Tuberculous Skeletal Muscle Involvement in Acute Leukemia: Report on Two Cases

Bacterial infection of skeletal muscle (pyomyositis) is usually followed by abscess formation. The most commonly isolated pathogen is Staphylococcus aureus. Tuberculosis rarely affects patients with acute leukemia. The authors report on 2 patients, one with acute myelogenous leukemia and the other with acute lymphoblastic leukemia whose clinical course was complicated by tuberculous skeletal muscle abscesses. In both instances, musculoskeletal pain was accompanied by evidence of muscle abscesses by imaging studies of the painful areas. Therefore, in patients with acute leukemia and evidence of muscle abscesses with initial cultures negative for bacteria and fungi, one should include tuberculosis in the differential diagnosis.

Doctor, how long?

This study aimed to quantify the average survival time of cancer patients once terminal sedation was started until death and identify potential variables that may influence their survival time on sedation. This is a retrospective cohort analysis of all consecutive terminal cancer patients who died after starting terminal sedation at public tertiary Brazilian Hospital. A total of 532 cancer patients died in Hospital Estadual Mário Covas during this period and 181 out of them who received terminal sedation were included in this analysis. The median survival was 27 h. By multivariate analysis, increase in the dose of sedative drug during sedation (odds ratio 1.576, 95% CI 1.113-2.232), use of opioids alone for sedation (odds ratio 1.438, 95% CI 1.046-1.977) and dyspnoea as cause of sedation (odds ratio 1.564 95% CI 1.045-2.341) were independent risk factors for a shorter survival time after starting terminal sedation. Sedated, terminal cancer patients usually live about 1 day. We identified risk factors for a shorter sedation period. This study is limited by its retrospective design and by the frequent use of opioids as the main sedative medications. Prospective studies must be carried out in order to validate these data.

XM02, the first granulocyte colony-stimulating factor biosimilar, is safe and effective in reducing the duration of severe neutropenia and incidence of febrile neutropenia in patients with non-Hodgkin lymphoma receiving chemotherapy

Recombinant granulocyte colony-stimulating factors (G-CSFs) such as filgrastim or lenograstim are being used to treat chemotherapy-induced neutropenia. The aim of the present study was to investigate a new G-CSF, XM02, in comparison to filgrastim in terms of safety and efficacy in the prevention of chemotherapy-induced neutropenia in non-Hodgkin-lymphoma (NHL). A total of 92 patients receiving chemotherapy were randomised in cycle 1 to treatment with daily injections (subcutaneous 5 microg/kg/day) of XM02 (n = 63) or filgrastim (n = 29) for at least 5 days and a maximum of 14 days. In subsequent cycles, all patients received XM02. The mean duration of severe neutropenia (DSN) was 0.5 and 0.9 days in cycle 1 for XM02 and filgrastim, respectively (p = 0.1055). In cycle 1, the incidence of febrile neutropenia (FN) was 11.1% for XM02 and 20.7% for filgrastim (p = 0.1232). The adverse event profile was similar between XM02 and filgrastim. XM02 demonstrated equivalent efficacy and similar safety profile as the reference medication filgrastim. Treatment with XM02 is as beneficial as filgrastim in ameliorating severe neutropenia and FN in patients with NHL receiving chemotherapy. XM02 is safe and well tolerated in the doses applied in this study.

First results of long-term rituximab maintenance treatment in follicular lymphoma: Safety analysis of the randomized phase III trial SAKK 35/03

