Biomedical subjects

R Mick

Publications and source records attributed to R Mick.

At least 37 records · Page 2Linked to original sources

PubMed1997

Thymidylate synthase expression and response to neoadjuvant chemotherapy in patients with advanced head and neck cancer.

BACKGROUND: Thymidylate synthase (TS), an essential enzyme in DNA synthesis, is a target for the fluoropyrimidines, an important group of antineoplastic agents used widely in the treatment of head and neck cancer. PURPOSE: We evaluated relationships between the level and/or pattern of tumor TS expression and response to fluorouracil (5-FU)-based neoadjuvant chemotherapy in patients with advanced head and neck cancer. METHODS: Tumor specimens from 86 patients were available for this retrospective analysis. The patients were enrolled in four consecutive phase II studies that tested combinations of 5-FU, leucovorin, and cisplatin with or without added methotrexate plus piritrexim or interferon alfa-2b (IFN alpha-2b). TS protein expression in the tumors was assessed by use of the TS 106 monoclonal antibody and standard immunohistochemical staining techniques. TS immunostaining was classified according to its level of intensity (TS 0-1 = low, TS 2 = intermediate, and TS 3 = high) and according to its extent (focal pattern = less than 25% of tumor cells positive; diffuse pattern = greater than or equal to 25% of tumor cells positive). Data from 79 patients were available for an analysis of tumor TS expression and patient/tumor characteristics; 70 patients were assessable for their response to neoadjuvant chemotherapy. RESULTS: There was a statistically significant association between the level of tumor TS expression and the degree of tumor differentiation; a higher proportion of patients whose tumors exhibited TS 0-1 immunostaining had undifferentiated or poorly differentiated tumors than patients whose tumors exhibited TS 2 or TS 3 immunostaining (P = .04, Jonckheere-Terpstra trend test). Among the 70 patients who were assessable for response to neoadjuvant chemotherapy, TS 3 tumor immunostaining was associated with a lower rate of complete response (i.e., complete disappearance of clinically detectable disease for a minimum of 4 weeks from time of initial determination) than was TS 2 or TS 0-1 immunostaining, but this association was not statistically significant (P = .09, exact trend test); among the 39 patients who were treated with regimens that included 5-FU, leucovorin, cisplatin, and IFN alpha-2b, this inverse association between TS immunostaining intensity and response was statistically significant (P = .02, exact trend test). Tumor TS immunostaining intensity and overall survival were not found to be associated. Patients with tumors exhibiting a focal pattern of TS immunostaining have experienced significantly longer survival than patients with tumors exhibiting a diffuse pattern; for the 53 patients with diffuse tumor TS immunostaining, the median survival was 24.7 months, whereas the median survival has not yet been reached for the 22 patients with focal tumor TS immunostaining (P = .04, two-tailed logrank test). However, the survival advantage for the focal versus diffuse TS immunostaining pattern was limited to patients whose tumors also exhibited a TS 3 level of immunostaining intensity. CONCLUSIONS AND IMPLICATIONS: Characterization of tumor TS expression may be of value in identifying patients with advanced head and neck cancer who would benefit from fluoropyrimidine-based neoadjuvant chemotherapy.

Antimetabolites, Antineoplastic↗

PubMed1997

Cycles of dose-intensive chemotherapy with peripheral stem cell support in persistent or recurrent platinum-sensitive ovarian cancer.

OBJECTIVE: The objective was to determine the toxicity and surgically documented response rate of sequential high-dose chemotherapy with peripheral stem cell support in patients with persistent or recurrent cisplatin-sensitive ovarian cancer. METHODS: Fourteen patients (average age, 45 years) were treated with cyclophosphamide (4.5 g/m2), followed by granulocyte colony-stimulating factor (G-CSF)-stimulated peripheral stem cell harvests. The subsequent regimen prescribed three courses of carboplatin (1 g/m2) and cyclophosphamide (1.5 g/m2 with 2-mercaptoethanesulfonate) every 2 weeks with stem cell support. This was followed by three courses of paclitaxel at 250 mg/m2 every 2 weeks with G-CSF support only. Six patients were entered on the basis of a positive second-look laparotomy and 8 patients had a first recurrence after at least a 6-month disease-free interval. RESULTS: Fourteen patients were entered and 12 patients completed all planned courses of therapy (mean time, 13 weeks). Normal hematopoiesis was reestablished after each cycle. Hospitalization for neutropenic fever occurred in 11/93 cycles (11.8%). Thirteen patients required blood transfusions and in 12 patients platelet transfusions were given. One patient had grade 3 neurotoxicity. An initial elevated CA 125 returned to normal in 7/8 patients (88%) and 71% of patients with measurable disease responded to therapy. There were 2 pathologic complete responders (PCR), making the PCR rate 2/14 or 14% (0-35%). CONCLUSION: Although this regimen was well tolerated and clinical response rates were high, the surgically documented response rate was not clearly superior to conventional salvage regimens in platinum-sensitive patients.

