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Results for “CITROVORUM FACTOR”

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PubMed1977

Regulatory control of tetrahydrofolate coenzymes in folate auxotrophs.

The interrelated enzymic reactions of folate metabolism are presented and key tetrahydrofolate-producing reactions are emphasized. As observed with the methotrexate (MTX)-resistant mutant strain Streptococcus faecium var. durans/Ak, the regulatory roles of serine and purines in controlling their own synthesis by the repression of enzymes required for co-factor synthesis are reviewed. Positive induction of the dihydrofolate reductase activity of this mutant by folate and the antagonism of the folate effect by purines and thymine are discussed. A protective agent of the reductase-active protein, MTX is viewed also as a "positive" inducer of dihydrofolate reductase. Preliminary studies with L1210 leukemia-bearing mice and the murine leukemia ERLD in vitro suggest that citrovorum factor (CF) also triggers a positive induction of the reductase of the small intestine and of ERLD cells without apparently influencing the reductase level of L1210 in vivo. The possibility that control mechanisms, by which MTX and CF indirectly regulate enzyme synthesis in drug-stressed, CF-rescued cells, contribute to the success of high-dose MTX-CF rescue therapy is introduced.

Animals↗

PubMed1975

The rationale for multiple drug chemotherapy in the treatment of osteogenic sarcoma.

Based on our prior experience in treating children with metastatic osteogenic sarcoma, a multidrug regimen was developed. Nine children with evaluable osteogenic sarcoma were treated with vincristine 1.5 mg/m2 on day 1, highdose methotrexate 200-300 mg/kg i.v. on day 2, with p.o. citrovorum factor "rescue" 9 mg every 6 hours x 12, followed in 2 weeks by cyclophosphamide 40 mg/kg i.v., then 2 weeks later Adriamycin 1.5 mg/kg/day x 2; in 2 weeks cyclophosphamide was repeated. After a 2-week rest, the 56-day cycle was repeated for a total period of 1 year. Oropharyngeal mucositis was the most frequent severe manifestation of gastrointestinal toxicity. Hematologic depression was mild to severe. Nine patients with clinically evaluable osteogenic sarcoma and no previous chemotherapeutic treatment were treated with this regimen. One patient had only a transient shrinkage in tumor mass, and one patient had no progression of multiple pulmonary and bone metastases for 16 months while on therapy. Of the remaining seven patients, all had clinically significant responses with tumor regression demonstrated for from 5 to 20+ months. Four of these patients (three presenting with primary tumor and pulmonary metastases) demonstrated regression of their primary tumor. In an attempt to increase the cure rate in osteogenic sarcoma, chemotherapy that has proven to be effective against metastatic osteogenic sarcoma should now be employed as prophylactic therapy, after amputation, at cancer treatment centers where it can be safely and effectively administered.

Adolescent↗

PubMed1975

The management of pulmonary metastases in children with osteogenic sarcoma with surgical resection combined with chemotherapy.

This report concerns a consecutive group of 10 children with metastatic osteogenic sarcoma treated with combined surgery and chemotherapy. Eight of 10 patients had thoracotomy prior to chemotherapy, and 2 after an initial trial of chemotherapy. Sequential chemotherapy was given to all patients and consisted of vincristine, high-dose methotrexate with citrovorum factor rescue, cyclophosphamide, and Adriamycin. Chemotherapy was continuously recycled for 1 year. The encouraging results obtained with these 10 patients are demonstrated with emphasis on the value of aggressive multidisciplinary therapy in salvaging patients with advanced metastatic osteogenic sarcoma.

Adolescent↗

PubMed1975

Combination chemotherapy and radiation therapy in the treatment of metastatic osteogenic sarcoma.

Fourteen patients with 16 metastatic ostogenic sarcoma lesions were treated with high-dose methotrexate (HDMTX) with citrovorum factor rescue (CFR), adriamycin, and pulse high-dose cyclophosphamide combined with radiation therapy. Thirteen of 16 lesions responded. Responses consisted of relief of pain (6/6 patients) in bone lesions, roentgenographic and clinical evidence of decrease in the size of the bone lesions (6/7 patients), and a decrease in the size of pulmonary metastases (2/4 patients). The 2 patients whose pulmonary metastases responded to combined therapy developed pulmonary fibrosis and pneumonitis in the treated areas 3 months after radiation therapy (RT) (1400 and 1600 rads respectively). Of two bulky primary tumors that appeared to respond, both were ultimately found to contain viable tumor; a third less bulky primary tumor appeared to respond more completely. Three smaller metastatic bone lesions that were ultimately biopsied showed no evidence of active tumor. It is concluded that: 1) combination therapy (particularly HDMTX and RT) has an additive effect in controlling osteogenic sarcoma bone lesions, but bulky primary tumors cannot be completely eradicated; 2) although synergistic in treating osteogenic sarcoma, combination therapy can produce enhanced toxicity in surrounding normal lung tissue; and 3) combination therapy is of value in the palliative treatment of metastatic lesions other than that of lung, and in the treatment of small primary bone lesions. However, experience to date does not justify the delay in surgical ablation of a primary lesion in a child who presents without metastatic disease.