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Background: Rituximab maintenance has been shown to be effective in patients with follicular lymphoma. The optimal duration of maintenance remains unknown. Methods: We prospectively registered 270 patients with untreated, chemotherapy resistant or relapsed follicular lymphoma. All patients received rituximab induction consisting of 4 weekly doses (375 mg/m2). Responding patients (PR and CR) were randomized to a short maintenance consisting of four doses of rituximab (375 mg/m2) every two months (arm A) or prolonged maintenance consisting of rituximab every two months for a maximum of five years or until progression or unacceptable toxicity (arm B). Primary endpoint was event-free survival. Here we present the safety analysis. Results: From October 2004 to November 2007 165 patients were randomized, 82 in arm A and 83 in arm B. The median follow up is 22.7 months. A total of 442 hematological and non-hematological adverse events were observed, 27 of grade 3 and 6 of grade 4. Five subsequent cancers and 9 grade 3 and 4 infections were reported. Grade 3 and 4 neutropenia occurred in 5 patients, decreased levels of IgG were observed in 19 patients. Four grade 3 infections occurred after 2 years of maintenance. In arm B, maintenance was stopped due to unacceptable toxicity (fever) in 1 patient after 18 months and due to subsequent breast cancer in 1 patient after 20 months. One patient died 4 months after randomization because of ileus and consecutive peritonitis; considered to be unrelated to therapy. Twenty-nine patients are on maintenance for two or more years of which 6 patients are on for three or more years. In this analysis, median duration of the prolonged maintenance is 23.7 months. Conclusions: Rituximab maintenance beyond two years is feasible. We do not have evidence for increased toxicity after 2 years of maintenance. However, close follow up of patients under prolonged rituximab maintenance is necessary. The trial has been closed for accrual but there are still patients on treatment.

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Early switching from morphine to methadone plus acetaminophen in the analgesia of oncologic patientes: A randomized, double-blind, placebo-controlled study

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Background: The objective of this study is to evaluate the efficacy of methadone as substitute for morphine and to investigate if the addition of acetaminophen could reduce the time to attain an equianalgesic methadone dose and to improve the level of analgesia of oncologic patients. Methods: Fifty patients in regular use of morphine with a stable dose for at least 1 week were submitted to the sudden change of this opioid for methadone and randomized in a double blind way to receive acetaminophen (750 mg PO every 6 hours) or placebo for a 7-day period. Data regarding level of pain and side effects were collected and a quality of life questionnaire (QLQ-C30) was applied. Results: Substitution of morphine for methadone resulted in improvement of the toxicity profile with reduction in obstipation (p < 0.001) and xerostomia (p = 0.03). There was improvement in the Numeric Pain Scale (p = 0.03) as well as a significant improvement in the functional level and symptomatology according to the QLQ-C30 questionnaire. Addition of acetaminophen did not reflect improvement in analgesia and also reduction in time of stabilization of methadone doses. At the end of the study most patients (70.8%, p 0.001) preferred to continue with methadone instead of returning to morphine. Conclusions: Early switching from morphine to methadone showed to be safe and efficient in the reduction of side effects improvement of analgesia allowing a comfortable dosage at a lower cost. In this scenario the association with acetaminophen did not reflect improvement of analgesia or reduction in time for equianalgesia.

No significant financial relationships to disclose.

XM02 is superior to placebo and equivalent to Neupogen in reducing the duration of severe neutropenia and the incidence of febrile neutropenia in cycle 1 in breast cancer patients receiving docetaxel/doxorubicin chemotherapy

Background

Recombinant granulocyte colony-stimulating factors (G-CSFs) such as Filgrastim are used to treat chemotherapy-induced neutropenia. We investigated a new G-CSF, XM02, and compared it to Neupogen™ after myelotoxic chemotherapy in breast cancer (BC) patients.

Methods

A total of 348 patients with BC receiving docetaxel/doxorubicin chemotherapy were randomised to treatment with daily injections (subcutaneous 5 μg/kg/day) for at least 5 days and a maximum of 14 days in each cycle of XM02 (n = 140), Neupogen™ (n = 136) or placebo (n = 72). The primary endpoint was the duration of severe neutropenia (DSN) in cycle 1.

Results

The mean DSN in cycle 1 was 1.1, 1.1, and 3.9 days in the XM02, Neupogen™, and placebo group, respectively. Superiority of XM02 over placebo and equivalence of XM02 with Neupogen™ could be demonstrated. Toxicities were similar between XM02 and Neupogen™.

Conclusion

XM02 was superior to placebo and equivalent to Neupogen™ in reducing DSN after myelotoxic chemotherapy.

