Recognition of nucleoside triphosphates during RNA-catalyzed primer extension

In support of the idea that certain RNA molecules might be able to catalyze RNA replication, a ribozyme was previously generated that synthesizes short segments of RNA in a reaction modeled after that of proteinaceous RNA polymerases. Here, we describe substrate recognition by this polymerase ribozyme. Altering base or sugar moieties of the nucleoside triphosphate only moderately affects its utilization, provided that the alterations do not disrupt Watson-Crick pairing to the template. Correctly paired nucleotides have both a lower K(m) and a higher k(cat), suggesting that differential binding and orientation each play roles in discriminating matched from mismatched nucleotides. Binding of the pyrophosphate leaving group appears weak, as evidenced by a very inefficient pyrophosphate-exchange reaction, the reverse of the primer-extension reaction. Indeed, substitutions at the gamma-phosphate can be tolerated, although poorly. Thio substitutions of oxygen atoms at the reactive phosphate exert effects similar to those seen with cellular polymerases, leaving open the possibility of an active site analogous to those of protein enzymes. The polymerase ribozyme, derived from an efficient RNA ligase ribozyme, can achieve the very fast k(cat) of the parent ribozyme when the substrate of the polymerase (GTP) is replaced by an extended substrate (pppGGA), in which the GA dinucleotide extension corresponds to the second and third nucleotides of the ligase. This suggests that the GA dinucleotide, which had been deleted when converting the ligase into a polymerase, plays an important role in orienting the 5'-terminal nucleoside. Polymerase constructs that restore this missing orientation function should achieve much more efficient and perhaps more accurate RNA polymerization.

Single agent paclitaxel as a first-line therapy in advanced urothelial carcinoma: its efficacy and safety in patients even with pretreatment renal insufficiency

BACKGROUND

Cisplatin-based chemotherapy is the mainstay of the treatment for advanced urothelial cancer, but patients with renal insufficiency before therapy are usually contraindicated to receiving platinum-based chemotherapy. Paclitaxel is one of the most promising agents against advanced urothelial carcinoma in recent trials and it can be easily tolerated even in patients with compromised renal function. We conducted a study in order to evaluate the efficacy and safety of paclitaxel as a first-line therapy in advanced urothelial carcinoma patients.

METHODS

Thirteen advanced chemo-naive urothelial carcinoma patients with a median age of 71 years were studied, seven of them demonstrating renal insufficiency (pretreatment serum creatinine > or = 1.5 mg/dl). All 13 patients received a minimum of two cycles of paclitaxel 175 mg/m2, delivered by intravenous infusion for 3 h every 3 weeks.

RESULTS

Four of the 13 patients responded to treatment, a response rate of 30.8%, with two of these achieving complete remission and two showing partial responses. The median overall survival period of all 13 patients was nine months (95% Cl: 6.51-11.49) and our study revealed a statistical tendency in the difference of median overall survival time between responders and non-responders (13 months versus 7.5 months, log-rank p = 0.038), although the number of cases was limited. The differences in response rate and median overall survival time, comparing patients with renal insufficiency and those with normal renal function, were not significant. Treatment-related toxicity was mild, with only two (15.4%) patients suffering from grade 3-4 leukopenia. No treatment-related mortality was noted.

CONCLUSIONS

Single-agent paclitaxel can be used as a first-line therapy in advanced urothelial carcinoma patients, and is especially suitable for those with pretreatment renal insufficiency, since the antitumor activity is significant while toxicity is well tolerated.

Randomized trial comparing weekly bolus 5-fluorouracil plus leucovorin versus monthly 5-day 5-fluorouracil plus leucovorin in metastatic colorectal cancer

BACKGROUND/AIMS

The purpose of this study was to compare the efficacy and toxicity profiles of weekly intravenous (i.v.) bolus injection of 5-fluorouracil plus low-dose leucovorin with the Mayo Clinics' monthly 5-day schedule of 5-fluorouracil and leucovorin in the treatment of metastatic colorectal cancer.

METHODOLOGY

A total of 96 patients with previously untreated metastatic colorectal cancer were randomized to receive either a weekly i.v. bolus injection of 5-fluorouracil 400 mg/m2 plus leucovorin 20 mg/m2 (weekly arm), or i.v. bolus injection of 5-fluorouracil 425 mg/m2 plus leucovorin 20 mg/m2 for 5 consecutive days every 4 or 5 weeks (monthly arm). Therapy was continued until disease progression or unacceptable toxicity appeared. In the presence of disease progression, the study regimen was stopped and second-line treatment was instituted after the patient was discontinued from this study.

RESULTS

There was no significant difference of response rates between both regimens. The response rate were 14.3% in the weekly arm (2 CR and 5 PR, 95% CI: 2.6-25.2%) and 10.6% in the monthly arm (1 CR and 4 PR; 95% CI: 6.5-32.3%), respectively (P = 0.8957). The survival times were also similar between the two (P = 0.4207, log-rank test). The median survival were 15.8 months in the monthly arm and 18.4 months in the weekly arm. Hematologic toxicity was minimal in both arms. However, the monthly arm produced a higher toxicity in severe (grade 3-4) diarrhea (14.9% vs. 2%; P = 0.029) and stomatitis (8.5% vs. 0; P = 0.054).

