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K Dicke

Publications and source records attributed to K Dicke.

At least 19 recordsLinked to original sources
PubMed1993

Methotrexate, cyclosporine, or both to prevent graft-versus-host disease after HLA-identical sibling bone marrow transplants for early leukemia?

Optimal prophylaxis of graft-versus-host disease (GVHD) is controversial. We compared efficacy of three posttransplant immune suppressive regimens in 2,286 recipients of HLA-identical sibling bone marrow transplants for acute lymphoblastic leukemia (ALL) in first remission, acute myelogenous leukemia (AML) in first remission, or chronic myelogenous leukemia (CML) in first chronic phase. Six hundred forty received methotrexate, 977 received cyclosporine, and 669 received combined cyclosporine and methotrexate. In children, the three regimens resulted in similar outcomes. In adults, cyclosporine and methotrexate had comparable risks of acute and chronic GVHD. Compared with methotrexate, cyclosporine was associated with less interstitial pneumonia (relative risk [RR] = 0.6; P < .001), less treatment-related mortality (RR = 0.6; P < .001), more relapses (RR = 1.6; P < .05), and less treatment failure (relapse or death from any cause; RR = 0.7; P < .001). Different effects were observed in different leukemias. In ALL, the rate of leukemia relapse was increased with cyclosporine versus methotrexate, with no effect on other outcomes. In AML and CML, interstitial pneumonia, treatment-related mortality, and treatment failures were decreased with cyclosporine, with no increase in relapse. Similar analyses comparing cyclosporine plus methotrexate with cyclosporine alone showed that adults receiving the combination had less acute GVHD (RR = 0.5; P < .001), less chronic GVHD (RR = 0.7; P < .01), and less interstitial pneumonia (RR = 0.7; P < .001). Treatment failure (RR = 0.8; P < .05) was marginally reduced. Separate analyses in ALL and AML showed less acute GVHD with combined therapy, but no significant effect on other outcomes. In CML, acute GVHD, interstitial pneumonia, treatment-related mortality, and treatment failure were decreased with combined therapy.

Adolescent↗
PubMed1993

A formal curriculum in breast imaging for radiology residents.

RATIONAL AND OBJECTIVES: Training in breast imaging is highly variable among radiology programs. The authors have developed a standardized breast imaging curriculum for radiology residents. METHODS: This curriculum has been implemented within the residency program at the University of North Carolina at Chapel Hill. It includes nine standardized components: 1) the clinical activities of the service; 2) the study of breast imaging teaching file films and contribution of new cases; 3) selected readings; 4) formal discussion with faculty on the readings; 5) review of this material using an interactive computer program; 6) formal conferences; 7) technical and quality control activities; 8) research activities; and 9) an evaluation. The participating residents have been surveyed regarding their opinions of their educational experience. RESULTS AND CONCLUSION: The standardized curriculum has been well received by the participating residents. Conclusions about the educational efficacy of such a curriculum cannot be made until more residents have used it.

Computer-Assisted Instruction↗
PubMed1993

Effects of delayed processing on mammographic phantom object detection.

OBJECTIVES: Delayed processing of films is a common occurrence in mobile mammography screening programs. The effects of such delayed processing on radiologists' detection of phantom test objects are investigated. METHODS: Twelve screen-film combinations were exposed using a phantom and developed after delays of 0, 1, 2, 3, 5, and 7 days. Films were scored by three board-certified radiologists specializing in mammography, based on visibility of calcifications, masses, fibrils, and line pairs. RESULTS: Variance analyses of mean scores indicate that, across screen-film combinations, there are no statistically significant decreases in object detection associated with delayed processing. The analyses do indicate, however, a statistically significant difference in scores unrelated to delay, attributable to the screen-film combination used. CONCLUSIONS: Delayed processing of mammography film does not lead to a decrease in the visibility of phantom test objects, despite large decreases in overall image optical density.

Analysis of Variance↗
PubMed1992

Influence of mobilized peripheral blood cells on the hematopoietic recovery by autologous marrow and recombinant human granulocyte-macrophage colony-stimulating factor after high-dose cyclophosphamide, etoposide, and cisplatin.