Trial Registration

Current Controlled Trials ISRCTN02270769

Multivitamins do not improve radiation therapy related fatigue: Results of a double-blind randomized cross-over trial

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Background: Fatigue is a common symptom in cancer patients including those receiving radiation therapy. Multivitamins are broadly used by cancer patients to improve overall health and energy. Methods: We conducted a double blind randomized cross- over trial of multivitamins versus placebo in patients with breast cancer (BC) undergoing radiation therapy (Rxt) in order to evaluate if multivitamins would affect fatigue and quality of life. We randomized patients at the beginning of Rxt treatment to either placebo or Centrum Silver (Wyeth-Whitehall laboratory). At the middle of the radiation treatments patients were switched from placebo to multivitamins and vice versa. Patients answered to the EORTC QLQ C-30 quality of life (QOL) and Chalder fatigue questionnaires at the beginning, the time of switching and at the end of Rxt. Results: We randomized forty patients to either placebo or Centrum Silver. At the middle of the radiation treatments patients were switched from placebo to MVi and vice versa. Patients answered the EORTC QLQ C-30 quality of life (QOL) and Chalder fatigue questionnaires at the beginning, the middle and at the end of Rxt. Both groups experienced decreases in general (p = 0.009; p = 0.001) and physical fatigue scores (p = 0.031; p = 0.029) at the end of the course of placebo compared to the assessment prior to this treatment. We also observed significant improvements in functional (p = 0.026) and symptoms (p = 0.016) score scales of the QOL questionnaire in the patients on placebo. No significant changes were elicited with the use of MVi. We also observed significantly lower rates of fatigue in the patients who had just finished a course of placebo as compared to patients finishinga course of MVi (0 vs 25% p = 0.035). Conclusions: MVi do not improve radiation related fatigue in patients with BC.

No significant financial relationships to disclose.

An open-label, fixed-dose study of bupropion effect on sexual function scores in women treated for breast cancer

BACKGROUND

Sexual morbidity after chemotherapy and hormonal therapy for breast cancer can seriously affect patients' quality of life. Bupropion is an antidepressant that has been reported to increase libido.

OBJECTIVE

To investigate the improvement of sexual function in female breast cancer patients using bupropion.

PATIENTS AND METHODS

We performed an 8-week open trial using bupropion in women diagnosed with breast cancer who had received chemotherapy and were currently receiving adjunctive hormonal therapy. The Arizona Sexual Experience Scale (ASEX) was used. The ASEX scale includes five questions that evaluate sexual function in the following areas: libido, excitability and ability to reach orgasm. Women received oral Bupropion 150 mg/daily for 8 weeks and were evaluated prior to the initiation of the study and again during Weeks 4 and 8.

RESULTS

Twenty patients were included in the study. At the beginning of the study, the mean ASEX score was 23.45 [21.67-25.24] 95% CI. After 4 weeks of treatment, we observed a reduction in the mean ASEX score that persisted until the end of the study, at eight weeks: 18.45 [16.59-20.31] 95% CI (P = 0.0003) and 18.95 [16.60-21.30] 95% CI (P = 0.0024), respectively.

CONCLUSION

In this non-controlled open trial bupropion 150 mg/daily was associated with improved sexual function in women receiving adjuvant systemic treatment for breast cancer.

Use of complementary and alternative medicine by Brazilian oncologists

Complementary and alternative medicine (CAM) is frequently employed by patients with cancer. An extensive survey was conducted among Brazilian cancer physicians to understand their attitude towards CAM. A questionnaire was sent to all 655 members of the Brazilian Cancer Society asking what is their opinion regarding CAM and if they would prescribe any CAM modality for their patients. They were also questioned regarding their degree of awareness of CAM self-administration by their patients. Overall, 119 questionnaires were returned to us (18%). Most oncologists knew at least one type of CAM (96.6%) and 76.7% had previously made use of at least one type of CAM for themselves. We observed that 76 (63.8%) of the oncologists used to ask their patients about CAM utilization and 37.8% described at least one reason to stimulate its use (68.8% as complementary treatment). Only 10% of the oncologists would prescribe at least one type of CAM and this attitude correlated significantly with previous physicians' use of CAM and with being a clinical oncologist as well as with having questioned patients about CAM use. Most oncologists (80.7%) would not indicate the use of CAM, mainly for lack of scientific proof of its efficacy (56.2%). Physicians knew many kinds of CAM and had frequently used some of them themselves, but only a minority of Brazilian oncologists would indicate them. As CAM use is very prevalent in our population, we believe that most of its utilization depends, probably, on patient's own and independent initiatives. However, these results should be viewed with caution because of the low response rate we observed in this study.

