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Biomedical subjects

J T Guy

Publications and source records attributed to J T Guy.

At least 19 recordsLinked to original sources
PubMed1996

Photodynamic therapy for esophageal malignancy: a prospective twelve-year study.

BACKGROUND: We wanted to determine factors affecting survival rates of benefits to, and complications in patients with esophageal cancer treated with photodynamic therapy. METHODS: From 1982 to January 1994, we used photodynamic therapy to treat 77 patients with esophageal carcinoma and evaluated survival to July 1994. All patients had failed, refused, or were ineligible for surgical intervention, ionizing radiation therapy, or chemotherapy. RESULTS: The only significant variable affecting survival was clinical stage. Median survival after photodynamic therapy was as follows: all patients, 6.3 months (mean survival, 9.2 months); stage I, not reached; stage II, 12 months; stage III, 6.2 months; and stage IV, 3.5 months. For stages III and IV, a Karnofsky performance status of 70 or higher had a significant effect. For stage III, the median survival was 6.3 months when the Karnofsky performance status was equal to or greater than 70 and 3.5 months when it was less than 70. For stage IV, the median survival was 5.5 months when the Karnofsky performance status was equal to or greater than 70 and 2.5 months when it was lower than 70. Seven stage I patients with no treatment prior to photodynamic therapy had an estimated 5-year survival rate of 62%. Three patients with stage I invasive adenocarcinoma and Barrett's mucosa diagnosed when they underwent endoscopy for dysphagia were alive with no evidence of disease 17, 44, and 59 months after photodynamic therapy. CONCLUSIONS: Photodynamic therapy for esophageal carcinoma caused minimal complications and no procedure-related deaths. Photodynamic therapy can be considered an alternative treatment for patients with Barrett's esophagus with severe dysplasia or patients with stage I carcinoma who are under consideration for operation but are high surgical risks. The length of palliation for patients having "noncurative" treatment was equal to or better than that reported historically for most other treatment regimens.

Adenocarcinoma↗
PubMed1995

Phase II study of 5-fluorouracil and folinic acid in the treatment of patients with advanced gastric cancer. A Southwest Oncology Group study.

BACKGROUND: The biochemical modulation of 5-fluorouracil (5-FU) by the reduced folate folinic acid (FA) in the treatment of patients with advanced gastric cancer was examined. METHODS: The Southwest Oncology Group performed parallel randomized Phase II trials of two schedules of 5-FU and FA in 80 patients with advanced gastric cancer. Of 76 analyzable patients, 36 were randomized to receive bolus FA (200 mg/m2, days 1-4) along with continuous infusion 5-FU (1000 mg/m2, days 1-4) and 40 were randomized to receive bolus FA (200 mg/m2, days 1-5) before the bolus 5-FU (375 mg/m2, days 1-5). RESULTS: There were three (8%) partial responses (95% confidence interval [CI] 2%-22%) on the continuous infusion arm. The bolus arm had two (5%) complete responses and six (15%) partial responses for an overall response rate of 20% (95% CI 9%-36%). The median duration of response was 4.6 months for the infusion patients and 16.6 months for the bolus patients. Survival was poor, with median survival of 5 months on both regimens. Gastrointestinal toxicity was substantial, with Grade 3 mucositis observed in 36% of patients on the continuous infusion regimen versus only 10% of patients on the bolus regimen. Grade 3 or higher hematologic toxicity occurred more often in the bolus arm than in the continuous infusion arm (28% vs. 14%, respectively). Two toxic deaths occurred, one related to sepsis the other secondary to coronary insufficiency. CONCLUSIONS: Biochemical modulation of 5-FU by FA using the dose and schedules tested has only modest activity in the treatment of advanced gastric cancer.

Adenocarcinoma↗
PubMed1995

Decline of posttreatment tumor marker levels after therapy of nonsmall cell lung cancer. A useful outcome predictor.