Adult↗

PubMed1997

Performance and quality of life outcome in patients completing concomitant chemoradiotherapy protocols for head and neck cancer.

This study evaluated post-treatment performance and quality of life (QOL) outcome in head and neck cancer (HNC) patients treated with organ preservation, intensive chemoradiotherapy (FHX). Participants were 47 Stage II-IV HNC patients with no evidence of disease at least one year post-completion of organ preservation, concomitant FHX treatment. Patients were assessed via a semi-structured in-person interview, standardized measures of QOL (FACT-H&N, CES-D), performance (PSS-HN) and patients' perception of residual side effects. Disease, treatment and toxicity data were retrieved from medical charts and protocol records. The most salient performance impairment was inability to eat a normal solid food diet, with 50% of patients able to eat soft foods or take liquids only. This specific functional deficit was not related to global QOL, nor to specific quality of life dimensions. Dry mouth, the most frequent and severe residual effect, was not associated with outcome diet, depression or QOL. Residual pain, seen in only 15% of patients, appeared to influence both functional and QOL parameters as well as being a marker for other troublesome symptoms. Twenty-three per cent of patients were depressed; depression was associated with past problems related to alcohol abuse. Decreased QOL and increased depressive symptomatology were related to total number and severity of residual effects. The data highlight the importance of systematic study of QOL dimensions and caution against making assumptions about patients' experience of particular disease and treatment sequelae.

Activities of Daily Living↗

PubMed1997

CCR5 genotypes in sexually active couples discordant for human immunodeficiency virus type 1 infection status.

Persons who are homozygous for the delta32 polymorphism of the CCR5 chemokine receptor gene are highly protected against human immunodeficiency virus type 1 (HIV-1) infection. Previous studies described 54 HIV-1-discordant couples in whom no virus transmission occurred despite extensive sexual contact. The possible role of the delta32 polymorphism in the lack of HIV-1 transmission between these partners was studied. No participants were homozygous for the delta32 allele, but the proportion that was heterozygous was higher among HIV-1-seronegative than HIV-1-seropositive partners (28% vs. 11%, P = .05). This association was seen in heterosexual couples (P = .03) but not in homosexual couples (P = .74). Among white persons, who are most likely to carry the delta32 allele, 38.9% of HIV-1-uninfected and 5.6% of HIV-1-infected heterosexual partners were heterozygous (P = .04). These data are consistent with a possible association between the heterozygous delta32 genotype in heterosexual sex partners and partial protection against HIV-1 infection, and they emphasize the importance of analyzing different risk groups in studies of host factors that influence infection.

Alleles↗

PubMed1997

Phase I study of vinorelbine and ifosfamide in advanced non-small-cell lung cancer.

