Low-dose radiotherapy for lymphoid lesions of the orbit and ocular adnexa.

PURPOSE: There is no agreement within the radiation oncology and ophthalmic communities regarding the treatment of lymphoid lesions of the orbit and ocular adnexa. The authors report their experience with the use of low-dose radiation therapy for malignant and benign lymphoid masses of the orbital region in a series of 54 patients treated between 1985 and 1993. METHODS: All patients received 2 Gy per day for a total of 24 Gy, except when the lesion was extensive, in which case the therapy was 1.5 Gy per day for a total of 25.5 Gy. A diagnosis was established by incisional surgical biopsy in 26 patients and aspiration cytology in 28 patients. Those with a malignant or an indeterminate diagnosis were evaluated with a modified Ann Arbor staging system. RESULTS: Low-dose radiation therapy produced a complete response in 100% of the orbital lymphoid lesions. This local control was maintained in 52 patients (96%) for the first year and in 51 patients (95%) for 5 or more years with a mean follow-up of 7 years. One patient died of causes unrelated to the malignant lymphoma after the first year of observation. The mean age of the 54 patients was 67 years, and the range was 37 to 90 years. The mean ages of presentation for each location were: orbit, 67 years; conjunctiva, 68 years; lacrimal gland, 66 years; and eyelids, 72 years. The female-to-male ratio was 1.25:1 (34 women and 20 men). In this series, 9 patients had benign processes, 38 patients had non-Hodgkin's lymphoma, and 7 patients had abnormalities of indeterminate cause. All histologic subtypes of non-Hodgkin's lymphoma involving the orbit responded equally well to therapy. Forty-five patients had clinically staged disease as follows: stage I, 21 patients; stage II, 4 patients; stage III, 2 patients; and stage IV, 18 patients. Benign disease, diagnosed in 9 patients, was not staged. CONCLUSION: Low-dose radiation therapy proved effective in treating lymphoid lesions of the orbital area. No treatment-limiting complications occurred. The only early side effects were mild xerophthalmia and chemosis in 50% of patients, and the only chronic side effect was mild xerophthalmia in 33% of patients. Cataracts, corneal ulcerations, and retinal injury were not observed.

Detection of membrane-associated human chorionic gonadotropin and its subunits on human cultured cancer cells of the nervous system.

Cultured human cancer cells from the nervous system, which included brain cancers, neuroblastomas, medulloblastomas, and retinoblastomas, were analyzed by analytical flow cytometry for the presence of membrane-associated human chorionic gonadotropin (hCG), its subunits, and fragments. Live cells and a panel of monoclonal antibodies directed to epitopes located in three different sites of the hCG molecule were used in the analysis. For in vivo studies, the cultured human glioma cells were grown in athymic (nude) mice, and their tumors were excised and fixed in Bouin's fixative, and embedded in paraffin for subsequent immunocytochemical analysis of tissue sections. Cells from a benign uterine leiomyoma were used as a negative control. Membrane-associated and cytoplasmic hCG, its subunits, and its fragments were present in cells from all the cancers studied. These results correlate with our in vitro and in vivo studies which showed the presence of translatable levels of hCG beta mRNA in all cancers, including the cancers of the nervous system, proving that these malignant neoplasms are no different from carcinomas, sarcomas, malignant lymphomas, or leukemias in that they all have the same biochemical denominator. Our findings give the scientific basis for the use of active and/or passive immunization against hCG for prevention or as a primary adjuvant therapy for these types of cancers.

Metastatic phenotype correlates with high expression of membrane-associated complete beta-human chorionic gonadotropin in vivo.

BACKGROUND: Investigations using living human cancer cells and the nude mouse model were conducted to evaluate the expression of human chorionic gonadotropin (hCG) in various cancers grown in vitro and in vivo. The aim was to determine whether membrane-associated hCG in any of its forms is a characteristic metastatic marker, and at what levels or ratios. METHODS: Human cancer cell lines known to produce tumors that metastasize spontaneously when grown in nude mice (n = 4) were compared with those that do not produce such tumors (n = 4) using analytical (quantitative) flow cytometry. Monoclonal antibodies directed to epitopes of intact hCG (hCG-holo) and its subunits, including beta-human chorionic gonadotropin with its carboxy-terminal peptide (hCG beta-CTP), allowed for the determination of hCG beta-CTP/hCG-holo ratios. RESULTS: No significant difference in hCG beta-CTP/hCG-holo ratios was found between the cultured human cancer cells that do not metastasize spontaneously (ratio = 2.39) and those that do (ratio = 2.13), and no difference was seen in their growth rate in nude mice. However, the cells isolated from tumors that do not metastasize spontaneously showed a decrease in their ratios to values less than 1. They reverted to their original values after reestablishment in culture and subsequent passages. In contrast, the ratios shown by cells isolated from tumors that metastasize spontaneously increased to 3 to 6 times their original values in culture, then reverted to their original values after reestablishment in culture and subsequent passages. CONCLUSIONS: To our knowledge, these data demonstrate the following for the first time: 1) There is a direct in vivo correlation between human cancer cells that metastasize spontaneously in nude mice and the expression of membrane-associated complete hCG beta (hCG beta-CTP); and the correlation identifies this molecule as a characteristic metastatic phenotype marker. 2) The marked ratio variations under different conditions indicate that the metastatic phenotype is an unstable event. 3) Growth and local invasion in vivo correlates with the expression of hCG-holo.