Randomized crossover trial of intravenous 5-FU versus oral UFT both modulated by leucovorin: a one-centre experience

Although intravenous (IV) 5-fluorouracil (5-FU) and uracil/futraful (UFT) have comparable antitumour efficacy in the treatment of metastatic colorectal cancer (MCC), we wanted to assess which of these two regimens would be preferred by our patients. We randomized 20 previously untreated patients with MCC at our centre to receive oral UFT or bolus IV 5-FU both associated with leucovorin. After the first cycle patients were crossed over to the other arm. Before the third cycle we left patients to choose one of the regimens to continue their treatment until disease progression. Two patients chose 5-FU and 18 chose UFT (P < 0.001). Fewer side effects (50%) and convenience of home treatment (40%) were the main reasons for their choice for the oral regimen. UFT induced less mucositis (P = 0. 02) and diarrhoea (P = 0. 01). We conclude that convenience and lower toxicity may explain the observed preference for oral UFT.

CK-19 expression by RT-PCR in the peripheral blood of breast cancer patients correlates with response to chemotherapy

BACKGROUND

The recent introduction of sensitive RT-PCR-based techniques for the detection of epithelial antigen expression, such as CK-19, in the peripheral blood and bone marrow of breast cancer patients may provide an opportunity to evaluate tumor response at the molecular level, even in the absence of measurable disease while patients are still receiving chemotherapy.

METHODS

We studied serially collected blood samples of 53 patients with breast cancer before, during, and after adjuvant, neoadjuvant, and palliative chemotherapy to evaluate its effects on the expression of CK-19 measured by RT-PCR.

RESULTS

The percentage of CK-19 RT-PCR positivity decreased consistently from 43% (23/53) before chemotherapy to 14.3% (7/49), and to 18.9% (7/37) after 3 and 6 cycles, respectively (chi-square for linear trend = 7.948; p = 0.0048). Furthermore, there was a significant correlation between a negative CK-19 at three months and the response to chemotherapy (p = 0.024).

CONCLUSION

We conclude that RT-PCR negativity for CK-19 expression at 3 months after the beginning of chemotherapy correlates with tumor response and, as treatment progresses, there is a significant trend for the occurrence of more negative RT-PCR results. Further studies are needed to confirm if this technique can be useful to assess response to chemotherapy in patients without measurable disease and if negativation of CK-19 expression while on chemotherapy is of prognostic significance.

Granisetron is equivalent to ondansetron for prophylaxis of chemotherapy-induced nausea and vomiting: results of a meta-analysis of randomized controlled trials

BACKGROUND

The introduction of serotonin antagonists as antiemetics for prophylaxis of chemotherapy-induced nausea and vomiting represented a major step toward better patient tolerance and adherence to this type of treatment. Several published trials compared different serotonin antagonists without demonstrating clear superiority of any one of them. Because most of these trials compared ondansetron with granisetron, the authors conducted a meta-analysis to determine if the current data available show any therapeutic difference between them.

METHODS

MEDLINE and CANCERLIT databases were searched from 1990 to May 1999, and pertinent article references also were surveyed, without restriction to English language. The authors included all randomized controlled trials (RCTs) that had more than 25 patients per arm and compared ondansetron to granisetron for prophylaxis of acute (A) (< 24 hours) and delayed (D) (> 24 hours) nausea (N) and vomiting (V) induced by highly (H) or moderately (M) emetogenic chemotherapy. Only the first chemotherapy cycle was considered for studies that involved a crossover design.

RESULTS

Fourteen studies with 6467 evaluable patients among the 21 studies retrieved were selected for this meta-analysis. In none of the eight scenarios studied (AHV, AHN, AMV, AMN, DHV, DHN, DMV, and DMN) could the authors detect any significant differences in the antiemetic efficacy of any of these medications.

CONCLUSIONS

The authors conclude that both granisetron and ondansetron have similar antiemetic efficacy for prophylaxis of chemotherapy-induced nausea and vomiting. Because the number of comparative studies that addressed the delayed nausea and vomiting scenarios is low, further RCTs are still needed to confirm these results.