CONCLUSIONS

Weekly bolus injection of 5-fluorouracil and low-dose leucovorin achieved a similar response rate and survival as compared with the Mayo Clinics' monthly 5-day schedule, but severe toxicity was less commonly seen using the weekly regimen. As current chemotherapeutic treatment for metastatic colorectal cancer is largely palliative rather than curative, the weekly bolus regimen may be a more favorable approach in managing metastatic colorectal cancer.

Phase II study of oral tegafur-uracil and folinic acid as first-line therapy for metastatic colorectal cancer: Taiwan experience

BACKGROUND

Tegafur-uracil has become an important regimen in the treatment of metastatic colorectal cancer. Tegafur is a prodrug that is converted to 5-fluorouracil (5-FU) and has been reported to be less toxic and to have a higher therapeutic index. The additional advantage of tegafur is oral administration, an important consideration to improve the quality of life in these patients. Tegafur in combination with uracil is thought to have greater anti-tumor activity due to the inhibitory effect of uracil on the degradation of 5-FU by hepatic dihydropyrimidine dehydrogenase. Tegafur with folinic acid has been reported with modest efficacy and acceptable toxicity. The purpose of this study was to evaluate the effectiveness and toxicity profile of oral tegafur-uracil plus folinic acid in Chinese patients with metastatic colorectal cancer.

METHODS

Between May 1998 and August 1999, 40 patients with metastatic colorectal carcinoma were enrolled in this study. All the patients had to have measurable lesions. The initial dose of tegafur-uracil was 300 mg/m2/day for 28 days, followed by a 7-day rest period. Folinic acid was administered orally at a dose of 60 mg/day concurrently with tegafur-uracil. For patients with neutrophil count <1500/microl or a platelet count <100,000/microl after treatment, the treatment was postponed for a maximum of 2 weeks. After that time, if the neutrophil count was 1000-1500/microl and the platelet count was 70,000-100,000 microl, the dose of tegafur-uracil was reduced by 50%, and if lower values resulted, the treatment was discontinued.

RESULTS

Forty patients received a total of 318 courses of treatment and a response rate of 32.5% (95% CI, 18-47%), including five complete remissions and eight partial remissions, was achieved. Toxicity was mild and generally tolerable. Gastrointestinal toxicities, including diarrhea, nausea and vomiting, were the major side effects. Seven incidences (17.5%) of grade 3-4 gastrointestinal toxicity were observed. Hematological toxicities were minimal with no evidence of severe (grade 3 or 4) leukopenia and thrombocytopenia. No episode of hepatic, renal, cardiac or neurological toxicity occurred. Two patients (5%) developed transient painful fissuring erythroderma over their palms and soles (the hand-foot syndrome).

CONCLUSIONS

The data from our study indicate that oral tegafur-uracil plus folinic acid is an active and tolerable first-line treatment for Chinese patients with metastatic colorectal cancer, with the additional advantage of being easily administered at home.

Vincristine-induced dysphagia suggesting esophageal motor dysfunction: a case report

Transient esophageal motor dysfunction with dysphagia was observed in a 62-year-old man receiving vincristine-containing chemotherapy for non-Hodgkin's lymphoma. Neurological examinations, including muscle strength of extremities, deep tendon reflexes and cranial nerves, were normal. However, the patient complained of severe numbness in the fingertips and toes. The results of esophagogram and esophagoscopy were unremarkable. However, a significantly prolonged esophageal transit time was observed. Vincristine was considered as the causative agent. Empirical vitamin and metoclopramide were prescribed for his neurological symptoms but there was no improvement. The symptoms of dysphagia subsided spontaneously 2 weeks later. However, prompt recurrence of severe dysphagia was observed again after administration of the second and third courses of treatment, which again disappeared upon discontinuation of the drug. Peripheral nerves and the gastrointestinal tract are often affected by vincristine. Common gastrointestinal tract symptoms of vincristine neuropathy may be colicky abdominal pain and constipation. However, vincristine-induced esophageal motor dysfunction with dysphagia is uncommon but generally reversible. The oncologist and chemotherapist should be aware of this complication.

Factors predictive of survival in patients with node-positive colorectal cancer in Taiwan

BACKGROUND/AIMS

Preoperative CEA levels, depth of tumor penetration, and the number of positive lymph nodes were reported as independent factors prognostic of survival in colorectal cancer patients. This study was carried out in an effort to evaluate the prognostic significance of these three factors in patients with Dukes' C colorectal cancer in Taiwan.

