6% minor) and were not influenced by patients' age. Perioperative steroid therapy promoted laparotomy wound infections. External and internal leakage of stomach contents, as well as bleeding from the gastrostomy site, were independent of the method of gastrostomy and the type of catheter used. Feeding gastrostomies were more likely to leak internally than were decompression gastrostomies. Unless the gastrostomy site was sutured to the anterior abdominal wall, there was a 7% incidence of extravasation of stomach contents into the peritoneal cavity after removal of the tube. The low complication rate justifies use of gastrostomies as an alternative to prolonged nasogastric intubation. Problems are minimized by employing the Stamm technique with a straight catheter and anterior gastropexy.

Adolescent↗
PubMed1984

Idiopathic intermittent gastroparesis and its surgical alleviation.

Five otherwise healthy young adults with a syndrome of recurrent intermittent gastric atony have been described. Symptomatic periods characterized by severe nausea, early satiety, and abdominal bloating alternated with asymptomatic intervals. During symptomatic phases upper gastrointestinal barium contrast radiographs demonstrated gastric dilatation with atony but without obstruction. At other times, the symptoms would disappear, and gastric size, motility, and emptying would appear normal. Upper gastrointestinal endoscopy confirmed gastric atony and showed no mucosal abnormalities or gastric outlet obstruction. No pathogenic factors were detected, and the gastroparesis was unassociated with any motility disorder of the esophagus, small bowel, or colon. Thus, it differed from other recognized forms of visceral pseudoobstruction. Because of failed medical treatment, four patients were treated with antrectomy, gastrojejunostomy, and truncal vagotomy to allow passive emptying of the stomach by gravity. All four surgically treated patients improved greatly. Idiopathic intermittent gastroparesis is a distinct clinical syndrome that can be successfully treated by surgical means in severe cases.

Acute Disease↗
PubMed1981

Predominant role of bile in modulation of early postresectional enteric hyperplasia.

Pancreaticobiliary secretions modulate compensatory hyperplasia after proximal small-bowel resection. To investigate the individual contributions of bile and pancreatic juice, levels of nucleic acids in ileal mucosa of the rat were examined 48 hours after performance of jejunectomy with selective exclusion of bile or pancreatic juice. Exclusion of bile alone inhibited the postresectional increase in levels of RNA and DNA. Exclusion of pancreatic juice (but provision of bile) did not inhibit a rise in ileal RNA or DNA levels after jejunectomy. Presence of bile seems to be one of the major elements in the early stages of adaptive hyperplasia of the ileum.

Animals↗
PubMedDate not supplied

Endoscopic resection of large sessile colorectal polyps.

Colonoscopic removal of large, sessile polyps is difficult, but can be successfully carried out by experienced endoscopists. "Piecemeal" resection with an electrocautery snare was performed at our institution in 108 patients with 132 such lesions. The mean size of the unresected polyps was 3.0 cm. Complications occurred in 3.0% of polypectomies (3.8% of patients), with bleeding necessitating transfusion in 2.3% of polypectomies (2.8% of patients), and microperforation (probable) in the remainder. No patient required emergency surgery due to a complication. In 65 patients (60%), colonoscopic resection and follow-up alone was carried out. Of these, adenomas recurred/persisted in 28%, most of which were successfully re-resected. Nearly half of all recurrent polyps occurred after at least one negative intervening examination. Carcinoma later appeared in 17% of the recurrences despite apparent initial complete resection of a previously benign polyp. Cure was ultimately achieved in 88% of endoscopically managed patients. Surgical resection was required in 27% of patients, mostly following the initial polypectomy when invasive carcinoma was found in the specimen. No residual tumor was later found in 41% of the colon specimens from these patients. Ninety-one percent of cancers were favorable stage, whether discovered early or late. Follow-up colonoscopy was achieved in 77% of patients over an average of 3.7 years. Metachronous polyps were excised in 52 patients (63%) and metachronous carcinoma was diagnosed in 3 patients (3.6%). An aggressive regimen of surveillance colonoscopy is warranted in these patients to detect and manage local recurrences and to remove subsequent adenomas. Endoscopic resection of large sessile adenomas can be safe and effective.

Aged↗
PubMedDate not supplied

Does postoperative irradiation play a role in the adjuvant therapy of stage T4 colon cancer?

PURPOSE: This study analyzes the long-term outcome of patients with stage T4 colon cancer who receive postoperative irradiation. The purpose of the study is to define the potential role of this modality with current systemic therapies. PATIENTS AND METHODS: A retrospective analysis was performed of 152 patients undergoing resection of T4 colon cancer followed by moderate- to high-dose postoperative tumor bed irradiation with and without 5-fluorouracil-based chemotherapy. Of the 152 patients, 110 patients (T4N0 or T4N+) were treated adjuvantly, whereas 42 patients received irradiation for the control of gross or microscopic residual local tumor. RESULTS: For 79 adjuvantly treated patients with stage T4N0 or T4N+ cancer with one lymph node metastasis, the 10-year actuarial rates of local control and recurrence-free survival were 88% and 58%, respectively. Results were less satisfactory for patients with more extensive nodal involvement. The 10-year actuarial rates of local control and recurrence-free survival of 39 patients with T4 tumors complicated by perforation or fistulas were 81% and 53%, respectively. For 42 patients with incompletely resected tumors, the 10-year actuarial recurrence-free survival was 19%. CONCLUSIONS: In comparison with historical controls, postoperative tumor bed irradiation improves local control for some subsets of patients. In addition to standard 5-fluorouracil-based chemotherapy, adjuvant tumor bed irradiation should be considered when colon cancers invade adjoining structures, when they are complicated by perforation or fistulas, or when they are incompletely excised at the primary site.

Adult↗