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Biomedical subjects

R T Silver

Publications and source records attributed to R T Silver.

At least 73 records · Page 4Linked to original sources

A comparative study of dibromomannitol and busulfan in the treatment of chronic myeloid leukemia. A study of cancer and leukemia group B.

In a prospective, randomized trial the effectiveness of dibromomannitol (DBM), a brominated sugar alcohol derivative, was compared to busulfan in previously untreated patients. One hundred thirty-one patients were evaluated for response and survival. The effective dose of DBM was 4 mg/kg. The persistence of sensitivity to either DBM or busulfan was shown in a quantified fashion. Despite initial reports of the alleged unique effectiveness of DBM in treating chronic myeloid leukemia (CML), this study did not disclose any advantage of DBM over busulfan. Multivariate analysis investigating the importance of prognostic factors in CML indicated that age, sex, splenomegaly, and initial platelet count were important for predicting survival. Determination of such factors in CML are valuable in deciding those patients who could benefit from alternative forms of therapy. It also insures that study results are related to treatment rather than selection of patients with favorable or unfavorable prognostic factors.

Adolescent↗

Adoptive immunotherapy for stage IV renal cell carcinoma: a novel protocol utilizing periodate and interleukin-2-activated autologous leukocytes and continuous infusions of low-dose interleukin-2.

In a pilot study involving 13 patients with advanced stage IV renal cell carcinoma, anti-tumor effects and toxicity of a novel form of adoptive immunotherapy were determined. The protocol utilizes infusions of autologous mononuclear leukocytes treated with the oxidizing mitogen sodium periodate (IO4-) and cultured in medium containing human recombinant interleukin-2 (IL-2), and continuous infusions of low-dose IL-2 (mean +/- SD dose = 39.5 +/- 8.6 X 10(3) U/kg/24 hours). Leukocytes (5 to 10 X 10(9] were removed by leukapheresis three times per week, mononuclear cells were separated, activated with IO4- and cultured in medium containing IL-2 (500 U/ml) for 48 to 72 hours. The cells were re-infused following the next leukapheresis procedure. IL-2 was administered five days per week. Treatment was continued for two three-week cycles. An increase in peripheral blood mononuclear cells bearing the natural killer cell (NK) surface marker, Leu 11, an increase in NK- and antibody-dependent cell-mediated cytotoxicity, and a slight increase in spontaneous cytotoxicity for non-NK targets were noted. Regressions (more than 50 percent decrease in tumor mass) of pulmonary, liver, bone, or soft tissue metastases were induced in six patients. Severe fluid retention did not develop in any patient and no patient required treatment in the intensive care unit. Five of the patients who showed a response have experienced a relapse at 5.2 +/- 1.0 (mean +/- SD) months. These observations indicate that IO4-/IL-2-activated killer cells plus continuous infusions of low-dose IL-2 can result in regression of metastatic renal cell carcinoma.

Adult↗

Utility of molecular genetic analysis of bcr rearrangement in the diagnosis of chronic myeloid leukemia.

Two DNA probes for the breakpoint cluster region (bcr) of chromosome # 22 have been used to determine the proportion of Philadelphia chromosome (Ph)-positive chronic myeloid leukemia (CML) cases that can be diagnosed by Southern blot analysis. Studies on 17 normal individuals and 17 patients with lymphomas and leukemias (other than CML) indicated that for the restriction enzymes chosen, only expected germ line DNA bands were obtained. In contrast, novel DNA bands interpreted as being the product of translocation within the bcr region could be demonstrated in 31 of 31 cases of Ph-positive CML. One commercially available 1.2 kb bcr probe detected most cases of CML. Because of the frequent presence of deletion of part of the bcr region, however, a probe from the 5' end of bcr is essential to detect some cases. An analysis of the bcr breakpoints occurring in CML patients suggested a difference in the location of the breakpoints for the blast crisis patients versus chronic phase patients although the difference between these two groups was not statistically significant. It is concluded that bcr analysis provides a powerful aid in the diagnosis of CML. This technique is of particular merit in cases when cytogenetic analysis is inconclusive and has considerable potential for improved speed and sensitivity of diagnosis.