Peripheral blood cells (PBC) can hasten hematopoietic recovery after high-dose chemotherapy. To determine if PBC apheresed after mobilization further enhance hematopoietic recovery over that achieved with autologous bone marrow (ABM) and recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF), 14 patients with metastatic solid tumors were supported by ABM and rhGM-CSF during the first course of high doses of cyclophosphamide, etoposide, and cisplatin (CVP) and 11 of these 14 patients by mobilized PBC with ABM and rhGM-CSF during the second CVP. Each patient served as his or her own control. Identical doses of CVP were administered in both courses: cyclophosphamide 5.25 g/m2, etoposide 1,200 mg/m2, and cisplatin 165 to 180 mg/m2. PBC were collected on day 10 after mobilization with cyclophosphamide (3 g/m2) intravenously (IV) on day 1, doxorubicin (50 mg/m2) as a continuous IV infusion over 48 hours starting day 2, and rhGM-CSF as a daily 4-hour IV infusion starting day 4 at 0.6 mg/m2 for 14 days. Comparing recovery in the 11 patients to receive two cycles of therapy, the median days to an absolute neutrophil count of 0.1 x 10(9)/L and 0.5 x 10(9)/L were not statistically significant between the two courses; neither was there a difference in the incidence of fever and bacteremia. The median number of days to platelet count of 0.02 x 10(12)/L unmaintained by platelet transfusion was 20 from marrow infusion for course 1 and 16 for course 2 (P = .059). The median number of days to a platelet count of 0.05 x 10(12)/L was significantly shortened: 24 and 19 days for courses 1 and 2, respectively (P = .045). Patients who received PBC required fewer number of platelet transfusions. Extramedullary toxicities were not different between the groups. Our finding of enhanced early recovery of platelets and reduced platelet transfusion requirement is in concordance with other studies.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

Intensive combination chemotherapy and autologous bone marrow transplantation leads to the reappearance of Philadelphia chromosome-negative cells in chronic myelogenous leukemia.

Fifteen patients with Philadelphia chromosome (Ph)-positive chronic myelogenous leukemia (CML) who were ineligible for allogeneic bone marrow transplantation (BMT) or alpha-interferon therapy were included in this study. Eight patients were in the first late chronic phase, five were in the second chronic phase, one was in the accelerated phase, and one was in the blastic phase. Autologous bone marrow cells (median, 2.5 x 10(8) nucleated cells/kg) were stored at a median of 30 months after diagnosis. Patients were treated with cyclophosphamide (1.5 g/m2 daily for 4 days), carmustine (BCNU) (300 mg/m2), and etoposide (VP-16) (250 mg/m2 daily for 3 days) (CBV), followed by reinfusion of autologous bone marrow. Hematopoietic recovery was rapid, and toxicity was mild to moderate in 14 patients. One patient died of cytomegalovirus pneumonitis. Eight of 15 patients showed Ph suppression to less than 90% Ph-positive metaphases after autologous BMT. Major cytogenetic responses (Ph suppression to less than 35% Ph-positive metaphases) developed in four patients. Cytogenetic responses were observed in 4 of 11 patients infused with 100% Ph-positive marrows, and in all 4 patients infused with Ph-mosaic marrows (mixture of diploid and Ph-positive cells). Better results were observed when autologous BMT was performed in the chronic phase compared with the advanced phases. The major cytogenetic responses have lasted for 3, 4, 12, and 15+ months, whereas minor cytogenetic responses lasted for only a short time (less than 2 months). Three of seven patients (43%) in the chronic phase with previous resistance to alpha-interferon therapy became sensitive to alpha-interferon therapy after autologous BMT. The authors concluded that intensive chemotherapy followed by autologous BMT produced cytogenetic remissions in patients with Ph-positive CML and reinduced disease sensitivity to alpha-interferon therapy in patients previously resistant to it. This is particularly useful when treatment is given during the chronic phase and stem cells are collected at a time of previous cytogenetic remission.

Adult↗
PubMed1991

Impact of autologous bone marrow infusion on hematopoietic recovery after high-dose cyclophosphamide, etoposide, and cisplatin.