PURPOSE: We designed a phase I dose-escalation study of vinorelbine on a novel (daily-times-three) schedule with ifosfamide with granulocyte colony-stimulating factor (G-CSF) support to define the dose-limiting toxicity (DLT) and maximum-tolerated dose (MTD) of vinorelbine in this combination. PATIENTS AND METHODS: Cohorts of patients with stage IIIB or IV non-small-cell lung cancer (NSCLC) and no prior chemotherapy received vinorelbine starting at 15 mg/m2 on days 1, 2, and 3, and ifosfamide starting at 2.0 g/m2 on days 1, 2, and 3 with G-CSF support for all patients. Cycles were repeated every 21 days. Plasma vinorelbine concentrations were also analyzed. RESULTS: Forty-two patients were treated. The median age was 58 years (range, 34 to 75) and 41 had a performance status of 0 or 1. The DLT was neutropenia and sepsis at a maximum-administered vinorelbine dose of 35 mg/m2 for 3 days. The recommended phase II dose was vinorelbine 30 mg/m2 with ifosfamide 1.6 g/m2 both given on 3 consecutive days. The overall response rate was 40% (17 of 42; all partial responders). The median survival duration was 50 weeks, with a 1-year survival rate of 48%. Pharmacokinetic analysis showed that vinorelbine in this combination and on this schedule is cleared 1.5 to two times faster than in single-agent once-weekly studies. CONCLUSION: Myelosuppression is the DLT of this regimen with no major subjective toxicities. With tolerable toxicity and an encouraging 1-year survival rate of 48%, further investigation of this new vinorelbine schedule is warranted in this and other combination regimens.

Adult↗

PubMed1997

Pharmacokinetic and pharmacodynamic evaluation of the topoisomerase inhibitor irinotecan in cancer patients.

PURPOSE: We conducted a pharmacokinetic and pharmacodynamic evaluation of irinotecan (CPT-11) and determined the effect of race and sex on disposition and toxicity of CPT-11. We tested the efficacy of acetaminophen (AAP) to phenotype SN-38 glucuronidation. PATIENTS AND METHODS: Forty patients received a dose of 145 mg/m2 of CPT-11 as a 90-minute infusion. Total CPT-11, SN-38, and SN-38G were quantitated in plasma and urine samples. Following administration of 1 g AAP, urinary concentrations of AAP and AAP-glucuronide (AAP-G) were assessed. RESULTS: CPT-11 exhibited a mean elimination half-life (t1/2) of 8.8 hours, an average clearance (CL) of 14.6 L/h/m2, and a mean volume of distribution at steady-state (Vdss) of 136 L/m2. SN-38 and SN-38G had low plasma availabilities (3% and 10% relative to CPT-11), with mean t1/2 values of 11.6 and 10.5 hours, respectively. Urinary recovery accounted for 15% of the dose. Race and sex had no effect on the plasma availability of CPT-11, SN-38, and SN-38G. The applicability of biliary index (BI) in predicting dose-limiting intestinal toxicity was validated. Patients who developed grade 3 or 4 toxicity had significantly higher index values compared with patients with grade 0 to 2 toxicity (P = .001). There was no difference in the incidence and severity of toxicity based on race and sex. AAP was a poor predictor of SN-38 glucuronidation. CONCLUSION: The high degree of interpatient variability in parameter estimates suggests pharmacogenetic variation or differential induction or inhibition of the sequential metabolic pathway of CPT-11, as well as variability in transport systems. The low urinary recovery indicates substantial biliary excretion and supports the significant correlation between intestinal toxicity and BI. Black patients are not at increased risk of toxicity. An assessment of individual differences in SN-38 conjugation remains to be established.

Antineoplastic Agents↗

PubMed1996

Loss of heterozygosity from the short arm of chromosome 8 is associated with invasive behavior in breast cancer.

Loss of heterozygosity (LOH) from the short arm of chromosome 8 (8p) is frequent in many human cancers, including breast, colon, prostate, and bladder cancers. LOH occurs in two regions of 8p, 8p21 and 8p22, and suggests the presence of two separate tumor suppressor genes. In breast cancers, 8p LOH occurs in both early and late clinical stage tumors, while in colon, prostate, and bladder cancers, there is an association between 8p LOH and advanced clinical stage. We investigated this discrepancy by comparing 8p LOH in infiltrating ductal carcinomas (IDC) to breast cancers of earlier clinical stage, i.e., tumors with no invasion [ductal carcinoma in situ (DCIS)-only tumors]. We used three markers which sample several reported loci of 8p LOH. We microdissected tumor from paraffin blocks of 39 IDC and 23 DCIS-only breast cancers and amplified tumor/normal DNA pairs for the microsatellite markers D8S254 (8p22), D8S133 (8p21.3), and NEFL (8p21). All cases of IDC were informative with at least one marker, with a combined rate of LOH of 46%. The results for each marker were [no. LOH/no. informative (%)]: D8S254, 8/26 (31%); D8S133 12/31 (39%), and NEFL, 9/25 (36%). In the DCIS-only group, all 23 were informative for at least one marker, but 8p LOH was absent. We conclude that 8p LOH from 8p21-22 is frequent in IDC of the breast, but absent in DCIS-only cases, and may play a role in breast cancer progression by conferring invasive ability.