METHODOLOGY

Between 1992 and 1994, a total of 112 patients with node-positive colorectal cancer were evaluated retrospectively at the Veteran General Hospital-Taipei. All patients underwent potentially curative surgery and received 5-fluorouracil based adjuvant chemotherapy. Reference to the Dukes' classification was according to the classical criteria described in 1932 for carcinoma of the rectum and adapted for use in colonic tumors. Data on the location of the tumor, depth of penetration, number of positive lymph nodes, degree of tumor differentiation, and preoperative CEA levels were analyzed to understand their association with survival. Blood samples for CEA measurement were taken a few days before operation. A multivariate analysis using the Cox's proportional hazards regression model was then performed to determine the most important independent predictors of survival among all the possible variables.

RESULTS

Using univariate analysis the number of positive lymph nodes (P < 0.001), penetration of the bowel wall (P < 0.001), and preoperative CEA levels (P < 0.001) were found as significant prognostic factors, while the degree of tumor differentiation, location of the tumor, age and sex were not significant. Using multivariate Cox analysis the number of positive lymph nodes, penetration of the bowel wall, and preoperative CEA levels were still found as independent prognostic factors in node-positive colorectal cancer patients.

CONCLUSIONS

Data obtained from our study indicates that preoperative CEA levels, depth of tumor penetration, and the number of positive lymph nodes were independent prognostic factors in Dukes' C colorectal cancer patients. They could serve as appropriate modifications of the initial Dukes scheme in node-positive diseases.

Lack of mutations of BCL6 and BCL10 genes in mucosa-associated lymphoid tissue lymphomas of the orbital adnexa

Knowledge regarding the molecular pathogenesis and progression of mucosa-associated lymphoid tissue (MALT) lymphomas of ocular adnexa is limited. Eleven cases of ocular MALT lymphoma were analyzed by clonal rearrangement of antigen receptor genes using Southern blot hybridization. Polymerase chain reaction-single stranded conformational polymorphism analysis and DNA sequencing was utilized to analyze the mutations of BCL6 and BCL10 genes. Clonal rearrangement of immunoglobulin heavy genes was found in all 11 patients. No point mutation was found in BCL6 or BCL10 genes in any of the samples analyzed. We suggest that mutations of BCL6 and BCL10 genes are rare in low-grade MALT lymphoma of ocular adnexa and are unlikely to be involved in the pathogenesis of the disease. But the role of alterations of both BCL6 and BCL10 genes in the disease progression of low-grade MALT lymphoma require additional study.

Immunophenotypic and genotypic characteristics of chronic myelogenous leukemia in blast crisis

BACKGROUND

Chronic myelogenous leukemia (CML) may transform into blast crisis (BC) if not properly treated. Among patients with transformation, 20% to 30% will develop BC with lymphoid-associated antigens (Ly-BC), and the remaining cases with myeloid-associated antigens (My-BC) or with both (Mix-BC). In this study, we investigated the lineage of blast cells in CML-BC using immunophenotypic and genetic analyses and analyzed the prognostic significance of genotypic change in CML-BC.

METHODS

Twenty-one patients with CML-BC diagnosed at the Taipei Veterans General Hospital from 1982 to 1992 were included. Immunophenotyping was done by using the avidin-biotin immunoperoxidase technique. Genetic analyses were carried out by using Southern Blot hybridization. The prognostic influence of genotypic change was analyzed.

RESULTS

Thirteen patients (61.9%) expressed myeloid-associated antigens, one patient (4.8%) expressed megakaryoblast-associated antigens, four patients (19%) expressed B lymphoid-associated antigens and three patients (14.3%) expressed both myeloid and B lymphoid antigens. Clonal rearrangement of the immunoglobulin heavy chain (IgH) gene was found in six cases. Among them, four expressed B lymphoid markers only and two expressed both myeloid and B lymphoid markers. Patients with clonal IgH gene rearrangement tended to have a better response to chemotherapy (50% vs 8.3%, p = 0.08) and significantly longer survival (median survival, 5 months vs 3 months, p < 0.05) than did those with a germline configuration.

CONCLUSIONS

Clonal rearrangement of the IgH gene was found mostly in cases of Ly-BC and Mix-BC. We found that CML-BC with clonal rearrangement of the IgH gene had a more favorable prognosis than in cases with a germline configuration.

Comparison of the efficacy and safety of oral granisetron plus dexamethasone with intravenous ondansetron plus dexamethasone to control nausea and vomiting induced by moderate/severe emetogenic chemotherapy

BACKGROUND

Chemotherapy-induced nausea and vomiting can affect cancer patients' compliance with cytotoxic chemotherapy. Currently, there are some new antiemetic therapies for the treatment of chemotherapy-induced emesis. A single institution, randomized, open, parallel trial was done to compare oral granisetron plus intravenous (i.v.) dexamethasone with intravenous ondansetron for the prevention of moderate or severe emetogenic chemotherapy-induced acute and delayed emesis.

METHODS

Fifty-one cancer patients were treated with moderate/severe emetogenic chemotherapy and randomized to receive either oral granisetron 1 mg twice daily or i.v. ondansetron 8 mg every 8 hours combined with i.v. dexamethasone 10 mg on the day of chemotherapy. The efficacy and safety of the two antiemetic regimens were compared.