Because of potential tumor contamination and inadequacy of current purging technique of bone marrow in patients with solid tumors, we investigated an alternative approach to high-dose therapy without autologous bone marrow (ABM) infusion. Three levels of nonmyeloablative doses of cyclophosphamide 4.5 to 5.25 g/m2, etoposide 750 to 1,200 mg/m2, and cisplatin 120 to 165 mg/m2 (CVP) were administered to patients with metastatic solid tumors. Patients were randomized to ABM (n = 46) or no-ABM (NABM) (n = 46) infusion after CVP to study the impact of ABM on hematopoietic recovery, morbidity, and mortality. All patients had ABM harvested, underwent conventional chemotherapy, and then received CVP. Seventy-three patients received two courses of similar doses. The following were the median days to absolute neutrophil count (ANC) of 0.1 x 10(9)/L: for the ABM arm, 19, 21, and 19 and for the NABM arm, 23, 20, and 21 at levels 1, 2, and 3, respectively, during course 1 (P = .01, .80, and .01, respectively). During course 2, ANCs to 0.1 x 10(9)/L and 0.5 x 10(9)/L were attained significantly faster at levels 1 and 3 in the ABM arm. ANC to 1.0 x 10(9)/L was comparable in both arms. Incidence of infection and duration of fever were similar in both arms. Although mortality and the incidence of delayed hematopoietic recovery were more frequent in the NABM arm, this was not statistically significant. Platelet recovery was consistently prolonged in course 2 in both arms, with demonstrable benefit of ABM in course 2 when dose levels were collectively considered. We conclude that (1) ABM enhanced recovery of ANC to 0.1 x 10(9)/L; (2) ABM did not decrease the incidence of infections and the duration of fever; and (3) CVP can be safely given without ABM to carefully selected patients.

Adult↗
PubMed1990

Autologous bone marrow transplantation in multiple myeloma: identification of prognostic factors.

Multiple myeloma remains a universally fatal malignancy with a median survival time not exceeding 3 years. A clinical trial was undertaken to determine feasibility and efficacy of marrow-ablative chemoradiotherapy supported by unpurged autologous bone marrow (ABMT) and to define prognostic variables. Total body irradiation and either melphalan or thiotepa were administered to 55 patients (median age 53 years; range 20 to 66 years). The group of 21 patients with resistance to standard melphalan-prednisone and to continuous infusions of vincristine and Adriamycin with high dose dexamethasone (VAD) included 7 with primary unresponsive disease and 14 with resistant relapse; among the 34 patients achieving remission with the VAD regimen, 14 were in first and 20 in a subsequent remission. Marked cytoreduction by greater than or equal to 75% was observed among all 21 patients with refractory myeloma, whereas further cytoreduction of this magnitude was noted in only 56% of the 34 patients already in remission after VAD. Five of the 6 early deaths among all 55 patients occurred in the 14 patients with resistant relapse, none of whom achieved complete remission and who, as a group, had median durations of relapse-free and overall survival of only 8 and 7 months, respectively. Among the 41 remaining patients, there was only one early death, and 27% achieved complete remission including a 36% incidence among the 14 patients treated in first remission; their projected 4-year survival rate was 82% regardless of their disease status (first or later remission or primary resistance). When information about sensitivity to prior therapy is unavailable, the presence before ABMT of both high beta-2-microglobulin levels (greater than 3 mg/L) and non-IgG isotype helped identify 9 among the 55 patients with a very poor prognosis: all 8 responders relapsed within 9 months, and 8 patients died within 15 months. By contrast, a 4-year projected survival rate of over 70% for the other patients (about 80% of this series) justifies further investigation of this novel treatment approach in comparison with standard dose regimens. Our results indicate that marrow-ablative therapy cannot be recommended for myeloma patients with resistant relapse or those with a combination of risk factors (advanced tumor burden, absence of IgG isotype). The apparent lack of an adverse effect of even marked plasmacytosis in autografts (up to 30%) emphasizes the need for better cytoreduction rather than bone marrow purging.

Adult↗
PubMed1990

Use of recombinant human hematopoietic growth factors and autologous bone marrow transplantation to attenuate the neutropenic trough of high-dose therapy.