Breast Neoplasms↗

PubMed1996

Peripheral blood mononuclear cell dihydropyrimidine dehydrogenase activity in volunteers with and without diabetes mellitus.

It has been reported that cancer patients with diabetes mellitus receiving a continuous infusion of 5-fluorouracil (5-FU) have more toxicity and higher plasma 5-FU levels that patients without diabetes mellitus. Dihydropyrimidine dehydrogenase (DPD) is the initial and rate-limiting enzyme in the catabolism of 5-FU. DPD activity in peripheral blood mononuclear cells has been reported to correlate inversely with 5-FU plasma levels in patients. We therefore undertook a study to compare the activity of DPD in peripheral blood mononuclear cells of human subjects with and without diabetes mellitus. The study groups comprised 43 volunteers with and 39 without diabetes mellitus, and peripheral blood mononuclear cell DPD activity was assayed on samples obtained between 8 a.m. and 11 a.m. DPD activity was not decreased in diabetic subjects. There was no relationship between DPD activity and gender body mass index, or race. There was a modest correlation between DPD activity and age (r=0.19, P =0.08). We conclude that increases in 5-FU-related toxicities in diabetics must be related to factors other than peripheral blood mononuclear cell DPD activity.

Adult↗

PubMed1996

Etoposide combined with interferon alfa-2b: novel exploitation of established etoposide pharmacokinetics and pharmacodynamics.

PURPOSE: To construct an efficient pilot study design to determine whether interferon alfa-2b modifies the pharmacokinetics and pharmacodynamics of continuous-infusion etoposide. PATIENTS AND METHODS: A two-stage randomized 2 X 2 factorial design was used to evaluate interferon alfa-2b at two doses (2 or 10 MU/m2/day SQ for 3 days) and two schedules (interferon alfa-2b administered before or concurrent with 72-hour continuous-infusion etoposide). Etoposide was administered at 75, 100, or 125 mg/m2/day. In lieu of comparing the experimental arms to an etoposide-alone control arm to determine effect of interferon alfa-2b dose and schedule, a novel analytic approach was used. The effect of interferon alfa-2b on etoposide-induced leukopenia was assessed indirectly by comparison of the observed white blood cell (WBC) nadir to the nadir predicted from an established pharmacodynamic model for single agent etoposide. RESULTS: Based on 29 patients, dose-normalized 24-hour total and estimated free etoposide concentrations did not differ with interferon alfa-2b dose or schedule. Patients treated with interferon alfa-2b before etoposide had, on average a WBC nadir 545 +/- 225 cells microliter lower than that predicted by a pharmacodynamic model for etoposide alone. An optimal nonlinear model for leukopenia was defined by interferon alfa-2b schedule in addition to 24-hour etoposide concentration. CONCLUSION: A novel study design and statistical analysis provided an efficient preliminary evaluation of the combination of interferon alfa-2b with etoposide in a modest number of patients. Exploitation of a previously validated pharmacodynamic model allowed evaluation of interferon alfa-2b effect and eliminated the need for an etoposide-alone control arm. The pharmacokinetics of continuous-infusion etoposide at doses from 75 to 125 mg/m2/day appear to be unchanged by interferon alfa-2b at the doses and schedules tested and the combination appears to be feasible. We hypothesize that leukopenia may be enhanced when interferon alfa-2b is administered before etoposide, especially at a higher dose of interferon alfa-2b.

Adult↗

PubMed1996

Individualized dosing of amonafide based on a pharmacodynamic model incorporating acetylator phenotype and gender.