BACKGROUND: The assessment of treatment efficacy in nonsmall cell lung cancer (NSCLC) is limited by the lack of a clear association between clinical response and survival. The prognostic usefulness of treatment-induced tumor-marker declines in NSCLC has not been established. The authors investigated the prognostic significance of treatment-induced declination in tumor marker levels of carcinoembryonic antigen, CA 19-9, and CA 125 in a group of patients with NSCLC treated with a brief course of cisplatin-based chemotherapy. METHODS: Eighty-three patients with NSCLC enrolled on 2 related treatment protocols had pretreatment tumor-marker determinations. Patients were restaged 10 to 12 weeks after study entry, and clinical and marker responses were determined. RESULTS: Thirty-eight patients (46%) had elevated pretreatment tumor markers, 36 (42%) of whom were evaluable for both clinical and marker responses. Pretreatment, the latter 36 individuals had measurable or evaluable disease, and at least one elevated tumor marker (greater than twice normal); posttreatment, they had follow-up measurements of both parameters. Of the 36 patients, 8 had normalization of tumor marker levels, 13 had 50-99% marker level declination, and 15 had less than 50% or no declination. In the same group of 36 patients, there were, 1 patient with complete clinical response, 11 with partial response, 19 with stable disease, and 5 with progressive disease. Marker responses occurred with equal frequency in clinical responders and nonresponders. There was no association between clinical response and survival, but there was a strong association between marker response and survival. CONCLUSIONS: In patients with nonsmall cell lung cancer with elevated pretreatment tumor marker levels, treatment-induced marker level declination can be a surrogate indicator for survival.

Adult↗
PubMed1990

Phase II evaluation of mitoxantrone in advanced pancreatic carcinoma: a Southwest Oncology Group study.

Patient with advanced adenocarcinoma of the pancreas and no prior chemotherapy were treated on a Phase II trial of mitoxantrone. Doses were adjusted for hepatic dysfunction as defined by bilirubin. Twenty-four patients with a bilirubin less than or equal to 1.5 mg% received mitoxantrone 12 mg/m2 i.v. repeated every three weeks. Myelosuppression in the form of leukopenia was the major toxicity. There were no responses in twenty-four evaluable patients.

Adenocarcinoma↗
PubMed1989

Photodynamic therapy for esophageal tumors.

Between 1982 and 1987, 40 patients with esophageal tumors (19 adenocarcinomas, 19 squamous carcinomas, and two melanomas) in whom conventional treatments were unsuccessful were treated with photodynamic therapy (PDT) after injection with either hematoporphyrin derivative or dihematoporphyrin ether. Patients underwent endoscopy again two to three days and one month after PDT and as needed when symptoms recurred. At one month, the average minimal diameter opening of 28 assessable tumors increased from 6 to 9 mm. Of the 35 patients who could be evaluated one month after PDT, the average improvement in food intake was from a liquid to a soft diet. Average survival time (from time of first treatment) was 7.7 months (n = 17) for adenocarcinoma, 5.8 months (n = 12) for squamous cell carcinoma, and 25 months (n = 2) for melanoma. Two patients with stage I adenocarcinoma were alive with no evidence of disease at 11 and 23 months. One patient with stage I squamous cell cancer died 18 months after PDT, with recurrence of tumor above the treated area noted eight months after treatment. One patient with stage I melanoma died of a synchronous colon cancer 31 months after PDT, with no evidence of residual melanoma.

Adenocarcinoma↗
PubMed1989

Photodynamic therapy for cutaneous and subcutaneous malignant neoplasms.

Twenty-seven patients with cutaneous and subcutaneous malignant neoplasms were treated with photodynamic therapy. Therapy was administered to 248 areas during a total of 72 separate treatment sessions after patients received a total of 45 injections of sensitizer. Seven patients had basal cell carcinoma, three had squamous cell carcinoma, three had malignant melanoma, one had liposarcoma, and 12 had breast cancers. One patient had Bowen's disease. Treatment was given either by surface radiation or interstitially. One month after treatment, 48 (67%) of the treatment sessions resulted in a complete response (no clinical evidence of tumor), and 19 (26%) resulted in a partial response (greater than 50% reduction in the number or size of tumors). Fifteen patients were examinable 12 months after treatment, and in this group, 31 treatment sessions were evaluated as a complete response one month after therapy, 15 (48%) of which retained this status at one year after treatment. By comparing the ability of different light-delivery instrumentation, it was concluded that the Yellow Springs radiometer (Yellow Springs Instruments, model 65A, Yellow Springs, Ohio) provided the most reliable spot power density readings. Straight-tipped fibers are nonhomogeneous and can result in overtreatment of the central area with necrosis and pain and in undertreatment of the periphery.

Humans↗
PubMed1989

Phase II study of diaziquone in untreated advanced gastric carcinoma. A Southwest Oncology Group Study.