Reverse transcriptase-polymerase chain reaction analysis of cytokeratin 19 expression in the peripheral blood mononuclear cells of normal female blood donors

BACKGROUND

Early detection of haematogenous dissemination of epithelial tumours afforded by the analysis of epithelial antigen expression in the peripheral blood mononuclear fraction (PBMN) and bone marrow may confer a worse prognosis to patients with carcinoma. Cytokeratin 19 is a protein normally expressed by epithelial cells including normal and malignant mammary cells. Previous studies have demonstrated that analysis of cytokeratin 19 expression by the reverse transcriptase-polymerase chain reaction (RT-PCR) can detect one epithelial cell in as many as 10(5)-10(7) haematopoetic cells. Despite its sensitivity concern has been voiced recently about the specificity of this technique owing to the detection of cytokeratin 19 expression in the PBMN of normal volunteers and the bone marrow of patients with haematological malignancies.

AIMS

To assess the sensitivity and specificity of RT-PCR detection of cytokeratin 19 in PBMN of normal female blood donors.

METHODS

Blood was taken from 52 normal female blood donors and PBMN separated through Fycol gradient centrifugation. Cytokeratin 19 was measured using a two step nested RT-PCR assay.

RESULTS

No amplification was found in the first step for any of the samples studied, whereas in the second step amplification was observed in 10 of the 52 samples. Both steps could detect one MCF-7 cell (the cytokeratin 19 positive control) in 10(6) CEM (cytokeratin 19 negative control) cells.

CONCLUSIONS

As both PCR steps are sensitive to the 10(-6) level, performing only the first amplification step may decrease the non-specificity of this method. Further studies are needed to define the specificity and sensitivity of this technique in blood and bone marrow specimens of women with breast cancer.

Leptomeningeal involvement in chronic lymphocytic leukemia identified by polymerase chain reaction in stored slides: a case report

The use of polymerase chain reaction (PCR) for routine detection of clonal immunoglobulin heavy-chain (IgH) gene rearrangements represents an attractive alternative to Southern hybridization analysis not only because PCR protocols are quicker and simpler, but also because of the ability to analyze very small population of cells in search of minimal residual disease. This can be especially important for the detection of clonal malignant cells in locations other than bone marrow or peripheral blood. We describe a case in which central nervous system involvement, a very rare complication of chronic lymphocytic leukemia, was confirmed by PCR analysis for IgH genes rearrangement of the lymphocytes found in cerebrospinal fluid. The cerebrospinal fluid and the peripheral blood lymphocytes (obtained from archival cytospins stored at the time of diagnosis, 5 years before) presented an identical IgH gene rearrangement, as shown by sequence analysis. Thus, the use of PCR for IgH genes rearrangement can be very useful in the detection of monoclonality in samples with a small number of cells and in the confirmation of the common origin of B cells in different specimens of the same patient.

Advances in the biology and treatment of B-cell chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in the western hemisphere. Diagnosis and staging of CLL are usually straightforward, but predicting an individual patient's prognosis is still a challenge. Cytogenetic abnormalities provide important prognostic information in CLL and may show its molecular heterogeneity. A search for oncogene abnormalities continues, although no consistent defects have been identified. New agents such as fludarabine produce high complete remission rates and have generated interest in earlier treatment as a first step in a potential cure. Fludarabine also makes autologous bone marrow transplant feasible as a consolidation therapy. Immunologic abnormalities and minimal residual disease persist in most patients in remission. Combining fludarabine with other active agents and devising effective postremission strategies may change the natural history of CLL.

Retinoblastoma protein expression is frequently altered in chronic lymphocytic leukemia