Amonafide is extensively metabolized, including conversion by N-acetylation to an active metabolite. Our previous studies have shown that fast acetylators of amonafide have increased toxicity, and we have recommended doses of 250 and 375 mg m-2 day-1 for 5 days, for fast and slow acetylators, respectively. Despite phenotype-specific dosing, significant variability in leukopenia persisted. The goal of this study was to construct and validate a pharmacodynamic model-based dosing strategy for amonafide, to try to further decrease inter-patient variability in leukopenia. The model was based on a training data set of 41 patients previously treated with amonafide. The first cycle nadir WBC was modelled as a function of dose, acetylator phenotype and baseline patient factors. This model was validated prospectively on patients similar to those in our previous studies. Based on the training data set, the optimal model was defined by three factors: acetylator phenotype, gender, and pretreatment WBC. Using this model and a target WBC nadir of 1700 microliters-1, six dosing strata were prospectively evaluated. A total of 24 fast acetylators received either 238 or 276 mg m-2 day-1 and 20 slow acetylators received between 345 and 485 mg m-2 day-1. The mean (+/- SE) error (deviation from target nadir) was 430 (+/- 240) cells microliters-1. Submaximal treatment (yielding grade 0-1 leukopenia) was limited to 20% of patients, while 55% experienced grade 2-3 toxicity. A complex dosing strategy for amonafide is feasible, employing prospective acetylator phenotyping, model-guided dosing, and adaptive control.

Acetylation↗

PubMed1996

Dose-escalation trial of cladribine using five daily intravenous infusions in patients with advanced hematologic malignancies.

PURPOSE: The optimal dose and schedule for cladribine (2CdA) therapy of malignant hematologic diseases have not been determined. This dose-escalation study was designed to assess toxicity when 2CdA is given using five daily 1-hour intravenous infusions. PATIENTS AND METHODS: Forty-two adults with advanced hematologic malignancies were treated in one of nine cohorts, starting at 2.5 mg/m2/d for 5 days. Plasma drug concentrations were measured by high-performance liquid chromatography. Responses were assessed by bone marrow biopsy on day 15 of the first course and by clinical measurements after each course. Patients received one to four courses each. RESULTS: Nonhematologic toxicity was mild, and dose-limiting nonhematologic toxicity was not observed, even at the highest dose level of 21.5 mg/m2/d. In particular, neurotoxicity was not observed. The maximum-tolerated dose (MTD) was not identified. However, prolonged cytopenias and severe infections were more common in the higher 2CdA dose cohorts. Logistic regression analysis suggested that severe hematologic toxicity was associated with pretreatment platelet count and performance status (PS). Good-risk patients were identified as having a PS of 0 and platelet count > or = 80,000/microL, PS of 1 and platelet count > or = 120,000/microL, or PS of 2 and platelet count > or = 160,000/microL. Sustained complete responses (CRs) and partial responses (PRs) were observed in eight patients. CONCLUSION: 2CdA can be administered using five daily 1-hour infusions at 21.5 mg/m2/d without dose-limiting nonhematologic toxicity. Unlike continuous intravenous infusions, neurotoxicity was not observed using this schedule. Further dose escalation may be possible in good PS patients with adequate platelet counts.

Adult↗

PubMed1996

Pharmacodynamics of fluorouracil-based induction chemotherapy in advanced head and neck cancer.

PURPOSE AND METHODS: To optimize the biochemical modulation of fluorouracil (5-FU), we administered the pure I-stereoisomer of leucovorin (LV) as a 132-hour continuous intravenous infusion (CIV) with cisplatin 100 mg/m2, 5-FU 640 mg/m2/d as a 120-hour CIV, and interferon alfa-2b (IFN) at 2 MU/m2/d for 6 days for three cycles (I-PFL-IFN). Pharmacologic parameters included morning (AM) and afternoon (PM) plasma concentrations of 5-FU, LV and its active metabolite 5-methyl tetrahydrofolate (MTHF), and dihydropyrimidine dehydrogenase (DPD) activity in peripheral mononuclear cells. RESULTS: Eighty-nine patients were treated (86 stage IV). Neutropenia and mucositis were the most common toxicities. Sixty-six percent achieved a complete remission (CR). There was a trend for higher PM versus AM 5-FU concentrations (median, 1.64 v 1.51 mumoles/L; P = .08), but not for LV plus MTHF (P = .66). The mean +/- SD DPD activity was 0.21 +/- 0.14 nmol/min/mg and did not correlate with plasma concentrations of 5-FU or LV plus MTHF or clinical toxicities. Higher PM 5-FU concentrations correlated with worse leukopenia (P = .04) and severity of mucositis (P = .04). PM 5-FU concentration was higher in women than in men (P = .07), with no apparent difference in severity of toxicities. The maximum 5-FU concentration was higher in CR than non-CR patients (median, 2.01 v 1.54 mumoles/L; P = .02) and higher in women than men who achieved a CR (median, 2.77 v 1.91 mumoles/L; P = .03). No correlation of CR with dose-intensity was found. CONCLUSION: L-PFL-IFN is active in stage IV head and neck cancer. 5-FU concentration is a significant predictor of toxicity. In women, optimization of response outcome requires a higher 5-FU concentration. Individualized 5-FU dosing to obtain higher 5-FU plasma concentrations may be indicated.