Adolescent↗

PubMed1976

Chemotherapy, en bloc resection, and prosthetic bone replacement in the treatment of osteogenic sarcoma.

In an attempt to shrink primary osteogenic sarcoma and allow complete surgical removal of the primary tumor, without amputating the involved limb, intensive preoperative chemotherapy with high dose methotrexate (HDMTX) with citrovorum factor rescue (CFR) and adriamycin (ADR) was initiated in 20 patients with biopsy-proven primary osteogenic sarcoma of the distal femur (15 patients) and proximal tibia (five patients). Following intensive chemotherapy, en bloc resection of the primary tumor with prosthetic replacement of the involved bone was planned. After surgery, adjuvant chemotherapy, consisting of HDMTX with CFR, ADR, and high dose cyclophosphamide was given sequentially for 1 year. Of 20 patients with primary osteogenic sarcoma (two with evidence of pulmonary metastases), 18 had primary tumors that could be clinically measured. Of these 18, 17 demonstrated a decrease in the size of primary tumor prior to surgery, while on chemotherapy. To date, 12 of these patients with osteogenic sarcoma of the distal femur have had total femur and knee joint replacement, and three patients with osteogenic sarcoma of the proximal tibia have had total knee replacement. In all 15 patients, surgical margins were grossly and microscopically free of tumor. There has been no evidence of soft tissue recurrence in any of the 15 patients who have undergone surgery for from 2 to 15 months postoperatively. These preliminary results indicate that with the use of aggressive chemotherapy, it is possible to demonstrate objective tumor regression in primary osteogenic sarcoma, allowing the surgeon to perform en bloc resection of tumor and prosthetic replacement of the involved bone. Although the limb is preserved, it is important to stress that extensive surgery yielding tumor-free margins is performed. The ultimate evaluation of this approach to the treatment of primary osteogenic sarcoma awaits longer observation, to determine limb function and the continued disease-free status, once adjuvant chemotherapy is discontinued.

Adolescent↗

PubMed1977

Multiple basis of combination chemotherapy.

In combination chemotherapy, the type of drug interactions can be divided into three broad categories: 1) combinations based on cooperative effects of active drugs; 2) combinations in which the effectiveness of an active drug is increased by the concurrent administration of an inactive agent; and 3) combination of an active drug with an agent capable of selectively reversing the toxicity of the first drug. Many concepts have been proposed to explain the synergistic interaction between two active drugs at the level of the target cell. These include multiple inhibition of a single enzyme, enhanced activation, decreased inactivation, increased drug uptake, sequential blockade, concurrent inhibition, complimentary inhibition, and concerted inhibition. The therapeutic advantage of combination chemotherapy may reside in the whole organism, reflecting increased bioavailability of drug, reduced dose-limiting toxicity or reduced impairment of host defenses; it may reside in the tumor cells, reflecting the multiple molecular mechanisms of interaction mentioned above. Examples discussed include among others methotrexate plus citrovorum factor, thymidine or allopurinol, araC plus tetrahydrouridine and 3-deazauridine plus testosterone.

Animals↗

PubMed1979

Primary osteogenic sarcoma: the rationale for preoperative chemotherapy and delayed surgery.