RESULTS

Oral granisetron plus i.v. dexamethasone had comparable antiemetic efficacy for the prevention of nausea in the first 24-hour period after initiation of chemotherapy compared with intravenous ondansetron plus i.v. dexamethasone. The complete response of antiemesis in the first 24-hour period after initiation of antiemetic therapy between granisetron and ondansetron were 84.0% (95% CI, 62.9%-95.6%) and 84.6 (95% CI, 64.0%-97.5%). The complete response for delayed emesis after initiation of antiemetic therapy between granisetron and ondansetron were 16.0% (95% CI, 4.5%-36.1%) and 19.2% (95% CI, 6.8%-40.7%0. There was diarrhea in 12% of patients receiving granisetron therapy and constipation in 23.1% of the ondansetron group.

CONCLUSIONS

Oral granisetron plus i.v. dexamethasone and i.v. ondansetron plus i.v. dexamethasone are potentially equally effective antiemetic agents in the prevention of moderate or severe emetogenic chemotherapy-induced acute or delayed emesis. Oral granisetron with dexamethasone appears to be a suitable alternative antiemetic agent in cancer patients who receive moderately or severely emetogenic chemotherapy.

Venous gangrene in a patient with adenocarcinoma of the lung

Cancer-related thromboembolism is a severe but not uncommon paraneoplastic syndrome in mucinous cancer patients. However, cancer-induced venous gangrene is extremely rare and has never been reported in the English literature. Here, we present a case of lung cancer complicated with venous gangrene of the left foot. An elevated serum anticardiolipin level was detected during hospitalization, but the patient's clinical condition stabilized after heparinization. We suggest that in cancer patients, an elevated serum anticardiolipin antibody level might be a warning sign of an impending thrombotic event and that low-molecular-weight heparin is a sensible choice in treating this kind of cancer-related thromboembolism.

Ruptured metastatic ovarian carcinoma presenting as acute abdomen

Acute abdomen is a challenge to first-line physicians because of frequently missed diagnoses and potential follow-on legal problems. Improving the management of these patients is of paramount importance, not only for saving lives, but also for reducing untoward problems associated with improper management. We present a case of a patient with acute abdomen due to intraperitoneal hemorrhage secondary to rupture of an ovarian tumor. Following emergency surgery, the patient was diagnosed with metastatic ovarian carcinoma. Because of improper preparation of the gastrointestinal tract, the patient underwent repeat exploratory laparotomy for colon carcinoma. Although this situation did not affect the outcome of the patient in this case, we are concerned that the patient did not benefit from a single operation, with primary complete excision of the tumor plus a colostomy. The outcome of patients with pelvic malignancy, especially those with ovarian carcinoma, might be better if initial surgery achieved optimal tumor debulking. This is possible with good preoperative planning and preparation. We emphasize the importance of preoperative preparation in spite of urgently needed care. Furthermore, every first-line physician should communicate the possibility of malignancy to patients and their families.

Preoperative carcinoembryonic antigen level as an independent prognostic factor in colorectal cancer: Taiwan experience

BACKGROUND

Preoperative carcinoembryonic antigen (CEA) level is considered as a factor predictive of survival in colorectal cancer patients. Patients with normal (<5 ng/ml) or lower preoperative CEA levels were reported to have significantly longer survival. This study was carried out in an effort to evaluate the prognostic significance of preoperative CEA levels of patients with colorectal cancer in Taiwan.

METHODS

Between 1990 and 1994, 218 patients with histologically confirmed colorectal cancers were evaluated retrospectively at the Veterans General Hospital-Taipei. All the patients had undergone potentially curative surgery. Patients with metastatic diseases were not included. 5-Fluorouracil-based adjuvant chemotherapy was administered if the patients had Dukes' C disease. Reference to the Dukes' classification was according to the classical criteria described in 1932 for carcinoma of the rectum and adapted for use in colonic tumors. Data on gender, age, degree of tumor differentiation, location of the tumor, tumor size, lymph node metastasis, penetration of the bowel wall and preoperative CEA levels were analyzed to determine their association with survival. Blood samples for CEA measurement were taken a few days before operation and were analyzed using the radioimmunoassay method. Multivariate analysis by Cox's proportional hazards regression model was performed to determine the most important predictors of survival among all of the possible variables.

RESULTS

By univariate analysis, the size of the tumor (p = 0.012), lymph node metastases (p = 0.007), penetration of the bowel wall (p < 0.001) and preoperative CEA levels (p < 0.001) were found to be significant prognostic factors, while gender, age, degree of tumor differentiation and location of the tumor were not significant. By multivariate Cox analysis, lymph node metastases (p = 0.003), penetration of the bowel wall (p = 0.0001) and preoperative CEA levels (p = 0.0001) were found to be independent prognostic factors in colorectal cancer patients.