Adolescent↗

PubMed1996

Limited-sampling models for irinotecan pharmacokinetics-pharmacodynamics: prediction of biliary index and intestinal toxicity.

PURPOSE: To construct limited-sampling models (LSMs) for irinotecan (CPT-11) pharmacokinetic (PK) measures. MATERIALS AND METHODS: The recommended phase II dose of weekly CPT-11 administered as a 90-minute infusion is 145 mg/m2 with granulocyte colony-stimulating factor (G-CSF) and maximal antidiarrheal support. Diarrhea is the dose-limiting toxicity. Previously, we demonstrated a highly significant correlation between severity of diarrhea and biliary index (BI), the estimated biliary exposure of SN-38. BI was the product of total CPT-11 area under the concentration-time curve (AUC) and the relative area ratio of SN-38 to SN-38 glucuronide (SN-38G). At 145 mg/m2, PK data were available for 40 patients; 36 were also assessable for intestinal toxicity. Total plasma concentrations of CPT-11, SN-38, and SN-38G from 1.0 to 11.5 hours from the start of the infusion were evaluated. CPT-11 concentration at each time point, t, is denoted by CPT-11t. LSMs were constructed by stepwise linear regression, on a training set (n = 25), and were validated on a test set (n = 15). RESULTS: LSMs for CPT-11, SN-38, and SN-38G AUCs displayed excellent fit to the training set (R2 = .87, 0.75, and .98, respectively). AUCCPT-11 = 5.25 x CPT-11(3.0) + 20.60 x CPT-11(11.5) + 1,520.53; AUCSN-38 = 5.38 x SN-38(3.5) + 33.61 x SN-38(11.5) - 7.73; and AUCSN-38G = 10.73 x SN-38G9.5 + 20.66 x SN-38G11.5 + 142.69. BI at each time point (denoted BIt) was calculated as CPT-11t x (SN-38t/SN-38Gt). Several promising LSMs were defined by BI3.5 paired with BI7.5 (R2 = .63) or BI9.5 (R2 = .76), or BI5.5 paired with BI9.5 (R2 = .76). Predicted BI from each model (categorized into low, intermediate, or high) accurately predicted observed intestinal toxicity grade (P < or = .005). CONCLUSION: These LSMs appear to accurately predict PK parameters of CPT-11. Notably, BI, predicted from several LSMs, accurately predicted intestinal toxicity and thus may be useful for future trials that use adaptive control with feedback.

Antineoplastic Agents, Phytogenic↗

PubMed1996

Refractory cytopenia with multilineage dysplasia: further characterization of an 'unclassifiable' myelodysplastic syndrome.