From 1973--1975, 31 patients with biopsied primary osteogenic sarcoma were treated with preoperative chemotherapy followed by surgical ablation of the primary tumor. Surgery was delayed in order to obtain a custom-fitted prosthetic bone implant in an attempt to avoid amputation. Preoperative chemotherapy included high dose methotrexate (HDMTX) with citrovorum factor rescue (CFR) and adriamycin (T-5 protocol) and was administered for 3 months preoperatively and continued with the inclusion of cyclophosphamide for approximately 5 months postoperatively. At a follow-up period of 30--52 months, 23 of 31 patients (75%) are surviving (21 of 23 with no evidence of disease). Histologic examination of primary tumor removed at surgery revealed varying degrees of tumor destruction (from very little effect to no evidence of viable tumor) attributable to the effect of chemotherapy. The 21 patients that are disease-free survivors had a more complete effect of preoperative chemotherapy on the primary tumor. Some patients achieving favorable effects upon the primary tumor did so only after the dose of HDMTX was escalated to greater than the starting dose of 8 g/m2. Preoperative chemotherapy for all patients with osteogenic sarcoma would seem to offer the following advantages: 1) Evaluation of the effect of HDMTX with CFR on the primary tumor with escalation of the dose of HDMTX until a clinical response is observed, thus defining the dose of HDMTX effective in that patient, to be continued postoperatively as adjuvant therapy; 2) The early use of systemic therapy to eradicate distant microfoci of disease that will eventually kill the patient if not adequately treated by effective chemotherapy; 3) Allow more time for postoperative healing without the need to start adjuvant chemotherapy immediately; and 4) Provide the surgeon time to plan resection surgery. To date, 20 additional patients with biopsy proven osteogenic sarcoma have been treated with more aggressive preoperative chemotherapy (T-7) for approximately 2 1/2 months prior to definitive surgery (resection or amputation). Doses of HDMTX were escalated where necessary and good clinical responses were obtained in 19 of 20 patients. In the majority of patients, no evidence of viable tumor was found on histologic examination of the surgically removed primary tumor. All 20 patients are surviving free of active disease at this brief follow-up period of 4--20 months.

Adolescent↗

PubMed1980

High-dose methotrexate with "RESCUE" plus cyclophosphamide as initial chemotherapy in ovarian adenocarcinoma. A randomized trial with observations on the influence of C parvum immunotherapy.

In a prospective randomized study, the chemotherapeutic combination of high-dose methotrexate-citrovorum factor rescue plus cyclophosphamide (MECY) has been shown to be statistically significantly superior to the combination of 5-fluorouracil plus cyclophosphamide (FUCY) in the treatment of Stage III-IV ovarian adenocarcinoma. With MECY, an overall objective remission rate of 67% and a complete remission rate of 48% were achieved. All patients had undergone no treatment except for surgery. In addition to the chemotherapy, patients were randomly allocated to receive or not receive nonspecific immunotherapy with Corynebacterium parvum; this immunotherapy had no apparent effect on the chemotherapeutic response. The study demonstrates a high degree of activity for the MECY regimen, and a comparison between the results with MECY in this study and melphalan in an earlier prospective randomized study provides statistical evidence favoring MECY over single-agent melphalan in the treatment of this disease.

Adenocarcinoma↗

PubMed1981

Methotrexate: an active drug in bladder cancer.

Forty-nine patients with transitional urothelial tract tumors received methotrexate: 0.5-1.0 mg/kg I.V. Q W (40 patients) or 250 mg/M2 in a 2-hour infusion with citrovorum factor rescue 24 hours later (nine patients). Eleven (26%, 95% confidence limits 13-39%) of 42 patients with bidimensionally measurable metastases achieved partial remission. Most responses occurred within 2-3 weeks and persisted for a median duration of six months (range, 2-20). Response rates were increased to 38% (6/16 patients, 95% confidence limits 18-65%) in patients who had no prior chemotherapy, and a 90-100% performance status (50, 5/10 patients, 95% confidence limits 22-78%) compared with 19% (5/26, 95% confidence limits 8-37%) in patients who had prior chemotherapy and a less than or equal to 80% performance status (19%, 6/32 cases, 95% confidence limits 9-32%). Toxicity included mucositis and myelosuppression. A review of the literature coupled with the present data suggest that methotrexate is as active as cisplatin in the treatment of patients with advanced urinary bladder cancer.

Adult↗

PubMed1982

Preoperative chemotherapy for osteogenic sarcoma: selection of postoperative adjuvant chemotherapy based on the response of the primary tumor to preoperative chemotherapy.