CONCLUSIONS

The data from our study indicate that in addition to lymph node metastases and penetration of the bowel wall, the preoperative CEA levels are also an independent prognostic factor in non-metastatic colorectal cancer patients after curative surgery. This could serve as an appropriate modification to the initial Dukes' scheme in colorectal cancer.

Effect of oncostatin-M on proliferation and activity in osteoblastic MC3T3-E1 cells

BACKGROUND

Osteogenic cells (osteoprogenitor cells and osteoblasts) respond to specific cytokines, growth factors and hormones. Understanding which cytokines affect osteogenic cells and the consequences of those effects are central to understanding normal and pathologic bone remodeling. Oncostatin-M (OSM) is a glycoprotein interleukin-6 cytokine known to inhibit bone resorption in fetal long bone cultures. However, it is still unclear whether OSM affects bone formation. The aim of this study was to investigate the effects of OSM on bone formation (bone cell proliferation, differentiation and function).

METHODS

For the in vitro bone formation bioassay, MC3T3-E1 cells were plated into 35 mm Petri dishes and cultured in Dulbecco's modified eagle medium (DMEM). Various concentrations (1, 10, 100 or 1,000 units/ml) of OSM were added daily to the experimental dishes, while only DMEM was added in the control dishes during the proliferative and differentiated stages of MC3T3-E1 cell growth. The effect of OSM on bone formation was evaluated using 3H-thymidine incorporation, alkaline phosphatase expression, type I collagen synthesis assay and phase-contrast light microscopy.

RESULTS

OSM significantly decreased osteoprogenitor cell proliferation and alkaline phosphatase activity in a dose-related fashion. There was no effect on type I collagen synthesis noted at any OSM dose. Thus, OSM exerted significant inhibition on bone formation.

CONCLUSIONS

OSM is a potent inhibitor of bone formation by decreasing both osteoprogenitor cell proliferation and alkaline phosphatase activity.

Prognostic significance of immunoglobulin and T cell receptor gene rearrangements in patients with acute myeloid leukemia: Taiwan experience

We investigated the prognostic significance of lymphoid antigen receptor gene rearrangement in patients with newly diagnosed acute myeloid leukemia (AML). Thirty-nine patients were included in the study. Clonal gene rearrangement of immunoglobulin heavy chain (IgH) and T cell receptor beta chain (TCRbeta) was found in leukemic cells in 11 (28.2%) and 10 (25.6%) patients, respectively. Five (12.8%) had both IgH and TCRbeta gene rearrangements. Three of the seven (42.9%) B-lymphoid marker-positive and eight of the 32 (25%) B-lymphoid marker-negative patients had clonal IgH gene rearrangements. Five of the 11 (45.5%) T-lymphoid marker-positive and 5 of the 28 (17.9%) T-lymphoid marker-negative patients had clonal TCRbeta gene rearrangements. All patients were treated with similar regimens. The complete remission rate (62.5% vs 65.2%, p=1.000) and median survival (13 vs 14 months, p=0.366) were similar in patients with and without clonal IgH or TCRbeta gene rearrangements. In conclusion, while clonal rearrangements of IgH or TCRbeta genes were found in AML patients, they did not appear to effect the prognosis.

Fulminant hepatitis is significantly increased in hepatitis B carriers after allogeneic bone marrow transplantation

BACKGROUND

Bone marrow transplantation (BMT) is effective treatment for many hematologic disease, but performed in a population with a high endemic hepatitis B virus carrier rate, the incidence of liver function impairment and fulminant hepatitis (FH) is expected to be raised.

METHODS

Forty-three hepatitis B virus carriers received high-dose chemotherapy and BMT, 32 patients received an allogeneic graft, and 11 patients autologous marrow. Acute graft-versus-host disease prophylaxis consisted of methotrexate on day 1, 3, 6, and 11 and cyclosporine for 6 months.

RESULTS

After a median follow-up period of 68 months (range: 1-11.5 years), 26 (81.3%) allogeneic BMT patients developed impaired liver function (LF), 5 progressed to FH on day 93, 169, 170, 180, and 468, respectively, and died after an average of 13.8 days (range: 1-45 days). Whereas only 4 (36.4%) autologous BMT patients developed impaired LF, and none FH. Impaired LF (P=0.026, chi-square), and FH (odds ratio=12.86, P=0.009 for coefficient) were significantly related to an allogeneic marrow graft, and the timing of liver function impairment coincided with cyclosporine withdrawal. Hepatitis B surface antigen (HbsAg) disappeared from the serum in 4/14 (28.6%) patients receiving a marrow graft from an HbsAg+ donor. HbsAg was not detected in the serum after BMT in 2/11 (18.2%) autologous BMT patients.

CONCLUSIONS

Hepatitis B virus carriers receiving a marrow graft from an HbsAg+ donor have a significantly increased risk of FH.

p53 gene mutations and rearrangements in non-Hodgkin's lymphoma

BACKGROUND

Alterations of the p53 gene have been associated with the progression of certain human malignancies. To establish further the correlation between p53 gene alterations and progression of non-Hodgkin's lymphomas (NHLs), the authors analyzed both mutations and rearrangements of the p53 gene in a cohort of 84 NHLs.