This manuscript summarizes our experience with recombinant human granulocyte colony-stimulating factor (rhG-CSF) with high-dose Cytoxan, carmustine and etoposide (CBV in Hodgkin's disease). rhG-CSF regularly shortened the neutropenic phase following autologous bone marrow transplantation. However, this effect was more marked on the latter part of neutrophil recovery than the early part of granulocyte recovery to 100 granulocytes/microliters. The frequency of afebrile episodes was not reduced by rhG-CSF administration, but there was a tendency for the duration of fever to be shortened. Increasing doses and continuous infusion did not hasten the early part of neutrophil recovery needed to prevent the onset of infection, but was more effective than bolus infusion in increasing the rate of late neutrophil recovery. If fevers are to be prevented in this patient population, the duration of an absolute granulocyte count of less than 100/microliters will have to last only a few days. Recombinant hematopoietic growth factors alone do not hasten recovery fast enough to prevent the onset of afebrile episodes. Studies are described using both recombinant growth factor and peripheral blood and bone marrow cells to see if the neutropenic trough can be further shortened over that achievable with growth factor and autologous transplant alone.

Agranulocytosis↗
PubMed1990

Results of the vincristine, doxorubicin, and dexamethasone regimen in adults with standard- and high-risk acute lymphocytic leukemia.

One hundred five untreated adult patients with acute lymphocytic leukemia (ALL) were entered on the vincristine, Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH), and Decadron (dexamethasone; Merck Sharp and Dohme, West Point, PA) (VAD) regimen. Induction therapy with VAD and VAD plus cyclophosphamide (CVAD) was followed by a 2-year rotating maintenance program with multiple antileukemic combinations, and included early intensifications with Adriamycin and high-dose cytarabine (ara-C) and a late intensification with cyclophosphamide, carmustine (BCNU), and etoposide (VP-16) (CBV) followed by autologous bone marrow transplantation (BMT). Duration of therapy was 24 to 30 months. Eight-eight patients (84%) achieved complete remission (CR) with VAD-CVAD, and 94 (90%) ultimately had CR with continuation of the maintenance as planned. Induction mortality was 3%; only half of the patients required prolonged hospitalization of 1 week or longer, or intravenous antibiotics. Maintenance therapy was given to 79 patients, while nine with histocompatibility locus antigen (HLA)-matched related donors underwent allogeneic BMT. The median remission duration was 22 months, and the median survival was 19 months. Factors associated with significantly worse CR rates were older age, the presence of hypoalbuminemia or hyperbilirubinemia, L2 or L3 morphology, and myeloid markers on leukemic cells. Those associated with significantly worse remission durations were the presence of elevated leukocyte or absolute peripheral blast counts, Philadelphia chromosome (Ph)-positive or B-cell ALL, L2 morphology, and more than one course to achieve CR. Patients could be divided into standard-risk ALL (28% of patients) and high-risk ALL (72% of patients) with long-term remission rates of 70% versus less than 30%. The 26 patients who underwent CBV autologous BMT had similar long-term outcome compared with 21 patients who did not (older age, medical contraindications, or socioeconomic problems). The presence or absence of myeloid markers on leukemic cells did not affect long-term prognosis. We conclude that VAD therapy is a well-tolerated effective induction regimen. High-risk ALL patients require alternative maintenance investigational approaches.

Adolescent↗
PubMed1988

A comparison of marrow transplantation with chemotherapy for adults with acute leukemia of poor prognosis in first complete remission.

From July 1980 to November 1985, 109 patients with acute myelogenous and lymphoblastic leukemia who had reached a complete remission (CR) following induction treatment were assigned to a study comparing marrow transplantation with chemotherapy as a postremission treatment. Sixty-nine patients did not have a human leukocyte antigen (HLA)-identical donor, and therefore served as chemotherapy controls; 40 patients had HLA-identical donors, and therefore were assigned to the transplant arm. Of these, 23 were transplanted in first remission and 17 were not. Ten of these 17 were subsequently transplanted in relapse. Initially, only patients with poor prognosis determined by a predictive model were entered into the study. Subsequently, patients with moderately poor prognosis were admitted. Comparing the chemotherapy group with the patients transplanted in first CR, significant control of leukemia relapse in transplanted patients was seen in the subgroup with acute myelogenous leukemia (AML) (P less than .1), and acute lymphoblastic leukemia (ALL) (P less than .01), in the poor (P = .01) and intermediate subgroup (P = .01), and in the good-prognostic groups (P = .05). The survival was affected significantly in only the poor and intermediate subgroups. The use of predictive models might help to select patients for whom bone marrow transplantation is appropriate in first remission and those for whom bone marrow transplantation can be left as the initial treatment of relapse. Predictive models could further be helpful in comparing studies performed at different transplant centers.