Myelodysplastic syndromes (MDS) characterized by multilineage cytopenias and dysplasia but lacking an increase in blasts, with no Auer rods or monocytosis, do not exactly fit any of the categories of the French-American-British (FAB) classification of MDS and are often diagnosed as refractory anemia (RA), refractory anemia with ringed sideroblasts (RARS), or 'unclassifiable' MDS. It has been suggested that these 'unclassifiable' cases form a distinct subset with a clinical behavior more like that of refractory anemia with excess of blasts (RAEB) than that of RA or RARS, but few studies have been undertaken that characterize this group. We compared the clinical, hematologic, morphologic and cytogenetic features of 18 such patients - for whose disease we propose the designation 'refractory cytopenia with multilineage dysplasia' (RCMD) - to those of 42 patients meeting the FAB criteria for RA or RARS (14 patients) and RAEB (28 patients). Our results show that cytopenias in RCMD are more severe than those in RA or RARS, but are similar to those in RAEB. Erythroid hyperplasia and dyserythropoiesis are the main findings in bone marrow specimens of RA or RARS, but the major features in RCMD are multilineage proliferation and dysplasia, which, except for the lack of increased blasts resemble the findings in RAEB. Only 1/14 patients (7%) with RA or RARS had an abnormal karyotype, whereas RCMD resembled RAEB in terms of the frequency (41 vs 50%, respectively) and type of karyotypic lesions. Abnormalities of chromosomes 5 and 7 (excluding del(5q) as an isolated finding) or complex aberrations were seen only in RCMD and RAEB. in RCMD, the median survival was 24 months, with a 4-year survival rate of48 +/- 13%, intermediate between the findings in RA/RARS (107 months and 77 +/- 12%, respectively) and RAEB (18 months and 27 +/- 9%, respectively). Our data indicate that RCMD is a distinct subset of MDS, with an unfavorable clinical outcome. The designation 'refractory cytopenia with multilineage dysplasia' emphasizes the differences between such cases and the primarily dyserythropoietic, indolent subgroups of MDS, such as RA or RARS.

Adult↗

PubMed1996

Bone marrow transplantation for the treatment of haematological disorders in Down's syndrome: toxicity and outcome.

We report 18 patients with Down's syndrome who underwent bone marrow transplantation, and review nine previously published patients. The indications for transplant in the combined group of 27 patients were acute lymphoblastic leukaemia in 14 cases (52%), acute myeloid leukaemia in 11 cases (41%) and aplastic anemia in two cases (7%). Transplants were autologous in five cases (19%) and allogeneic in 22 cases (81%); of the 22 allogeneic transplants, 16 donors were HLA-matched siblings. In all patients the conditioning regimen included total body irradiation of 7.5 Gy or more, and/or contained cyclophosphamide of 120 mg/kg or more. Seven patients (26%) had fatal pulmonary disease including pneumonitis and pulmonary hemorrhage. Five patients (19%) had significant airway problems including three with severe mucositis who required intubation for airway protection, one with severe mucositis with partial airway obstruction that required observation in the intensive care unit but did not require intubation, and one with Candida albicans laryngitis with development of a glottic web. Nineteen patients (70%) survived beyond 100 days post-transplant. There was no clear association between 100-day survival and the use of any particular agent or regimen used for conditioning or graft-versus-host disease prophylaxis, and the majority of patients tolerated high-dose cyclophosphamide, high-dose cytosine arabinoside, high-dose busulfan, total body irradiation, cyclosporin A, and methotrexate. There appeared to be more early deaths in patients who received the combination of cyclophosphamide and total body irradiation, compared with those receiving the combination of busulfan and cyclophosphamide or those receiving the combination of cytosine arabinoside and total body irradiation. Also, the use of methotrexate was associated with a greater number of early deaths, compared with cyclosporin A. At 3 years, life table estimates of freedom from relapse, relapse-free survival and survival were 75%, 44% and 48%, respectively. The estimated cumulative risk of death due to a non-leukaemic cause at 3 years was 39%. The data show that Down syndrome patients can tolerate the commonly used transplant conditioning regimens with acceptable toxicity; however, there is a strong suggestion in the data that the rates of life-threatening and fatal toxicity are higher than would be expected to occur in patients without Down's syndrome. Patients with Down's syndrome may have a predisposition to fatal pulmonary complications and reversible airway problems during the immediate post-transplant period.

Adolescent↗

PubMed1996

Human papilloma virus and p53 in head and neck cancer: clinical correlates and survival.