METHODS

Eighty-four NHLs were analyzed for p53 gene alterations. Point mutations of exons 5-9 were studied by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP), and DNA rearrangements were studied by Southern blot analysis. RESULTS. Point mutations and DNA rearrangements of the p53 gene were detected in 6 (7.2%) and 3 (3.6%) patients, respectively. All p53 gene abnormalities were found exclusively in B-cell NHLs. Taken together, patients with p53 gene alterations had poorer survival than other patients (P = 0.024). However, of the three patients with p53 gene rearrangements, the two who appeared to have one normal allele showed a relatively better response to chemotherapy and had longer survival (27 and 47 months). In contrast, the remaining patient who had rearranged bands much stronger than the germline, and thus appeared to have both alleles rearranged, was refractory to chemotherapy and had poorer survival (6 months).

CONCLUSIONS

Patients with NHLs of intermediate and high grades who carried point mutations or rearrangements of p53 genes had worse outcomes than other patients. Patients with one abnormal p53 allele and one residual normal allele had a more favorable prognosis than those with two abnormal alleles.

ESHAP as salvage therapy for refractory non-Hodgkin's lymphoma: Taiwan experience

BACKGROUND

The ESHAP regimen, a combination of the chemotherapeutic drugs etoposide, methylprednisolone (solumedrol), high-dose cytarabine (ara-C) and cisplatin, has been shown to be active against refractory non-Hodgkin's lymphoma in therapeutic trials. We were interested in determining whether this regimen would be effective and tolerable for Chinese patients.

METHODS

Thirty-two patients with refractory/relapsed non-Hodgkins lymphoma (23 intermediate-grade and nine high-grade) were enrolled in this study. Etoposide was administered at a dose of 40 mg/m2/day as a 1 h intravenous infusion from day 1 to day 4, solumedrol 500 mg/day was given as a 15 min intravenous infusion from day 1 to day 5, ara-C 2 g/m2 was given as a 2 h intravenous infusion on day 5 and cisplatin was given at a dose of 25 mg/m2/day as a continuous infusion from day 1 to day 4. Clinical efficacy and toxicity were assessed on the basis of the WHO criteria.

RESULTS

Ten patients (31.3%, 95% Cl 15.2-47.4%) attained complete remission (CR) and seven had partial remission (PR). The overall response rate was 53.1% (95% Cl 35.8-70.4%). In eight of the 10 CR patients, the remission lasted for more than 8 months. The remaining two patients had CR of 5 and 6 months. The median duration of CR was 12.2 months (range 5-22 months). Myelosuppression with subsequent infections was the major toxicity. Severe leukopenia (WBC < 1000/microliter) lasted for an average of 12 days and thrombocytopenia (< 25,000/microliter) 18 days. One patient (3.1%) died of neutropenia-associated sepsis within 4 weeks after treatment. Non-myeloid toxicities included alopecia in 66% (28% grade 2, 22% grade 3), stomatitis in 72% (25% grade 2, 28% grade 3, 13% grade 4), hepatotoxicity in 9% (3% grade 2), renal toxicity in 13% (6% grade 2, 3% grade 3) and infection in 56% (18% grade 2, 25% grade 3, 13% grade 4). The majority of the responders relapsed within 2 years after ESHAP treatment. Median survival for all patients was 8.6 months.

CONCLUSIONS

ESHAP is an active and tolerable regimen in Chinese patients with relapsed/refractory lymphoma, but the duration of remission is brief and without significant impact on survival.

Toxic cardiogenic shock in a patient receiving weekly 24-h infusion of high-dose 5-fluorouracil and leucovorin

A 54-year-old man was treated with weekly 24-h infusion of high-dose 5-fluorouracil (2600 mg/m2) and leucovorin (100 mg/m2) for metastatic colon cancer. At first, he tolerated the treatment well and no significant toxicity was identified. After a total of eight courses of treatment, a stable disease was observed, but mild shortness of breath was found on occasion. The patient had no previous history of cardiac disease and the heart performance assessed by left ventricular ejection fraction before treatment was normal. Unfortunately, acute pulmonary edema with lethal cardiogenic shock occurred during the ninth course of treatment, in spite of intensive medical treatment. The chest X-ray showed extreme cardiomegaly. Repeated assessment of his heart function by echocardiogram and ventricular ejection fraction revealed a very poor cardiac performance. Toxic cardiogenic shock during weekly 24-h infusion of high-dose 5-fluorouracil and leucovorin is extremely rare. To the best of our knowledge, no case has been reported in the English literature. We report a case and the relevant literature about the incidence, clinical picture and possible pathophysiology on 5-fluorouracil-related cardioxicity is reviewed.