Adolescent↗
PubMed1988

myc and sis expression in acute myelogenous leukemia.

Several oncogenes have been reported to be expressed in normal and malignant hematopoietic cells. Since these studies have almost exclusively been done by Northern and dot blot hybridization techniques using mixed populations of cells, any conclusions concerning quantitative changes in gene expression are difficult to document. We have developed a rapid and sensitive RNA-in situ hybridization technique permitting detection of as few as five copies of mRNA per cell. Using this technique we have studied the expression of two genes, c-myc and c-sis, in acute leukemia patients as well as hematologically normal individuals. We have found that expression levels of myc and often sis are higher (greater than 5-fold) in hematopoietic cells obtained from leukemia patients than in normal hematopoietic cells. In regenerating marrow, there is a dramatic increase in the frequency of cells expressing myc at the level of five to 10 copies without the presence of any cells expressing myc at the high levels found in acute leukemia. This is completely different from leukemic remission marrow in which we find a subpopulation of cells which express myc at very high levels. At this time, the leukemic origin of this abnormal cell population is likely because of the close correlation we find between gene overexpression and leukemic phenotype as identified by double-labeling experiments. It appears that gene overexpression may be a more sensitive or an earlier marker for leukemic cells and that such an assay could be used in the detection of residual disease.

Bone Marrow↗
PubMed1988

Prognostic factors with high-dose melphalan for refractory multiple myeloma.

High doses of melphalan (HDM) and dexamethasone were administered to 43 patients with advanced multiple myeloma, 36 of whom were refractory to both standard melphalan-prednisone and vincristine-adriamycin-dexamethasone (VAD). Forty-four percent responded with greater than 75% reduction in calculated tumor mass, including three patients who achieved a complete remission. The response rate to HDM was 56% in 18 relapsing patients and 50% in 12 patients with less than 12 months of primary drug resistance, but it was only 23% among the remaining 13 unresponsive patients. A high early mortality rate of 30% was confined to 26 patients with either poor performance (Zubrod greater than 1) or impaired renal function (creatinine greater than 1.4 mg%). When this toxic treatment was given to the 21 patients with good performance (Zubrod less than 2) whose disease lacked high serum lactic dehydrogenase (less than or equal to 500 U/L) as a recently recognized feature of high-grade myeloma, a superior median survival of 18 months was obtained as opposed to only 3 months for the 22 remaining patients (P less than .001). Thus, when employed in a timely fashion, HDM overcomes resistance to standard chemotherapy and VAD and benefits selected patients with advanced myeloma.

Aged↗
PubMed1986

In vitro cytotoxicity patterns of standard and investigational agents on human bone marrow granulocyte-macrophage progenitor cells.

Inhibitory concentrations (ICs) against human bone marrow granulocyte-macrophage colony forming cells (GM-CFC) were established for 26 cancer chemotherapy agents, including seven investigational agents by ten day exposure. Each drug was tested at four or more concentrations to generate reliable survival curves. The analysis of the survival curves produced three patterns according to which drugs were classified: class A drugs had a shouldered curve with terminal exponential kill of GM-CFC, class B drugs produced initial exponential component followed by a plateau, and class C drugs produced linear curves. These categories provide the relationship between drug concentration and cytotoxicity, e.g., the cytotoxicity of class B drugs, after initial kill, did not increase in spite of serial doubling of concentrations whereas the class C drugs had proportional killing with two-fold concentration increment. A number of drugs were active at in vitro concentrations of less than or equal to 0.01 microgram ml-1 and caused log reduction of GM-CFC with an approximate concentration of 0.0001 microgram ml-1. Drugs known to require in vivo bioactivation, namely dacarbazine, procarbazine, and ifosfamide were active at high concentrations (greater than 10.0 micrograms ml-1). We propose that for myelosuppressive agents the GM-CFC provides a useful biologic reference to determine in vitro cut off concentrations to be utilized for drug screening. For nonmyelosuppressive agents, however, it may be suboptimal.

Antineoplastic Agents↗
PubMed1986

High-dose intensification therapy with autologous bone marrow support for limited small-cell bronchogenic carcinoma.