Chromosome Banding↗

Length polymorphisms of the human Y chromosome in patients with chronic myelogenous leukemia.

The extent of length heteromorphisms of the human Y chromosomes was measured in 50 patients with chronic myelogenous leukemia and was compared with 50 normal controls. No significant difference (p greater than 0.05) in the size of the Y chromosome was noted between these two groups. These findings differ from an earlier investigation, where a longer heterochromatic segment of Y chromosome was noted in malignant tumors and it was stressed that constitutive heterochromatin plays a role in susceptibility of cancer. Present investigation, however, suggests that this is not the case in patients with chronic myelogenous leukemia.

Heterochromatin↗

Advances in chemotherapy for large cell lymphoma.

Three generations of chemotherapy regimens for the treatment of aggressive lymphomas have evolved in the past decade. The first-generation combination regimen, CVP, also known as COP (cyclophosphamide, vincristine, prednisone), produced maximum long-term survivals in considerably less than 20% of patients. With the MOPP (mechlorethamine, vincristine, procarbazine, prednisone) regimen, 40% of patients achieved complete remission (CR). This signal study was paralleled by other first-generation studies including CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone), HOP (doxorubicin, vincristine, prednisone), CHOP-Bleo/BACOP (CHOP plus bleomycin), and COMLA (cyclophosphamide, vincristine, methotrexate, leucovorin, cytarabine). None of the regimens was shown to be particularly superior to the others. Survival plateaus were seen in approximately 20% to 40% of patients. Second-generation therapies, COP-BLAM (cyclophosphamide, vincristine, prednisone, bleomycin, doxorubicin, procarbazine), ProMACE-MOPP (prednisone, methotrexate, doxorubicin, cyclophosphamide, etoposide, mechlorethamine, vincristine, procarbazine, prednisone), M-BACOD (methotrexate, bleomycin, doxorubicin, cyclophosphamide, vincristine, dexamethasone), and m-BACOD (same as M-BACOD, but with a moderate dose of methotrexate and modified leucovorin given on days 8 and 15 instead of just day 10) were characterized by an increasing number of drugs, more frequent administration of myelosuppressive agents, and flexible dose schedules. This new treatment intensity resulted in CRs in excess of 70%. The third generation regimens have been characterized by innovative concepts of chemotherapy, including alternative modes of drug administration, greater use of marrow-sparing, cycle-active, and/or putatively non-cross-resistant agents, and more frequent and/or intense dose administration. These regimens, COP-BLAM III, MACOP-B (methotrexate, doxorubicin, cyclophosphamide, vincristine, prednisone, bleomycin), ProMACE-CytaBOM (ProMACE plus cytarabine, bleomycin, vincristine, methotrexate), and high-dose doxorubicin with cytarabine, have produced over 80% CRs and survival plateaus in excess of 60%. In the COP-BLAM III regimen, 84% of patients achieved a pathologic CR. Overall, 65% of patients are alive, well, and free of disease, and potentially in the survival plateau. COD-BLAM IV (same as COP-BLAM, except dexamethasone is substituted for prednisone) is a new program that further intensifies treatment by using sequential, rather than alternate-cycle, infusions of bleomycin and vincristine. Results are still preliminary, with a short median follow-up of 19 months.(ABSTRACT TRUNCATED AT 400 WORDS)

Age Factors↗

Role of heterochromatin during preferential 9q;22q translocation in chronic myelogenous leukemia.

The secondary constriction region (h) of human chromosome 9 was evaluated in 55 chronic myelogenous leukemia (CML) patients with respect to its size and position. Each case was examined by C-banding and distamycin A-4,6-diamidino-2-phenylindole techniques for the expression of the h regions. When one h region of chromosome 9 was larger, it was more frequently involved in the reciprocal translocation with chromosome 22. In addition, there was a higher incidence of pericentric inversions in the h regions in the translocated chromosome 9 when compared with normal homologues. The role of the constitutive heterochromatin of chromosome 9 as a possible influencing factor during 9q;22q translocation in CML is suggested.

