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Biomedical subjects

T D Kummet

Publications and source records attributed to T D Kummet.

10 recordsLinked to original sources

Beta-Carotene, vitamin A, and lung cancer chemoprevention: results of an intermediate endpoint study.

A randomized, placebo-controlled clinical trial of beta-carotene and retinol was conducted with 755 former asbestos workers as study subjects. The targeted endpoint for the intervention study was a reduction in the incidence and prevalence of sputum atypia. The dosage of 50 mg beta-carotene/d and 25,000 IU retinol/d on alternate days resulted significant increases in serum concentrations of both agents with no clinically significant toxicity. Skin yellowing was observed in approximately 35% of patients and may have contributed adversely to protocol adherence. Baseline analysis revealed that smoking and drinking were associated with lower concentrations of serum beta-carotene, even after dietary carotene intake was adjusted for (P < 0.0001). Baseline concentrations of retinol were apparently lowered by smoking (P < 0.002) and increased by drinking (P < 0.0001). Drinking and smoking also were significantly related to lower beta-carotene concentrations after supplementation (P < 0.001). No significant reduction in sputum atypia was observed after treatment.

Adult↗

A prospective, controlled analysis of endoscopic cytotechniques for diagnosis of malignant biliary strictures.

We prospectively collected brushings and bile for cytology in 30 consecutive patients with bile duct strictures (17 malignant, 13 benign) who were assessed by endoscopic retrograde cholangiography. When appropriate, the cellular debris on stents that were removed from individuals who were managed with these devices was evaluated for malignant cells as well. Our aim was to assess the value of these endoscopic cytotechniques for making a diagnosis of obstructing cancer of the biliary tract. A cumulative total of 78 specimens were obtained. Overall, sensitivity was highest for stent (36%) and brush (33%) cytology, compared with results obtained from bile (6%). If the results for all methods are combined, 47% of patients with cancer (eight of 17) could be diagnosed by one or more cytological technique. There were no false-positive results (specificity, 100%). Our results show that brush and stent cytology are nearly equivalent for detecting cancer, but because a diagnosis is delayed until the endoprosthesis is removed (mean 3.4 months), the brush technique is preferred. Results for bile cytology are marginal. Specificity for these cytotechniques is high; therefore, a positive result by any method is sufficient evidence for cancer, and other invasive diagnostic procedures are unnecessary.

Aged↗

Acute myelofibrosis: response to recombinant human interferon alpha-2a.

Acute myelofibrosis is a rare myeloproliferative syndrome characterized by bone marrow proliferation of atypical megakaryocytes, poor response to conventional leukemic therapy, and a fulminant clinical course. Because alpha interferon exhibits potent antiproliferative effects against megakaryocyte progenitors and human fibroblast cell lines, we treated two patients with acute myelofibrosis or the related syndrome of acute myelodysplasia with myelofibrosis with recombinant human interferon alpha-2a. Patient 1 received a 12-week course of interferon alpha (1-6 x 10(6) IU/d) after failure of two cytarabine-based chemotherapy regimens. Interferon administration resulted in prompt improvement in symptoms, stabilization of leukocyte count, and a reduction in circulating blast forms. Primary treatment with interferon (1-3 x 10(6) IU/d x 4 weeks) in patient 2 produced complete hematologic recovery with restoration of marrow cellularity and reduced marrow fibrosis. Our findings suggest that interferon alpha may have significant activity in the treatment of patients with acute myelofibrosis.

Acute Disease↗

Spinal cord toxicity complicating treatment with cisplatin and etoposide.

Neurologic toxicity occurring in patients treated with cisplatin chemotherapy is limited primarily to peripheral neuropathy and ototoxicity. Lhermitte's sign, electric-like paresthesias precipitated by cervical spine flexion, has recently been described as a self-limited complication in cisplatin-treated patients. We report the development of Lhermitte's sign accompanied by cervical motor neuropathy, dorsal column myelopathy, and sensory neuropathy in a patient treated with cisplatin and etoposide for small cell lung cancer. Persistence of the neurologic deficit suggests that potentially irreversible spinal cord toxicity may complicate treatment with this chemotherapy combination.

Aged↗

Endoscopic retrograde wire-guided brush cytology for diagnosis of patients with malignant obstruction of the bile duct.

A brush was adapted for use over a guide wire to facilitate reliable acquisition of cytological specimens from tight and potentially malignant strictures encountered during ERCP. Cells collected in this manner were assessed for abnormalities indicative of cancer. We have called this technique endoscopic retrograde wire-guided brush cytology (ERWBC). Thirty-nine strictures (24 malignant, 15 benign) in 34 patients were brushed. There were no complications, and all specimens were adequate for evaluation. Sixty percent of patients with cancer were diagnosed by ERWBC. Sensitivity was highest for cholangiocarcinoma (100%), intermediate for pancreatic cancer (60%), and lowest for patients with biliary obstruction due to metastatic disease (22%). There were no false-positive results (specificity, 100%). The positive and negative predictive values were 100% and 58%, respectively, and accuracy for the test was 72%. Collection of cytological specimens using a brush with a wire guide is effective especially for diagnosis of cholangiocarcinoma. A positive result is sufficient evidence for malignancy, and other invasive diagnostic tests are unnecessary. We recommend ERWBC for brushing all strictures of unknown cause during ERCP in an effort to make a diagnosis of cancer.

Adenoma, Bile Duct↗

Phagocytic, lambda light chain, plasma cell myeloma.

A case of phagocytic, lambda light chain, plasma cell myeloma was characterized by its clinical, morphologic, cytochemical, immunologic, and cell kinetic features. A 40-year-old man presented with Coombs-negative hemolytic anemia, hepatosplenomegaly, lytic bone lesions, lambda light chain monoclonal gammopathy, and infiltration of the bone marrow by dysplastic plasma cells, 10% of which demonstrated phagocytosis of erythroid cells. Electron microscopy demonstrated myeloma cells with prominent cytoplasmic microfilaments and erythroid cells in intracytoplasmic vacuoles. The myeloma cells did not phagocytose staphylococci in vitro. Phagocytic and nonphagocytic myeloma cells were tartrate-sensitive, acid-phosphatase positive, alpha-napthyl butyrate esterase negative, and did not form E rosettes or EAox(IgG) rosettes. The tumor cells were Tdt, Ia antigen, and SIg negative. Immunofluorescent staining for cytoplasmic light chains showed a monoclonal lambda pattern in nonphagocytic myeloma cells, and a probable monoclonal lambda pattern in phagocytic myeloma cells. These findings characterize the neoplasm as a monoclonal proliferation of differentiated plasma cells with the capability of erythrophagocytosis. Erythrophagocytosis by myeloma cells may have been responsible for the hemolytic anemia. The tritiated thymidine labeling index (LI%) was high (8%), suggesting a poor prognosis, despite a dramatic initial response to chemotherapy.

Adult↗

Chemotherapy of pulmonary blastoma: a case report and review of the literature.

Pulmonary blastoma is a rare lung tumor of uncertain histogenesis. Although surgery may be curative therapy for localized lesions, recurrent tumor has been resistant to various treatment modalities. We report a case of metastatic pulmonary blastoma that had a partial remission with combination chemotherapy. Suggestions are made for the treatment of localized and metastatic pulmonary blastoma.

Adolescent↗