Immunobead-PCR: a technique for the detection of circulating tumor cells using immunomagnetic beads and the polymerase chain reaction.

The presence of tumor cells in the circulation may predict disease recurrence and metastases. We have developed a sensitive technique for the detection of carcinoma cells in blood, using immunomagnetic beads to enrich for epithelial cells and the polymerase chain reaction to identify a tumor marker. The colon carcinoma cell line SW480, homozygous for a K-ras codon 12 mutation, was used to establish optimal conditions. The SW480 cells were serially diluted in normal blood and incubated with immunomagnetic beads labeled with a monoclonal antibody specific for epithelial cells. Cells bound to the beads were retrieved using a magnetic field and the presence of K-ras codon 12 mutations determined by a polymerase chain reaction based analysis. SW480 cells could be detected in dilutions up to 1 SW480 cell/10(5) leukocytes in whole blood.

Significance of molecular marker-positive cells after autologous peripheral-blood stem-cell transplantation for non-Hodgkin's lymphoma.

PURPOSE: To evaluate the significance of molecular marker-positive cells in a cohort of non-Hodgkin's lymphoma (NHL) patients undergoing high-dose chemotherapy and autologous peripheral-blood stem-cell transplantation (PBSCT). PATIENTS AND METHODS: Twenty-eight PBSC transplants have been performed in 24 patients with poor-prognosis NHL. Molecular analysis of the t(14;18) (q32;q21) translocation (bcl-2/immunoglobulin [Ig] heavy-chain joining locus [JH] fusion) or antigen receptor gene rearrangements was performed to determine the presence of lymphoma cells at presentation, in PBSC harvests, and before and after autologous PBSCT. Kaplan-Meier estimates of survival and Cox regression analyses were used to test the effect of bone marrow involvement, tumor-cell contamination of PBSCs, disease stage, and chemotherapy sensitivity at transplantation, and presence of marker-positive cells post-PBSCT on disease-free and overall survival. RESULTS: Thirteen of 24 patients (54%) are alive following PBSCT at a median follow-up time of 654 days (range, 193 to 1,908). Nine patients are in complete remission (CR) at day 216 to 1,799 (median, 805) and four are alive following relapse (day 440, 573, 1,188, and 1,908). Eleven patients (46%) have died: three of transplant-related complications at day 0, 1, and 13, and eight of recurrent disease (day 132 to 1,330; median, 451). Longitudinal marker studies post-PBSCT showed that of 16 relapse events, 13 (81%) were positive for the lymphoma marker at or before clinically documented relapse. Marker studies became negative post-PBSCT in nine of nine patients who entered and remained in CR. Disease-free survival (DFS) was significantly shortened in patients in whom marker-positive cells were detected in serial samples posttransplantation (P = .006). Cox regression analysis showed that patients in this group had a 24 times higher risk of relapse (P = .03). CONCLUSION: The results show that the reappearance or persistence of marker-positive cells after autologous PBSCT is strongly associated with relapse.

Single high doses of cyclophosphamide enable the collection of high numbers of hemopoietic stem cells from the peripheral blood.

We used single high doses of cyclophosphamide (4 g/m2) to produce rebound increases in peripheral blood (PB) stem cells (PBSC) during recovery from myelosuppression, enabling their collection by apheresis for later autotransplantation. Thirty-three courses of cyclophosphamide were given to 30 patients with malignant lymphoma, multiple myeloma, or solid tumors. The neutrophil count was less than 0.5 x 10(9)/liter for a mean of 6.9 days (median 7 days), and fever occurred in 17 of 33 courses. Positive blood cultures occurred in two patients, one of whom died. The mean peak level of PB granulocyte-macrophage colony-forming units (CFU-GM) was 1517 x 10(3)/liter (median 2447 x 10(3)/liter), a 14-fold increase above the mean in normal subjects. The peak occurred at a mean of 16.6 days (median 16 days) after cyclophosphamide, generally coinciding with the time to reach 1.0 x 10(9) neutrophils per liter. Normal or minimally involved bone marrow and a rapid rise in leukocyte count during recovery were independent variables correlated to the peak of the rebound increase in PB CFU-GM levels. Previous chemotherapy and the duration of neutropenia were additional independent variables in the group with peak PB CFU-GM levels of greater than 1000 x 10(3)/liter. The mean total CFU-GM collected after a mean of five aphereses was 43.8 x 10(4)/kg body weight (BW) (median 35.5 x 10(4)/kg BW), significantly correlated with the mononuclear cell yield. We conclude that single 4 g/m2 doses of cyclophosphamide effectively produce high levels of PBSC, particularly but not exclusively in patients with normal or minimally involved bone marrow and who have not had intensive recent chemotherapy.