Chromosome Banding↗

HAC-Cytoxan (cyclophosphamide) chemotherapy for ovarian carcinoma. Alternating chemotherapy with intensification.

Twenty-two previously untreated patients with adenocarcinoma of the ovary were treated with 28 day cycles of hexamethylmelamine, Adriamycin (doxorubicin), and cisplatin (HAC) for 9 months followed by three monthly cycles of intense intravenous cyclophosphamide. An overall response frequency of 82% (18/22) was achieved. Complete pathologic responses (CPR) documented by second look operations were found in 50% (11/22); however, patients considered to be free of disease (prolonged complete clinical response refusing "second look" and CPR) totaled 59%. Median survival has not been reached after a median follow-up of 34 months. No major or life threatening toxicity was encountered. HAC followed by cyclophosphamide is a highly effective regimen that may be easily administered on an outpatient basis with comparatively little toxicity.

Adenocarcinoma↗

Unusual translocations involving chromosomes 12;22 and 9;12 in a case of chronic myelogenous leukemia.

A case of chronic myelogenous leukemia (CML) with highly unusual translocations involving both chromosomes #12 is reported. The origin of the Ph1 chromosome was due to a 12p/22q translocation. Chromosome #9 was involved in a translocation with the other chromosome #12. By critical examination of the "size" of the Philadelphia chromosome, it was noted that the breakpoints on 22q were different when compared with a previous case (see Verma and Dosik [16]), although the short arm of chromosome #12 (12p) was involved in both instances. So far, no apparent differences in the course of the disease have been attributed to the types of translocation observed in these cases.

Adult↗

Six-drug chemotherapy (hexamethylmelamine, doxorubicin, cisplatin, cyclophosphamide, methotrexate, and 5-FU; CHAMP-5) for ovarian carcinoma: alternating sequences of combination regimens.

Twenty-five patients with previously untreated adenocarcinoma of the ovary (International Federation of Gynecology and Obstetrics, stages II, III, and IV) were placed on a six-drug trial (CHAMP-5) for 18 months. This trial consisted of 28-day cycles of hexamethylmelamine, doxorubicin, and cisplatin alternating with hexamethylmelamine, cyclophosphamide, methotrexate, and 5-FU. After a minimum follow-up of 31 months, 14 (56%) of the 25 evaluable patients achieved complete or partial response and nine (36%) achieved complete pathologic response. Although CHAMP-5 is effective in the treatment of ovarian cancer, the results in these patients are not substantially different from those achieved with hexamethylmelamine, doxorubicin, and cisplatin alone.

Adenocarcinoma↗

Treatment of advanced endometrial carcinoma with doxorubicin and cisplatin: effects on both untreated and previously treated patients.

Sixteen patients with advanced (International Federation of Gynecology and Obstetrics stage III and IV) adenocarcinoma of the endometrium were treated with twelve 28-day cycles of doxorubicin and cisplatin. Response was achieved in 92% of patients (11 responses among 12 patients) who had received no prior chemotherapy and in 50% (two responses among four patients) of previously treated patients. Median survival was 10 months. Doxorubicin and cisplatin were readily administered on an outpatient basis with comparatively low major toxic effects, primarily hematologic, renal, and gastrointestinal. These results indicate that doxorubicin and cisplatin combination therapy is effective with acceptable toxicity in patients with advanced endometrial carcinoma.

Adult↗

Treatment of advanced ovarian carcinoma with hexamethylmelamine, doxorubicin, and cis-platinum (HAC): results in both untreated and previously treated patients.