The efficacy and toxicity of high-dose chemotherapy with autologous bone marrow transplantation (ABMT) was studied in 32 patients with untreated limited small-cell bronchogenic carcinoma (SCBC). Ten patients received three courses of induction therapy consisting of vincristine (VCR) (1.5 mg X 2), ifosfamide (5 g/m2), and Adriamycin (Ad; Adria Laboratories, Columbus, Ohio) (60 mg/m2). Patients then received two courses of intensification therapy with cyclophosphamide (CYT) (4.5 g/m2), 4' demethyl-epipodophyllotoxin-d-D-ethylidene glucoside (VP-16-213) (600 mg/m2) and VCR (2 mg) with ABMT. Another 22 patients received induction therapy with VCR, CYT (600 mg/m2), Ad (50 mg/m2), and VP-16-213 (180 mg/m2). All 22 patients also received intensification therapy of the same dose of CYT (4.5 g/m2) and VP-16-213 (600 mg/m2). Nine patients also received high-dose methotrexate (MTX), four patients received Ad (40 to 60 mg/m2), and two patients received both Ad and MTX. After intensification, patients received elective prophylactic brain irradiation (3,000 rad) and chest irradiation (5,000 rad). After induction therapy, there were 13 (41%) complete remissions (CR) and 17 (53%) partial remissions (PR). After intensification therapy, there were 22 CRs (69%) and 10 PRs (31%). Median survival for all patients was 14 months (range, 5 to 59+). Of the 13 patients who received intensification therapy in CR, five remain disease free (DF), four for 4 years or longer. Of the nine patients to achieve CR with intensification, only one is DF. No patient died during intensification. In conclusion, intensification with high-dose chemotherapy can increase the CR rate, and this approach is most likely to show long-term benefits in patients with minimal disease (CR) at the beginning of intensification therapy.

Adult↗
PubMed1986

Potential drugs for elimination of acute lymphatic leukemia cells from autologous bone marrow.

Five drugs, selected because of minimal in vivo myelotoxicity, have been investigated for inhibition of the growth of three acute lymphatic leukemia-derived cell lines. Granulocyte-macrophage colony-forming units (GM-CFU) inhibition with these five drugs after 60-min incubation was first established. Drug concentrations giving up to 90% kill of GM-CFU were then used. Spirogermanium and L-asparaginase did not have an effect on any of the three cell lines under the culture conditions tested, while 4-hydroperoxycyclophosphamide (4-HC) and vincristine inhibited the growth of all three cell lines tested, and bleomycin inhibited the growth of two cell lines. In addition to 4-HC, bleomycin and vincristine should be considered as possible agents in eliminating leukemic cells from autologous marrow grafts. These drugs also deserve further investigation in clonal systems.

Antineoplastic Agents↗
PubMed1986

High-dose melphalan with autologous bone marrow transplantation for multiple myeloma.

A large dose of melphalan was given to 23 patients with advanced multiple myeloma that was refractory to multiple prior treatments. Sixteen patients received a dose of 80 to 100 mg/m2, and seven were given 140 mg/m2 followed by autologous bone marrow infusion. Tumor mass was reduced by more than 75% in 14 patients, including four who died of bone marrow aplasia. Serious infections were prevented in six of seven patients who received autologous bone marrow. The marked cytoreduction in patients with previously refractory disease indicated the apparent drug resistance could be overcome by dose escalation. However, short remission times in most responding patients were consistent with rapid regrowth of primordial tumor cells with high proliferative activity. Although high-dose melphalan was of limited benefit to patients with refractory myeloma, further studies are necessary to clarify its role during earlier phases of disease.

Adult↗
PubMed1984

High-dose chemotherapy with autologous bone marrow transplantation.

High-dose chemotherapy using drugs with predominant marrow toxicity and autologous bone marrow support has been investigated in a number of tumor types. High response rates are uniform and complete responses are also high; but long-term disease-free survival is occasional. This review discusses those tumor types where patients treated with this approach have survived disease free for several years. Also discussed is what other tumor types and prognostic subgroups of those tumors might benefit therapeutically from high-dose cytotoxic intensification with autologous bone marrow support or at least have this approach considered as the first alternative for initial relapse.

Antineoplastic Agents↗