Preferential epidermotropism in adult t-cell leukemia-lymphoma.

Three patients with systemic T-cell leukemia-lymphoma presented with generalized pruritic skin rash which was clinically nondiagnostic. Biopsies revealed infiltration of the superficial dermis by atypical lymphoid cells with epidermal exocytosis (Pautrier abscesses) producing a pattern of histologic involvement indistinguishable from that of mycosis fungoides and Sézary syndrome. This striking similarity suggests that the phenomenon of preferential epidermotropism is not confined to mycosis fungoides and Sézary syndrome, but may be a property shared by other subpopulations of T-lymphocytes.

Reversal of human platelet aggregation by low concentrations of nitroglycerin in vitro in normal subjects.

The potential reversal of platelet aggregation in vitro by nitroglycerin in low concentrations was explored using both optical aggregometry and electron microscopy. Venous blood was collected from a cohort of normal volunteers (20 men and 10 women) aged 21 to 65 years. Aggregation in platelet-rich plasma was induced by adenosine diphosphate in concentrations just sufficient to maintain a steady state of aggregation, without a spontaneous disaggregation phase (3.5 to 5 microM). Administration of nitroglycerin after the induction of aggregation caused both inhibition of the primary wave of developing aggregation and marked disaggregation. This combined effect was maximal when nitroglycerin was added at 0.5 minute after the beginning of aggregation. The observed reversal of platelet aggregation by nitroglycerin was concentration-dependent. Significant effects occurred with nitroglycerin concentrations greater than or equal to 10(-8) M. Concentration associated with 50% reversal of aggregation was 1.52 +/- 0.24 (SEM) x 10(-6) M. Electron microscopy revealed that 10(-6) M nitroglycerin induced a significant reduction in both platelet clumping and morphologic changes associated with aggregation. The results of the current study suggest a beneficial antiplatelet effect of nitroglycerin in restoring homeostasis in the face of incipient platelet aggregation. The clinical use of nitroglycerin in patients with acute ischemic syndromes may rest on this action.

Molecular detection of residual lymphoma cells in peripheral blood stem cell harvests and following autologous transplantation.

Twenty-seven patients with non-Hodgkin's lymphoma (NHL) have undergone peripheral blood stem cell (PBSC) harvesting for autologous transplantation (Tx). A molecular marker was found at presentation in 23/27 patients. Immunoglobulin heavy chain (IgH) or T cell receptor beta (TCR beta) rearrangements were detected by Southern blotting or the polymerase chain reaction (PCR) in 13 patients; PCR detected the bcl-2/JH fusion in 10 patients. Fifteen autologous PBSC transplants have been performed in 11 patients. In 5/11 patients, the marker was present in at least one PBSC collection (in four patients, every PBSC collection was positive). Survival data are available for nine patients (two early deaths); three patients relapsed and died (221 - 930 d), one is alive and in relapse (354 + d) and five are alive and in complete remission (330 - 1290 + d). These findings suggest that tumour cell contamination of PBSC harvests is not uncommon. Whether these cells are clonogenic and contribute to disease relapse remains to be elucidated. The presence of residual disease at the time of transplantation and the reappearance (or persistence) of marker positive cells post-transplantation both appear to be poor prognostic factors for disease-free survival.

Factors affecting blood stem cell collections following high-dose cyclophosphamide mobilization in lymphoma, myeloma and solid tumors.