The detection of abnormalities at the retinoblastoma (RB) locus by cytogenetics, Southern blot, and fluorescence in situ hybridization studies suggests that the RB gene has a role in chronic lymphocytic leukemia (CLL). To further study this role, we determined the level of RB protein present in the mononuclear cell fraction derived from peripheral blood or bone marrow samples from 74 patients with CLL, by Western blotting. Compared to similarly prepared samples from the peripheral blood of normal individuals, the level of RB in CLL cells was less than normal in 42% of patients, equal to normal in 22% of patients, and in excess of normal in 36% of patients. Regardless of whether the source of the sample was blood or marrow or if the patients were untreated or previously treated, similar rates of low, normal, and elevated RB levels were observed. RB protein in the CLL patient samples was never phosphorylated. RB levels showed no correlation with the lymphocyte doubling time or with proliferating cell nuclear antigen levels. Low RB levels could arise from genetic alterations of the RB gene or altered regulation of expression. To determine which was occurring, we stimulated the cells from 27 CLL patients in culture with either phytohemagglutinin or pokeweed mitogen in an attempt to induce RB expression and phosphorylation. Among patients with low levels of RB, expression was induced in 46% (6 of 13), and phosphorylation of RB was seen in 31% (4 of 13). Increased expression of phosphorylated RB was induced in 80% (4 of 5) of patients with normal levels of RB and in 78% (7 of 9) of patients with high levels of RB. This study demonstrates that absent RB expression occurs commonly in patients with CLL. Intrinsic abnormalities of the RB gene may be present in those patients with low levels of RB that could not be stimulated by mitogens, while regulatory abnormalities located in trans to the RB gene may occur in the other half. Given the importance that RB levels play in other cancers, the prognostic implication of low RB levels should be studied in CLL.

Detection of p53 alterations in human astrocytomas using frozen tissue sections for the polymerase chain reaction

The polymorphism of amino acid residue 72 on the human p53 tumor-suppressor gene is a useful marker for detecting intragenic loss of heterozygosity (LOH). We examined the LOH of the p53 gene in human malignant astrocytomas by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis using DNA extracted from frozen tissue sections under histologic examination. Eleven of 16 informative cases (69%) of the malignant astrocytomas were found to have LOH in the p53 gene. Sequential frozen sections were analyzed by immunohistochemistry using anti-p53 antibody PAb1801 to detect overexpression of the p53 protein, which is presumably altered if it is detectable. Ten of the 11 cases that had LOH of the p53 gene overexpressed the p53 protein. Moreover, 4 of the 11 patients with LOH of the p53 gene developed a second neoplasm in addition to an astrocytoma, possibly indicating genetic instability in these patients. These data suggest that alterations of the p53 gene may play an important role in the genesis of malignant astrocytoma. The combination of the PCR-RFLP method and immunohistochemical analysis using frozen tissue sections is a practical diagnostic tool for examination of human malignancies, including astrocytomas. astrocytomas.

Clinical implications of decreased retinoblastoma protein expression in acute myelogenous leukemia

The retinoblastoma (RB) protein levels in blast-enriched mononuclear fractions from the peripheral blood of 33 newly diagnosed patients with acute myelogenous leukemia were studied. Ten patients who had previously been treated were also analyzed, nine of whom had achieved prior complete remission. Low RB protein expression was found in 13 of 43 (30%) of the acute myelogenous leukemia patients as determined by Western blotting and immunochemical analysis. Of particular interest among the 20 newly diagnosed patients treated with the same therapeutic regimen, the median survival was 39 days for those with low RB protein expression compared to 333 days for those with high levels of RB protein expression in their leukemic cells (P less than or equal to 0.02). This preliminary study suggests that decreases of RB protein expression in peripheral blood of myeloid leukemic cells occur frequently and may be associated with shortened survival of acute myelogenous leukemia patients.

Prognostic value of proliferating cell nuclear antigen expression in chronic lymphoid leukemia

Chronic lymphocytic leukemia (CLL) is a usually indolent disease that can assume an aggressive clinical course in some patients. To develop assays that would be predictive of how a particular patient's disease would evolve, we studied the expression of proliferating cell nuclear antigen (PCNA) by Western blotting in 40 patients with CLL. The concentration of PCNA, a cofactor for delta DNA-dependent DNA polymerase, is indicative of the proliferative state of the cell. Significantly lower PCNA levels were observed in earlier stage CLL when compared with more advanced disease. The leukemic cell proliferative rate, assessed by lymphocyte doubling time and flow cytometry, also correlated significantly with the level of PCNA expression. These results suggest that a high level of PCNA in the cells of CLL patients at presentation identifies a subgroup of patients whose CLL cells have a higher proliferative activity and who may, therefore, have a potentially shorter survival.