Recent studies have shown that p53 mutations are frequently found in cancer of the head and neck, whereas others have indicated that human papilloma virus (HPV) infection may be involved. Thus far, no studies have examined both p53 and HPV in the same patient population and correlated the results with clinical characteristics and outcome. The purpose of this study was to examine any interrelationship between p53 and HPV in patients with squamous cell carcinoma (SCC) of the head and neck. We also planned to correlate the experimental findings with clinical characteristics, known risk factors, and treatment outcome to determine whether any prognostic factors could be detected. Archival material from 66 patients with SCC of the head and neck were selected for study based on the availability of tissue from the primary tumors prior to treatment. A data base was constructed containing all clinical parameters at the time of diagnosis and risk factors. Genomic DNA was isolated and amplified using PCR, followed by SSCP analysis and direct genomic sequencing of all variants to detect p53 mutations. Two independent methods were used for HPV detection: (a) PCR amplification using primers homologous to the E6 region of HPV 16, 18, and 33, followed by RFLP analysis; and (b) PCR amplification with HPV L1 consensus primers, followed by triple restriction enzyme digestion. The results were entered into the data base for statistical analysis. Twenty-four percent of patients were found to have p53 mutations, and 18% were positive for HPV infection. Only one patient was positive for both. Tonsilar cancer was strongly correlated with HPV (P = 0.0001) and inversely correlated with p53 (P = 0.03). The only clinical parameter associated with p53 mutation was a trend toward a heavier smoking history. A subset analysis of the patients with tonsilar cancer revealed inverse correlations with smoking (P = 0. 015) and alcohol use (P = 0.05). Also, white patients with SCC of the tonsil were more likely to be HPV positive (P = 0.015). No significant relationships with outcome were detected with either p53 or HPV in the entire population. A subset analysis of patients with stage IV disease revealed that HPV infection was correlated with overall survival. This is the largest study to date to examine both p53 and HPV in patients with SCC of the head and neck. Our results suggest that HPV may be involved in the development of these cancers in patients without traditional risk factors and that HPV-related cancers are more prevalent in the white race.

Adult↗

PubMed1995

BCL6 encodes a sequence-specific DNA-binding protein.

Chromosomal rearrangements of BCL6 are commonly associated with diffuse large-cell lymphomas. We set out to determine the DNA-binding site of a glutathione-S-transferase fusion protein containing the BCL6 zinc finger region by employing cyclic amplification and selection of targets (CASTing). From oligonucleotides containing 16 central random bases, sequences binding to the protein on glutathione-coated beads were repeatedly selected and amplified by polymerase chain reaction (PCR). The binding sites were cloned and sequenced. A consensus, TTTNNNGNNATNCTTT, was obtained. Protein binding studies of double-stranded oligomers containing point mutations within the 3' CTTT confirmed the binding specificity of this part of the consensus. In addition, evidence indicated that some of the base pairs held constant in the oligonucleotides used for CASTing also contributed to binding.

Base Sequence↗

PubMed1995

Optimizing selection of patients for major lung resection.

OBJECTIVES: It is not known whether a normal diffusing capacity for carbon monoxide permits safe lung resection in patients with marginal spirometric values, or whether normal spirometric values negate the adverse effects of a low diffusing capacity. The purposes of this study were (1) to determine the best predictors of morbidity and mortality and (2) to assess whether interactions exist between diffusing capacity and spirometry that help estimate outcome after major lung resection. DESIGN: A retrospective analysis of 376 patients who underwent lung resection was performed. Three hundred three had lung cancer and 73 had other disease. Two hundred eighty-four underwent lobectomy/bilobectomy and 92 had pneumonectomy. We assessed the relationship of 23 preoperative variables to 18 postoperative events classified into categories as pulmonary or cardiac complications, overall morbidity, and operative mortality. RESULTS: The best single predictor of complications was the percent predicted postoperative diffusing capacity. The incidences of pulmonary and cardiac complications, morbidity, and mortality were inversely related to predicted postoperative diffusing capacity percent (p < 0.004 for each). Multivariate logistic regression analyses identified only predicted postoperative diffusing capacity percent and age as significant independent predictors of pulmonary complications, morbidity, and death, and these with prior myocardial infarction predicted cardiac complications. There were no interactions between percent predicted postoperative forced expiratory volume in 1 second and predicted postoperative diffusing capacity percent in estimating risks of complications. CONCLUSION: Predicted postoperative diffusing capacity percent is the strongest single predictor of risk of complications and mortality after lung resection. There is little interrelationship of predicted postoperative diffusing capacity percent and predicted postoperative forced expiratory volume in 1 second, indicating that these values should be assessed independently in estimating operative risk.

Female↗