Sixty patients with malignancy were enrolled in a study of high-dose chemotherapy and peripheral blood stem cell transplantation (PBSCT). Stem cells were harvested prior to PBSCT using high-dose cyclophosphamide (CY) mobilization (4 or 7 g/m2) with collection of a median of 4.6 x 10(8)/kg mononuclear cells (range 0.2-9.5) and 21.6 x 10(4)/kg colony forming unit-granulocyte/macrophage (CFU-GM) (range 0.1-220). Forty-seven patients were mobilized once, 11 required two cycles and two required three cycles. Eight patients (13%) failed to reach the optimum CFU-GM target (greater than 15 x 10(4)/kg) following CY mobilization. A number of factors identified those patients who were likely to achieve optimum CFU-GM collections with CY mobilization. These included the use of the higher CY mobilization dose, a longer interval from last chemotherapy cycle to mobilization, and a higher premobilization bone marrow CFU-GM level. Patient's age, the degree of bone marrow infiltration, the nature of disease or the number of pre-mobilization chemotherapeutic cycles did not affect the ability to collect optimum CFU-GM numbers. Whilst the mobilization procedure was associated with moderate non-hematologic toxicity, significant hematological morbidity was observed primarily in patients mobilized using the 7 g/m2 dose. Refinements to the protocol, in particular the use of hematopoietic growth factors, are currently under investigation.

Evaluation of a commercial radioassay for the simultaneous estimation of vitamin B12 and folate, with subsequent derivation of the normal reference range.

A commercial assay kit method for the simultaneous estimation of vitamin B12 and folate concentrations has been evaluated. Values derived for folate by a microbiological assay and vitamin B12 by a verified radioassay showed good correlation with the investigated method. The clinical sensitivity of the assay for detecting deficient concentrations of vitamin B12 and folate was comparable to that of the non-commercial methods and other more definitive clinical procedures. Establishment of reference ranges, based on accepted statistical criteria, are discussed and such ranges are contrasted with those proposed by the manufacturer. The kit method is time and labour saving compared with the non-commercial methods.

A complex translocation in acute promyelocytic leukemia.

The breakpoints of a complex three-way translocation involving chromosomes X, #15, and #17 were resolved in a case of acute promyelocytic leukemia (APL). It is now apparent that similar cases of variant chromosome translocations are found in both chronic granulocytic leukemia (CGL) and APL. The morphological and clinical findings in this case emphasize the variability found in some cases of APL.

Novel translocations in acute nonlymphocytic leukemia. Two cases involving chromosome 21, band q22.

We present two cases in which translocations involving 21q22 were found at presentation in acute nonlymphocytic leukemia (ANLL). The first of these translocations, t(3;21)(q26-q27;q22), is previously unknown in ANLL, but appears indistinguishable from that reportedly associated with Philadelphia-positive chronic myelogenous leukemia. The second case involves t(15;21)(q21-q22;q22), a translocation previously undescribed in ANLL. Both of these exchanges involve 21q22 plus another chromosome region associated with leukemogenesis. We attempted to interrelate these cytogenetic data with the oncogenic significance of 21q22.

A rare translocation (4;11)(q21;p14-15) in an acute lymphoblastic leukemia expressing T-cell and myeloid markers.

A 21-year-old male presented with a large mediastinal mass and a white cell count of 420 x 10(9)/L. A diagnosis of acute lymphoblastic leukemia (ALL) was made, with 90% of cells in the bone marrow (BM) and 99% in the peripheral blood (PB) being lymphoblasts (FAB L1). Cytogenetic analysis of these cells revealed a rare variant of the t(4;11) translocation involving chromosome arm 11p rather than 11q, namely t(4;11)(q21;p14-15). The standard form of the (4;11) translocation has been associated with leukemias with mixed-lineage phenotypes. Three cases of ALL with t(4q;11p) have previously been reported. One of these cases showed phenotypic heterogeneity involving myeloid and lymphoid lineages. The leukemia reported here also exhibits lymphoid/myeloid features. Immunophenotyping of the blasts showed that most of the cells were positive for CD2, CD5, CD7, CD10 (CALLA), CD34, and HLA-DR. A significant proportion of the cells expressed CD33. These results suggest a biphenotypic rather than a biclonal disease. Molecular analysis showed rearrangement of both immunoglobulin heavy-chain genes (JH) and of a single allele of the T-cell receptor (TCR) gamma 1 gene, while retaining germline TCR beta genes.

The effect of food on oral melphalan absorption.