Since June 1978, 57 patients with primary osteogenic sarcoma of an extremity were treated with high-dose methotrexate (HDMTX) and citrovorum factor rescue (CFR), Adriamycin, and the combination of bleomycin, cyclophosphamide and dactinomycin (BCD) given for 4-16 weeks prior to definitive surgery. Histologic examination of the resected primary tumor determined the effect of preoperative chemotherapy with many primary tumors showing greater than 90% tumor necrosis attributable to preoperative chemotherapy. All patients having this favorable effect of chemotherapy on the primary tumor were continued on the same chemotherapy regimen postoperatively (regimen B). However, in those patients not having a good effect of preoperative chemotherapy on the primary tumor, HDMTX with CFR was subsequently deleted from their postoperative chemotherapy and they were placed on a regimen containing cisplatinum at the dose of 120mg/M2 with mannitol diuresis combined with Adriamycin in addition to BCD (regimen A). In the current study, 35 of the 57 patients did not demonstrate a good effect of chemotherapy on the primary tumor and were assigned to regimen A postoperatively. Of these 35 patients, 32 (91%) have remained continuously free of recurrent or metastatic disease from 6-34 months following the start of therapy. Among the 22 remaining patients having a good histologic response and treated with regimen B postoperatively, there has been only one relapse in a patient who had a local recurrence in the area of an inadequately resected primary tumor three months after the cessation of chemotherapy. Thus, 53 of 57 patients (93%) are continuously with no evidence of recurrent or metastatic disease from 6-35 months (median, 20 months) from the start of treatment. This study demonstrates the value of thorough histologic examination in predicting survival in responding patients and in helping identify patients whose disease-free survival rate can be substantially increased if they are given alternative postoperative adjuvant chemotherapy after failing to have a good response to preoperative chemotherapy. This individualized chemotherapeutic strategy has yielded the highest disease-free survival rate reported to date for osteogenic sarcoma.

Antineoplastic Agents↗

PubMed1982

Chemotherapy of a malignant, metastasizing giant-cell tumor of bone: report of an unusual case and the response to combination chemotherapy.

A 13-year-old girl was treated surgically for a giant-cell tumor of bone originating in the talus and for a recurrence in the distal tibia. She later developed liver and lung metastases and was treated for two years, five months with a combination of vincristine, doxorubicin, cyclophosphamide and actinomycin-D, and thereafter with high-dose methotrexate/vincristine with citrovorum factor rescue. A good response was obtained and the patient is without evidence of disease 12 months after a salvage thoracotomy for residual disease in the left lung. Aspects of this singular case are discussed.

Adolescent↗

PubMed1982

Treatment for meningeal carcinomatosis in breast cancer.

Forty breast cancer patients with meningeal carcinomatosis were treated with a combined program of whole brain irradiation therapy with intrathecal and intraventricular methotrexate and citrovorum factor rescue. Responses were seen in 26 patients (65%); 13 patients (35%) failed to respond. The median survival time for the responding patients was six months, and for the nonresponders, one month. Factors affecting response and survival included pretreatment spinal fluid glucose, protein, and duration of CNS-related symptomatology prior to onset of therapy. In contrast, pretreatment CSF tumor cell count, CEA and initial CNS functional status did not appear to have prognostic significance. The authors conclude that following intensive therapy there can be much improvement in the quality of life and disease-free survival in breast cancer patients with meningeal carcinomatosis.

Brain↗

PubMed1982

Combination chemotherapy of advanced sarcomas in adults with "CYOMAD" (S7).

Response rates of metastatic soft part sarcomas to chemotherapy have varied from 27 and 44% for our ALOMAD and OMAD protocols to 46-55% reported for CYVADIC. The present combination, CYOMAD, consists of the induction part of ALOMAD (vincristine, high-dose methotrexate with citrovorum factor rescue, Adriamycin and DTIC) alternating with a condensed version of CYVADIC (cyclophosphamide, vincristine, adriamycin and DTIC). Forty-one patients with advanced soft-part sarcomas were entered on the CYOMAD program of whom 36 were considered evaluable. Complete responses (CR) were seen in four patients had partial (PR) in five patients for a major response rate of 25%. Responders had an overall longer survival than nonresponders (20 versus 13 months). Toxicity was substantial with both gastrointestinal side effects and myelosupression common. Possible Adriamycin cardiotoxicity was noted in four patients. Cyomad offered no therapeutic advantage over previous protocols and was even less well tolerated than some.

Adolescent↗

PubMed1983

Adjuvant chemotherapy of malignant fibrous histiocytoma of bone.