Severe, symptomatic, dose-limiting hypophosphatemia induced by hepatic arterial infusion of recombinant tumor necrosis factor in patients with liver metastases

Twenty-two patients with liver metastases received 45 courses of recombinant tumor necrosis factor (rTNF) by hepatic arterial infusion in doses ranging from 12.5 to 175 micrograms/m2/d for 5 days by continuous infusion. The induction of statistically significant, dose-related, severe, albeit transient, hypophosphatemia (less than 1.0 mg/dl) associated with clinically significant, right-sided myocardial dysfunction and severe lassitude was observed. These side effects were promptly reversed after rTNF was stopped and intravenous phosphate supplementation was started. As no significant or consistent increase in urinary phosphate excretion was detected, the rTNF-induced hypophosphatemia probably resulted from an intracellular shift of phosphate. Since tumor regression was clearly associated with the lowest levels of serum phosphate, hypophosphatemia may be important in the antitumor effects of rTNF.

Relevance of the chemical charge of rhodamine dyes to multiple drug resistance

Previously, we have shown that multiple drug resistant (MDR) Friend leukemia cells (FLC) are cross-resistant to the positively-charged dye, Rhodamine 123 (Rho 123), and that this resistance can be reversed by verapamil (VER). In the present study we used two zwitterionic rhodamine analogs, Rhodamine 116 and Rhodamine 110, and another positively-charged analog, Rhodamine 6G, to determine whether drug accumulation, resistance and modulation were affected by changes in the charge of these compounds. While there was no differential sensitivity between sensitive and resistant FLC to zwitterionic rhodamines, there was marked differential toxicity between these cell types for the positively-charged analogs. The IC50 values were 1000- and 100-fold greater in resistant than in sensitive cells for Rho 123 and Rho 6G respectively. Intracellular drug accumulation was significantly higher in sensitive as compared to resistant cells for both Rho 123 and Rho 6G, but little difference in drug uptake between these two cell types was observed for Rho 110 and Rho 116. It was also found that the intracellular to extracellular ratio of the positively-charged compounds was greater than unity in both sensitive and resistant cells whereas for the zwitterionic analogs this ratio was less than 1. Furthermore, this ratio of drug uptake was found to be significantly higher for Rho 6G than for Rho 123, which correlated with the high oil:water partition coefficient of Rho 6G (115.6). In MDR cells, verapamil increased Rho 123 and Rho 6G accumulation by 9.4- and 8.6-fold respectively. In addition, IC50 values in resistant cells were reduced greater than 100-fold for Rho 6G and greater than 1000-fold for Rho 123 in the presence of 10 micrograms/ml of verapamil. In contrast, less than 2-fold reduction of IC50 values for both of the zwitterionic analogs could be obtained under the same conditions. These results indicate that the chemical charge of rhodamines plays an important role in their differential accumulation, cytotoxicity and sensitivity to modulators such as verapamil, in sensitive and multi-drug resistant cells. The data also suggest that increased lipophilicity of the positively-charged rhodamines may increase their ability to accumulate in, and subsequently kill, MDR cells.

Tumor and serum beta-2-microglobulin expression in women with breast cancer

To investigate whether the tumor expression of beta-2-microglobulin (beta 2-M) could serve as a marker of tumor biologic behavior, the authors studied specimens of breast carcinomas from 60 consecutive female patients. Presence of beta 2-M was analyzed by immunohistochemistry. No significant correlations were found between tumor beta 2-M expression and several histologic attributes such as type, histologic and nuclear grades, mitotic index, necrosis, vascular invasion, and lymphocytic infiltration. Likewise, beta 2-M was not associated with markers of disease extension such as TNM, (UICC, classification of malignant tumors) staging and axillary lymph node involvement or with estrogen, progesterone, and glucocorticoid receptor levels. However, there was a significantly positive association between tumor beta 2-M expression and the degree of lymphocytic infiltration in the tumor tissue. Beta 2-M serum levels were determined by an enzyme-linked immunosorbent assay in samples from 22 of the above women. Although some of the highest values had been obtained in women with larger (T4) primary tumors, the authors failed to detect any statistical relationship between beta 2-M expression in the tumor with serum levels or between serum beta 2-M and the above histologic, laboratory, and clinical factors.