Fifteen patients receiving oral melphalan (4.2-5.3 mg/m2) for a variety of neoplastic disorders were studied. Ten patients received the drug on separate occasions, with and without a standardized breakfast. Eight of these patients also received an IV bolus dose (5 mg/m2) to determine bioavailability. Serial melphalan plasma samples were taken over 5 h after administration and assayed by high-performance liquid chromatography. The median area under the curve (AUC) when taken fasting was 179 (range 95-336) ng X h X ml-1, and when taken with food, 122 (47-227) ng X h X ml-1, the median reduction being 39% (P less than 0.01). In one patient, who died before completing the study, the drug was not detectable at all after being taken with food. In the eight patients who were also given IV melphalan, the median terminal melphalan half-life (57 min, range 38-71) was no different from its oral half-life [55 (27-104) min fasting; 55 (30-72) min with food] (P greater than 0.1). In these patients bioavailability was 85% (26-96)% when the drug was taken fasting and 58% (7-99)% when taken with food (P less than 0.025). Median clearance following IV administration was 362 ml/min/m2 (range 104-694). It was found that the melphalan level in a single plasma sample drawn 1.5 h after administration was highly predictive of oral melphalan AUC (rs = 0.915, P less than 0.1). This study suggests that to ensure optimum absorption of the drug, melphalan should not be taken with food.

Renal clearance and protein binding of melphalan in patients with cancer.

The renal clearance of melphalan and the fraction unbound in plasma were determined after intravenous infusion of 5 mg/m2 over 5 min in nine patients with cancer to obtain information regarding the mechanism of renal handling of melphalan. Four of the patients underwent bone marrow transplantation and also received an IV dose of 220 mg/m2. Total melphalan clearance after the 5 mg/m2 dose ranged from 66.0 to 272 ml/min per m2; the percentage of the dose excreted unchanged in urine, from 2.5% to 92.8%; renal clearance, from 4.1 to 188 ml/min per m2; the fraction unbound in plasma, from 0.0598 to 0.460; and t1/2 beta, from 39.4 to 84.3 min. Unbound melphalan clearance and renal clearance calculated from the unbound fraction in plasma for each patient ranged from 441 to 3356 ml/min per m2 and 15 to 961 ml/min per m2 respectively and were not related to serum albumin, serum creatinine or creatinine clearance. The percentage of the dose excreted and melphalan renal clearance were not related to urine flow. There was evidence of active secretion of melphalan in the kidney an possible reabsorption. There were no significant paired differences in melphalan disposition between the high- and low-dose studies. Highly variable renal clearance involving active secretion may contribute in part to large interpatient differences in the total plasma clearance of melphalan in patients with cancer.

Effect of L-leucine on oral melphalan kinetics in patients.

Melphalan uptake in the intestine has recently been shown to be an energy-dependent process which is affected by metabolic inhibitors. It is therefore theoretically possible that amino acids in food could reduce melphalan absorption by competing for uptake at the sites of absorption in the intestine. Since L-leucine has been shown to be the most potent inhibitor of melphalan transport into cells in vitro, this amino acid was chosen for the present study in patients. Oral melphalan (4.5 +/- 0.5 mg/m2) was given to ten fasting patients with and without a 2-g oral dose of L-leucine on separate randomized occasions at least 1 week apart. Melphalan plasma levels were measured by high-performance liquid chromatography (HPLC) for 5-h after dosing. L-Leucine plasma levels were measured by HPLC before and at 1 h after dosing. The area under the curve for melphalan was lower in seven of the patients after L-leucine. Plasma L-leucine levels 1 h after melphalan administration were 15.4 +/- 3.7 micrograms/ml fasting and 35.4 +/- 5.2 micrograms/ml after L-leucine. The results indicate that L-leucine can reduce plasma melphalan levels in some patients, probably through a reduction in absorption of the drug from the gastrointestinal tract. However, the effect, like that of food, is highly variable.

High dose hydroxyurea in collection of Philadelphia chromosome-negative stem cells in chronic myeloid leukaemia.

