Showing papers by "Scott M. Lippman published in 1987"

Retinoids as preventive and therapeutic anticancer agents (Part I).

Abstract: Retinoids, the synthetic and natural analogs of vitamin A, frequently block the phenotypic expression of cancer in vitro; they also inhibit growth and induce differentiation in many animal and human malignant cell types. Only recently has it become possible to propose a unifying mechanism of retinoid action, which involves the protein kinase-C cascade system. This system may mediate retinoids' many diverse actions, including their effects on enzyme synthesis, membrane properties, growth factors, binding proteins, genomic and postgenomic expression, the extracellular matrix, and immunologic responses. Ongoing in vitro studies of retinoid structure-activity relationships, effects on oncogene expression, reversal of drug-resistance, and, especially, the protein kinase-C cascade system should help clarify the precise mechanism of their anticancer action. Many in vitro and in vivo assay systems are available for testing the 2000 + synthetic retinoids. These assays indicate specific drug sensitivities, which may help focus future clinical trials. In human cancer prevention, retinoids have been most effective for skin diseases, including actinic keratosis, keratoacanthoma, and basal cell carcinoma; however, nondermatologic premalignancies, such as oral leukoplakia, bronchial metaplasia, laryngeal papillomatosis, cervical dysplasia, myelodysplastic syndromes, and the urinary bladder, also respond to retinoid therapy. Significant therapeutic advances are also occurring with this class of drugs in refractory malignancies, including advanced cutaneous squamous and basal cell cancer, mycosis fungoides, and acute promyelocytic leukemia. Newer third-generation retinoids, such as the highly potent retinoidal benzoic acid derivatives, are demonstrating therapeutic indexes far higher than earlier-generation retinoids. Current in vitro testing is also demonstrating that retinoids have synergistic activity in combination with other agents (eg, biologic modifiers, hormones, and DNA synthesis inhibitors) and treatment modalities (eg, irradiation). Notwithstanding the progress already made with retinoids in human cancer, many in vitro questions remain, and clinical work is just beginning.

Treatment of Advanced Squamous Cell Carcinoma of the Skin with Isotretinoin

Abstract: Study Objective:To determine the efficacy of oral isotretinoin in refractory advanced squamous cell carcinoma of the skin. Design:Case series trial. Setting:Tertiary care center at a unive...

Radiation therapy salvage of Hodgkin's disease following chemotherapy failure.

Abstract: Between 1972 and 1984, 17 patients with advanced Hodgkin's disease failing intensive combination chemotherapy in previously unirradiated nodal and/or pulmonary sites were treated with salvage radiotherapy. Treatment consisted of comprehensive wide field radiotherapy to all known areas of disease. Doses administered to these fields ranged from 1,700 to 5,000 rad, with only three patients (18%) receiving less than 3,000 rad to any field. With a median follow-up of over 4 years, 88% achieved a complete response, with median actuarial disease-free survival (DFS) of 19 months (range, 4 to 61+). Actuarial median survival was 64 months, with a range of 4 to 134+ months. Nine patients (53%) are currently alive with three (18%) in continuous complete remission (CR) for 24, 30, and 61 months. In addition, four patients relapsing after salvage radiotherapy are now in CR following additional therapy. Patients younger than 35 years of age had a significantly increased overall survival when compared with older patients...

Lethal midline granuloma with a novel T‐Cell phenotype as found in peripheral T‐Cell lymphoma

Abstract: Lethal midline granuloma (LMG), initially a clinical description, includes an uncommon group of disorders characterized by a relentless, destructive process involving the upper respiratory structures. Its etiology and pathogenesis are uncertain, probably varied, and the distinction between inflammatory and malignant processes is difficult despite extensive clinical and histopathologic evaluation. The need for new techniques for rapid diagnosis has important therapeutic implications. Using an extensive panel of T- and B-cell monoclonal antibodies the authors describe a patient with clinically and pathologically typical LMG demonstrating an “activated” T-cell phenotype with a “novel” patterns characterstic of peripheral T-cell lymphoma, strongly implying that some cases of LMG are more closely related to neoplastic T-cell lymphoproliferative disorders than to inflammatory conditions. Further studies using these immunotyping techniques may help clarify the pathogenesis of LMG, and may uncover specific diagnostic and prognostic phenotypic patterns. Cancer 59:936-939, 1987.