Phase II study of the modified regimen of etoposide, leucovorin and 5-fluorouracil for patients with advanced gastric cancer

BACKGROUND

The efficacy of the treatment of advanced gastric cancer is not very good. The response rate to the original etoposide--leucovorin--5-fluorouracil (ELF) treatment is 53% with tolerable side effects. Whether increasing the dose intensity by prolonging the duration of infusion with 5-fluorouracil (5-FU) and leucovorin (LV) from 3 to 5 days for advanced or metastatic gastric cancer patients would enhance the efficacy but not increase side effects is still unknown.

METHODS

Thirty-six advanced or metastatic gastric cancer and chemotherapy-naïve patients with measurable or evaluable diseases were scheduled to receive intravenous etoposide 100 mg/m2/day on days 2-4, LV 300 mg/m2/day intravenously and 5-FU 500 mg/m2/day intravenously on days 1-5, every 4 weeks. All patients who received at least two courses of chemotherapy were evaluated for tumor response, survival and response duration and toxicity according to the WHO criteria.

RESULTS

Thirteen patients showed a response, including five with complete response (CR). The overall response rate was 36% (95% confidence interval, CI, 20-52%) in the whole group and 46% (95% CI 28-66%) in the 28 patients with measurable disease. The median progression-free interval and overall median survival time were 5 and 7 months, respectively. The most frequent toxicity was alopecia (grade I/II 56.3%). The incidence of grade III or greater myelosuppression was 5.9%. No treatment-related death occurred.

CONCLUSIONS

The efficacy of the modified ELF by increasing the dosages of 5-FU and LV is not superior to the results of the original regimen, yet it is a relatively safe and tolerable combination regimen for advanced gastric cancer.

Navoban (tropisetron, ICS 205-930) and dexamethasone combination in the prevention of vomiting for patients receiving preconditioning high-dose chemotherapy before marrow transplantation

The anti-emetic efficacy of a combination of tropisetron and dexamethasone was studied in 33 patients who underwent bone marrow transplantation. Another 50 patients receiving conventional anti-emetic therapies in bone marrow transplantation served as control. On the first and second days of preconditioning chemotherapy, 51% and 36% respectively of patients in the tropisetron and dexamethasone group did not experience vomiting, compared with only 12% and 10% of control group patients (P < 0.001). The mean number of episodes of vomiting in the tropisetron and dexamethasone group was also significantly lower than in the control group (0.97+/-1.65 vs 3.50+/-2.45 and 1.30+/-1.40 vs 4.44+/-2.91 respectively, both P < 0.001). Control of vomiting in the two groups was not significantly different during days 3-6. Analysis of patients receiving busulfan and cyclophosphamide as the preconditioning regimen still showed better anti-emetic control in the tropisetron and dexamethasone group than in the control group on the first two days of treatment (total control rate 33.3% vs 6.5% and 44.4% vs 12.9% respectively, P < 0.001). Patients given tropisetron and dexamethasone combination more frequently suffered from dizziness and burning sensation of the chest. However, diarrhea and extrapyramidal symptoms were the most frequent adverse effects seen after using conventional anti-emetic combination. The combination of tropisetron and dexamethasone was thus superior to conventional anti-emetic combinations in preventing vomiting during preconditioning period of bone marrow transplantation. The adverse effects of this combination were minimal and well tolerated by patients.

Successful pregnancy following very high-dose total body irradiation (1575 cGy) and bone marrow transplantation in a woman with acute myeloid leukemia

A 22-year-old woman had a normal full-term delivery 6 years after a successful allogeneic bone marrow transplantation (BMT) for acute myeloid leukemia (AML). Conditioning therapy consisted of cyclophosphamide (120 mg/kg) and total body irradiation (TBI) to a total of 1575 cGy in seven fractions (225 cGy x 7, at a dose rate of 3.5 cGy/min). Graft-versus-host disease prophylaxis was with methotrexate and cyclosporin A. Grade I acute GVHD developed after BMT but there was no chronic GVHD. She became amenorrhoeic after BMT and serial gonadal testing indicated hypergonadotrophic hypogonadism. She became pregnant and delivered a full-term, healthy baby 6 years after BMT. Successful pregnancy after TBI of more than 1200 cGy is extremely rare. This case, to the best of our knowledge, is the second patient who received a higher dose of TBI (1575 cGy) to have a successful pregnancy. This and previous reports indicate that normal pregnancy is possible after BMT with TBI in excess of 1200 cGy.