High dose hydroxyurea (HU) was used in a pilot study to assess its efficacy in mobilizing Philadelphia (Ph) chromosome negative progenitor cells in chronic myeloid leukaemia (CML). Five patients received 12 g/M2 oral HU in divided doses. Side effects were minimal, allowing outpatient administration. Nine to fourteen days later 4 patients achieved a mean leukocyte nadir of 3.5 x 10(9)/L (Range 2.4-4.9) and a mean platelet nadir of 99 x 10(9)/L (Range 95-108). Peripheral blood mononuclear cells (PB-MNC) sampled prior to the HU priming were 100% Ph positive. Between 10 and 18 days post HU, 3 patients achieved a marked reduction (80-100%) in the number of Ph positive metaphases in PB-MNC collected by apheresis. One patient failed to achieve any Ph suppression. Polymerase chain reaction analysis (PCR) for the bcr-abl fusion product remained positive in all samples. Rapid rises in CFU-GM numbers were associated with a return to 100% Ph positive metaphases however slower rises represented recovery with predominantly Ph negative cells, allowing apheresis collection of these cells. We conclude that HU induces a reproducible leukocyte nadir with sufficient stem cell mobilization for potential autologous transplantation. Higher doses of HU together with early and intensive apheresis is required to maximize Ph negative progenitor cell harvests.

Methadone-maintenance outcomes for Hispanic and African-American men and women.

Six-month methadone-maintenance response and outcome were examined for African-American and Hispanic men and women in a large urban sample. A consistent pattern of improvement was indicated for both races and genders on the addiction severity index (ASI). There were virtually no statistically significant differences in ASI outcomes between Hispanics and African-Americans and men and women using conventional analysis of variance (ANOVA) procedures. Results from an additional equivalence analysis, however, indicated that baseline to 6-month changes for the different groups were generally not similar enough to consider them equivalent. Urine toxicologies obtained during the 6-month treatment period were also not statistically equivalent by race and gender. Evaluating outcomes by gender and race are discussed, as are the implications of using equivalence tests when examining group differences.

Collection and cryopreservation of peripheral blood progenitor cells in chronic granulocytic leukaemia--a comparison of treated and untreated patients.

Buffy coat cells were collected by leukapheresis from 14 patients with C.G.L. and one patient with M.M.M. Six of the C.G.L. patients had received busulphan at intervals varying between 401 and 38 d before leukapheresis. Significantly more CFUc's could be collected per leukapheresis in untreated patients and in those patients not treated within 105 d prior to leukapheresis. Survival of CFUc's following freezing was significantly less in the 3 most recently treated patients. These results suggest that in C.G.L. patients recently treated with busulphan, both the number of CFUc's in the peripheral blood and the ability of these cells to survive the freeze thaw process are reduced. However, sufficient CFUc's could theoretically be collected, stored and recovered post-thaw from one leukapheresis to allow complete haematopoietic restoration in all but 2 patients.

Node-based T cell lymphoma. The clinical, immunological and morphological spectrum.

Four cases of node-based T cell lymphoma are presented. The tumours had 2 distinct morphologic patterns. Two cases showed a polymorphous proliferation of pleomorphic lymphoid cells, small lymphocytes, epithelioid cells and arborizing small vessels while the others displayed a monomorphous infiltrate of large atypical lymphoid cells characterized by granular nuclei with numerous tortuous folds to produce a 'squiggly' appearance. One case showed a progression from one histological pattern to the other. Confirmation of the T cell nature of these lymphomas was based on the demonstration of E-rosette formation by morphologically atypical lymphoid cells which also stained positive for acid alpha-naphthyl acetate esterase activity. The patients had an average age of 52 yr and presented with a variable distribution of lymphadenopathy and a predominance of extranodal involvement. Two cases disclosed hypergammaglobulinaemia, one of whom had a paraproteinaemia of IgM-k type. All patients responded poorly to standard combination chemotherapy, 2 expiring 48 and 53 mth after onset of symptoms.

Surface marker studies in chronic lymphocytic leukaemia and non-Hodgkin's lymphoma.

Immunological surface marker techniques were applied in a study of 29 cases of chronic lymphocytic leumaemia and 22 of non-Hodgkin's lymphoma. Surface marker characteristics distinguished 2 subtypes of B lymphocytes. Chronic lymphocytic leukaemia was a monoclonal proliferation of B lymphocytes which produced spontaneous rosettes with mouse erythrocytes and had faintly immunofluorescent surface immunoglobulin. The majority of non-Hodgkin's lymphomas also had their origin from B lymphocytes but in contrast, this subtype did not show receptors for mouse erythrocytes and their surface immunoglobulin was brightly staining and demonstrated "capping". The clonal origin of nodular lymphomas could also be demonstrated on frozen sections stained for surface immunoglobulin. Two cases of true histiocytic lymphoma were identified. The current information available on surface marker characteristics of the leukaemias and lymphomas is reviewed.