Twenty-nine patients with a diagnosis of advanced adenocarcinoma of the stomach with gross unresectable or measurable residual disease and no prior therapy were entered into a study utilizing diaziquone (AZQ) in an intermittent 3-week schedule of 40 mg/m2. Of 28 eligible patients, 1 (4%) experienced a partial response, 7 (25%) had stable disease of no response, and 18 (64%) developed increasing disease. Two (7%) were unevaluable. Median survival was 3.8 months. Major toxicities were myelosuppression and gastrointestinal, 11 of which were considered to be life-threatening. AZQ used as a single intermittent agent appears to have no significant activity to warrant use in untreated advanced gastric carcinoma. However, recognizing the short plasma half-life of AZQ, significant responses by other schedules of administration are not precluded.

Adenocarcinoma↗
PubMed1987

Phase II evaluation of bisantrene hydrochloride in refractory malignant melanoma. A Southwest Oncology Group Study.

Patients with a pathologically proven diagnosis of malignant melanoma were entered into a phase II trial of bisantrene. Eligibility criteria included: measurable, metastatic disease; performance status 0-2 SWOG; and adriamycin total cumulative dose of less than 400 mg/m2. The initial bisantrene dosing schedule was 260 mg/m2 every three weeks for good risk patients. Due to the absence of an objective response and the lack of severe toxicity in the first 25 bisantrene treated patients, the starting dose was increased to 300 mg/m2 for good risk patients. Fifty-one patients received a median of two bisantrene courses (range 1-11 courses). Leukopenia was the major toxicity. Fifteen (68%) of the 22 good risk, intermediate dose patients (260 mg/m2), and 8 (80%) of the 10 good risk, high dose patients (300 mg/m2) evaluable for toxicity experienced mild-severe leukopenia. None of the 51 patients experienced a complete or partial response to bisantrene. Median survival was 3.3 months. We conclude that bisantrene is ineffective in the treatment of metastatic melanoma.

Adult↗
PubMed1984

Hepatic artery ligation and portal vein infusion for liver metastases from colon cancer.

Localized treatment of liver metastases from colon cancer has yielded better results than has systemic therapy. We report 19 patients with metastatic colon cancer whose bulk disease was limited to the liver, but was not amenable to surgical resection. Many of these patients had poor prognostic features: 14 had greater than 30% replacement of the liver, five had poorly differentiated tumor, and five had previously failed to respond to systemic chemotherapy. All were treated with hepatic artery ligation and portal vein infusion of chemotherapy (mitomycin C and 5-fluorouracil). Two patients (10%) died within one month postoperatively. The remaining 17 patients all improved clinically and demonstrated a marked decrease in carcinoembryonic antigen (CEA) levels. Based on follow-up physical exam, liver function tests, computed tomographic scan, and/or laparotomy, there were two complete responses, ten partial responses, four improved, and one indeterminate, for an objective response rate of 63%. Median survival of all patients was 13 months after hepatic artery ligation, and 14 months after diagnosis of liver metastases, with four patients still alive at 13+, 16+, 41+, and 61+ months after hepatic artery ligation. We believe that this form of therapy is an effective, well-tolerated alternative for patients with unresectable liver metastases.

Aged↗
PubMed1983

Hematoporphyrin-derivative and photoradiation therapy of malignant tumors.

Kodak projectors with #2418 red Corning filters were used as a light source to treat cutaneous and subcutaneous malignancies in five patients who previously had been given hematoporphyrin derivative (HpD). An argon dye laser system was used to treat malignancies in patients who also were given the HpD. These tumors included 11 melanomas of the eye, three carcinomas of the esophagus, one melanoma of the esophagus, four carcinomas of the lung, three basal cell skin cancers, and one retropharyngeal metastatic oral cancer. Clinical results and technical problems of this therapy are discussed.

Adenocarcinoma↗
PubMed1976

Primary hyperparathyroidism and anemia.

The frequency of anemia associated with primary hyperparathyroidism is uncertain. When anemia does occur, its mechanisms are obscure. Two patients with primary hyperparathyroidism and moderate normochromic, normocytic, reticulocytopenic anemia were studied in detail. Both had results of ferrokinetic studies that were consistent with the anemia of chronic disease; one had low serum iron concentrations and reduced normoblastic iron incorporation. Anemia in both patients resolved after parathyroidectomy. Clinical records of 100 nonuremic patients with primary hyperparathyroidism were reviewed and three other anemic patients were found. The cause of anemia in two of these individuals was bleeding in the upper gastrointestinal system, and the third had folate deficiency attributable to chronic alchoholism.

Adenoma↗