Weekly 24-hour infusion of high-dose 5-fluorouracil and leucovorin in patients with advanced colorectal cancer: Taiwan experience

Between January 1994 and November 1995, 41 patients with metastatic colorectal carcinoma were enrolled in this study. All these patients had recurrent disease after a prior 5-fluorouracil based adjuvant chemotherapy or failed to achieve response by prior chemotherapy that included 5-fluorouracil. 5-Fluorouracil, 2600 mg/m2, was administered concurrently with 100 mg/m2 leucovorin over 24 hours of continuous intravenous infusion. The treatment was repeated every week until progressive disease was documented. Forty-one patients received a total of 810 courses of treatment. The overall response rate was 17.1% (95% confidence interval 5.6-28.6%). In two patients who achieved complete response, the liver was the metastatic site. The median survival was 18.4 months for responders and 12.6 months for non-responders. Gastrointestinal toxicities including diarrhea, stomatitis, nausea and vomiting were the major side-effects. Sixteen incidences (39.0%) of grade 2-3 gastrointestinal toxicities were observed. One patient (2.4%) developed a grade 3 cardiac toxicity, and another one (2.4%) had a grade 2 neurotoxicity. Hematological toxicities were minimal with no evidence of severe (grade 2 or more) leukopenia or thrombocytopenia. We conclude that in patients with pretreated metastatic colorectal cancer, weekly 24-hour infusion of high-dose 5-fluorouracil and leucovorin is associated with higher efficacy and tolerable toxicity. This regimen is a good option as a second-line treatment for those whose diseases are recurrent from or refractory to prior 5-fluorouracil, and deserves a longer period of follow-up.

Lethal acute pulmonary edema following intravenous naloxone in a patient received unrelated bone marrow transplantation

A 39-year-old man was diagnosed as having acute myeloid leukemia and received 6 courses of chemotherapy. The bone marrow revealed complete remission. He had no prior history of cardiac or pulmonary disease. HLA-matched unrelated bone marrow transplantation (BMT) was performed in September 1995. Pre-transplant studies including chest X-ray, electrocardiogram and pulmonary function test were normal. The procedure of BMT was smooth and serial bone marrow examination showed successful engraftment. Serial chest X-rays done every week after BMT were normal. There were no evidence of fluid overload but severe mucositis was noted. On the 38th day after BMT, intravenous injection of 10 mg morphine was prescribed to relief severe oral pain. Respiratory depression developed right after, and naloxone 0.4 mg was given by an intravenous route. One hour later, severe shortness of breath was noted and the emergent chest X-ray revealed acute pulmonary edema. He became unconscious 2 hours later and expired 24 hours after naloxone injection in spite of intensive medical treatment. Naloxone-induced acute pulmonary edema is an extremely rare but lethal complication. Only a few cases have been reported in English literature. We report a case of acute myeloid leukemia receiving unrelated BMT to develop acute pulmonary edema rapidly after intravenous injection of naloxone. The clinical features and pathogenesis are discussed.

Treatment of previously treated metastatic breast cancer by mitoxantrone and 48-hour continuous infusion of high-dose 5-FU and leucovorin (MFL): low palliative benefit and high treatment-related toxicity

For previously treated advanced breast cancer, there is no standard second-line therapy. Combination chemotherapy with mitoxantrone, high-dose 5-fluorouracil (5-FU) and leucovorin (MFL regimen) had been reported as an effective and well tolerated regimen. From October 1993 to November 1995, we treated 13 patients with previously chemotherapy-treated metastatic breast cancer by mitoxantrone, 12 mg/m2, on day 1 and continuous infusion of 5-FU, 3000 mg/m2, together with leucovorin, 300 mg/m2, for 48 h from day 1 to 2. Each course of chemotherapy was given every 4 weeks. Most of these patients had more than two metastatic sites, with lung metastasis predominant. Seven patients had been treated with anthracycline. Seven patients had previously received radiotherapy and seven had received hormone therapy. Median number of courses of MFL regimen given was six and the median cumulative dose of mitoxantrone was 68.35 mg/m2. One patient had complete response, seven had stable disease, none had partial response and five had progressive disease. The overall objective response rate was 7.6%. The median follow-up period was 14 months. Median survival was 16 months. Median progression-free survival was 5 months. A complete responder had relapse-free survival up to 17 months. Major toxicities were cardiotoxicity and leukopenia. Eight patients were dead in the last follow-up; two of them died of treatment-related toxicity. The MFL regimen achieves little palliative benefit and induces severe toxicity at a fairly high rate. Administration of this regimen to breast cancer patients who have been treated by chemotherapy and those with impaired heart function requires careful attention.

Augmentation of protein kinase C activity and liver cell proliferation in lead nitrate-treated rats

It is shown that lead alters calcium mediated cellular processes in several biological systems. Calcium enhances the activity of protein kinase C (PKC) which takes part in eliciting cell mitosis. In this study, the effects of lead nitrate on the activity of PKC enzyme were investigated in rat liver. The PKC activity was determined at 12, 24, 48, 72, 120, 168 hours after treatment with a single dose of lead nitrate in male Wistar rats. The results showed that the specific PKC activity of the purified particulate fraction was increased and reached a maximum at 24 hour, and lasted for 48 hours. This augmented activity of PKC was parallel with the increase of the lead level in the purified particulate fraction, although the protein levels of PKC alpha, PKC delta and PKC zeta were unchanged. Moreover, the frequency of mitotic cells also exhibited a significant increase, and like PKC activity, reached its maximum at 24 hour with accompany signs of liver enlargement. The results suggest that the PKC activation may be involved in promoting liver cell proliferation in lead nitrate-treated rats.