Malignant fibrous histiocytoma (MFH) is a pleomorphic sarcoma that is uncommon in children. It most frequently arises from the soft tissues; however, it has been recently established that primary bone MFH also exists. Surgical resection or amputation is the cornerstone of treatment for MFH of bone. But, with this modality of therapy alone the majority of patients develop either distant metastases or local recurrence. This study reports on three adolescent girls with MFH of bone who were successfully treated with radical resection and 18 months of adjuvant chemotherapy with vincristine, high dose methotrexate, Citrovorum Factor rescue, and Adriamycin. All three patients remain disease-free for a follow-up period of 42-48 months. The current regimen was well tolerated. Morbidity was minimal, with no patient developing any significant drug-related complications. The adjuvant chemotherapy regimen described appears to be effective in prolonging survival in patients with MFH of bone and appears to warrant further study in additional patients.

Adolescent↗

PubMed1983

Chemotherapy of malignant fibrous histiocytoma of bone. A report of five cases.

Five patients with evaluable malignant fibrous histiocytoma (MFH) of bone (three with primary tumor and two with primary tumor and metastatic disease) were treated with preoperative chemotherapy including high dose methotrexate (HDMTX) with citrovorum factor rescue (CFR) as is used for patients with osteogenic sarcoma. All five patients demonstrated a clinical response to chemotherapy. Three of four patients who underwent surgery had complete responses and one patient had greater than 90% tumor necrosis as documented by histologic examination of the resected primary tumor. All four patients who underwent surgery following preoperative chemotherapy are surviving free of disease from one to six years from the start of treatment; chemotherapy was discontinued after six to 11 months in these patients. The median disease-free survival time is 31.5 months. This study demonstrates the effectiveness of chemotherapy in MFH of bone, and in particular the effectiveness of HDMTX with CFR which caused measurable responses in all patients while receiving this therapy as a single agent.

Adolescent↗

PubMed1983

Evaluation of levamisole as an adjuvant to chemotherapy for treatment of ANLL.

Levamisole is a synthetic, orally administered, relatively nontoxic compound with immunorestorative ability. Levamisole was tested in this study of 60 adults with acute nonlymphocytic leukemia (ANLL) to determine if augmentation of response rate or duration, or survival over that obtained with a standard chemotherapy regimen alone would result. The chemotherapy regimens for all patients consisted of daunorubicin and cytosine arabinoside for induction and consolidation, methotrexate with citrovorum factor reversal in a cytoreductive phase, and late intensification with thioguanine and cytosine arabinoside. The first 30 patients received chemotherapy alone; a second group of 30 patients were scheduled to receive levamisole in addition to chemotherapy. Levamisole, 45 mg/m2, was administered orally twice daily for three consecutive days each week beginning one week after the initiation of induction chemotherapy and continuing until relapse. No significant difference emerged between the two groups with respect to remission rate, time to achieve remission, postrelapse survival, or total survival. However, a trend towards improved postcomplete remission survival (P = 0.072) was noted in the levamisole group, and patients who received levamisole had a significantly greater reinduction rate after relapse (P = 0.019).

Adult↗

PubMed1985

Control of primary osteosarcoma with chemotherapy.

High-dose methotrexate with citrovorum factor "rescue" (MTX-CF) produced an apparent complete response of the primary tumor in three patients with osteosarcoma. The response was sustained with MTX-CF, intra-arterial cis-diamminedichloroplatinum II (CDP) and Adriamycin (doxorubicin) for 18 months. Treatment was then electively discontinued. Local recurrence occurred in two patients, 6 and 4 months later, respectively. MTX-CF was reinstated and a complete response was again achieved in one patient. This has been maintained for 15+ months with MTX-CF and intra-arterial CDP administered for 13 of the 15+ months. Reinduction with MTX-CF failed in the second relapsed patient but an apparent remission was again achieved with radiation and intra-arterial CDP. This has been maintained with intravenous CDP, cyclophosphamide and phenylalanine mustard for 14+ months. A complete response in the primary tumor was still present in the nonrelapsed patient, 42 months from diagnosis. All patients have remained free of pulmonary metastases, 40+ to 42+ months from diagnosis.

Adolescent↗

PubMed1985

Transient neurologic disturbances induced by high-dose methotrexate treatment.

Temporary neurologic abnormalities were detected in 9 of 60 patients undergoing treatment with high-dose methotrexate and citrovorum factor rescue (MTX-CF) for osteosarcoma. The incidence of abnormalities and abnormalities themselves were more severe than previously reported. This was attributed to an increased dose and more frequent administration of MTX-CF. In view of the transient nature of the abnormalities, a biochemical cause is implicated, and the mechanisms by which it may occur are discussed.

Bone Neoplasms↗