Twenty-two patients with advanced (FIGO stages III and IV) adenocarcinoma of the ovary were treated with 28-day cycles of hexamethylmelamine, doxorubicin, and cis-dichlorodiamine-platinum (II) (HAC). After 45 months, there were 21 evaluable patients. The median survival was 16 months. Response was achieved in 82% (9/11) who had received no prior chemotherapy, and in 50% (5/10) previously treated. HAC therapy was readily administered on an outpatient basis, with comparatively low major toxicities, primarily hematologic, neurologic, and gastrointestinal. These results indicate that HAC therapy is an effective regimen for patients with advanced ovarian carcinoma, regardless of their prior treatment status.

Adenocarcinoma↗

A comparison of intermittent vs. continuous and of adriamycin vs. methotrexate 5-drug chemotherapy for advanced breast cancer. A Cancer and Leukemia Group B study.

The therapeutic effectiveness of intermittent vs. continuous combination chemotherapy and of the substitution of adriamycin for methotrexate in a 5-drug regimen was evaluated in women with metastatic breast carcinoma. Patients were randomly allocated to receive continuous therapy with cyclophosphamide, methotrexate, 5-fluorouracil, vincristine, prednisone ( CMFVP -C, 86 patients), intermittent CMFVP ( CMFVP -I, 109 patients), or intermittent CAFVP (107 patients). The CR + PR rate with CAFVP (71%) was superior to CMFVP -C (50%, p = 0.003) and to CMFVP -I (50%, p = 0.002). The remission duration with CAFVP (14 months, median) was superior to CMFVP -I (7 months) (p less than 0.01), and tended to be superior to CMFVP -C (9 months) (p = 0.07). There was a survival advantage of CAFVP (19 months, median) over CMFVP -I (13 months) (p = 0.01), but not over CMFVP -C (16 months) (p = 0.24). Among CR + PR patients, the survival with CAFVP (29 months, median) was superior (p = 0.02) to both CMFVP -I (18 months) and CMFVP -C (21 months). The CMFVP -C regimen was associated with the highest incidence of leukopenia and neurologic toxicity, but the lowest incidence of GI toxicity. The results indicate that the CAFVP regimen is well tolerated and is superior to the CMFVP regimens.

Age Factors↗

Efficacy of daunorubicin in the therapy of adult acute lymphocytic leukemia: a prospective randomized trial by cancer and leukemia group B.

The efficacy of the addition of intensive therapy with daunorubicin (45 mg/m2 IV on days 1, 2, 3) to an otherwise identical induction program consisting of vincristine, prednisone, and L-asparaginase was assessed in 177 previously untreated adults (greater than or equal to 20 years of age) with acute lymphocytic leukemia (ALL). In the prospectively randomized phase of the investigation, 46 patients received daunorubicin in induction, whereas 53 did not. The two groups were otherwise comparable for pretreatment variables. A complete response was observed in 38/46 patients (83%) treated with daunorubicin, compared to 25/53 (47%) induced with vincristine, prednisone, and L-asparaginase alone (P = .003). The high response rate attributable to the use of the anthracycline was confirmed by the nonrandomized treatment of 78 subsequent patients, in whom a complete response rate of 76% was attained. A common program for central nervous system therapy and for maintenance therapy was employed in 103 patients achieving complete response. Maintenance consisted of cycles of 6-mercaptopurine (6-MP) and methotrexate with periodic reinforcement with vincristine and prednisone. Maintenance therapy proved to be minimally toxic. The average duration of complete response was 15 months and was not affected by the induction program employed. Approximately 25% of responders are projected to remain in continuing complete response for 36 months. The failure of the daunorubicin-containing programs to produce a higher percentage of long-term survivors, despite the higher complete response rates achieved, was thought to be due to the use of a maintenance program that was weak in intensity and dependent on reinforcement with vincristine and prednisone. These data clearly establish the increased effectiveness of vincristine, prednisone, L-asparaginase, and daunorubicin, as compared to this combination without daunorubicin, in the induction of complete response in adults with ALL. The results support the concept of an intensive, rather than a conservative, chemotherapeutic approach as the most appropriate strategy for the treatment of adult ALL.

Adult↗