The accumulation of multiple genetic abnormalities in individual tumor cells in human breast cancers: clinical prognostic implications.

PURPOSE: Human solid tumors undergo multiple genetic evolutionary changes as they evolve from the normal state to advanced stages of malignancy. This study characterizes the degree of advancement of primary human breast cancers in their genetic evolutionary pathways, and determines if this is of clinical significance. MATERIALS AND METHODS: Correlated cell-by-cell measurements of cell DNA content, HER-2/neu protein content per cell, and H-ras protein content per cell were obtained by means of multiparameter flow cytometry on primary tumors from 95 patients with clinically localized breast cancer. Laboratory findings were correlated with subsequent clinical course in 91 of these patients. RESULTS: Multiple genetic abnormalities were found to accumulate in individual cells in primary human breast cancers. Almost all tumors contained subsets of cells with one, two, or three abnormalities per cell in various combinations. After a median follow-up time of 32 months, 11 of 13 patients with early recurrence had primary tumors in which more than 5% of cells were hypertetraploid, overexpressed HER-2/neu protein, and overexpressed H-ras protein (triple-positive cells). The duration of disease-free survival among patients with primary tumors that contained triple-positive cells was significantly shorter than for patients whose tumors did not contain triple-positive cells. The presence of subpopulations of cells with maximums of only one abnormality per cell or only two abnormalities per cell, in any combination, was of no prognostic significance. Among patients whose nodal status was known, 12 had recurrent disease, and all had positive axillary nodes. Among 36 patients known to have negative axillary nodes, no recurrence has been reported to date. CONCLUSIONS: The number of genetic abnormalities that accumulate in individual cells in primary breast cancers reflects the degree of advancement of a tumor in its genetic evolutionary sequence, and provides useful clinical prognostic information. Because follow-up duration is still relatively short, and because disease in node-negative patients tends to recur later than in node-positive patients, it is still too early to know if three measurements per cell will be sufficient to improve prognosis in node-negative disease.

Aneuploidy in breast cancer: a fluorescence in situ hybridization study.

Although ploidy is associated with the development and progression of most breast cancers, the value of flow cytometric ploidy as a clinical prognostic factor remains controversial. The technique of fluorescence in situ hybridization (FISH) can be used not only to determine overall ploidy, but also to assess the over-representation or under-representation of specific chromosomes in interphase cells. This information may be of prognostic value. We studied 84 primary breast cancers and 20 metastatic tumors by FISH, using chromosome-specific fluorescent centromeric probes. Of these, 100 cases were also studied by DNA flow cytometry. The FISH studies were concordant with DNA flow cytometry with regard to distinguishing aneuploid from diploid tumors in 78% of cases. The FISH data suggested that aneuploidy arises by a process of chromosome complement doubling with subsequent chromosome loss. In tumors that exhibited evidence of more than one round of chromosome complement doubling, the selective accumulation of multiple copies of specific chromosomes or chromosome segments was common. Multiple copies of chromosomes centromeres 1, 3, and 17 were accumulated selectively in the cells of individual tumors more frequently than chromosomes centromeres 7, 11, and 16. Multiple copies of chromosomes centromeres 10 and 20 were selectively accumulated only rarely, if at all. Aneuploidy in breast cancer can be divided into distinct stages using fluorescence in situ hybridization techniques. The stages of aneuploidy provide potential landmarks in the genetic evolution of this disease with possible links to chromosome-specific evolutionary changes.

Human chorionic gonadotropin-beta subunit gene expression in cultured human fetal and cancer cells of different types and origins.

BACKGROUND: The authors' previous investigations using living cultured human cancer cells and cells isolated from cancer tissues, analytical flow cytometry, and monoclonal antibodies directed to epitopes located in five different sites of the human chorionic gonadotropin (hCG) molecule, identified the presence of membrane-associated hCG, its subunits and fragments, by cells from all cancers, irrespective of type and origin, indicating that the expression of these sialoglycoproteins is a common phenotypic characteristic of cancer. Although benign neoplasms do not express these compounds, cultured human embryonic and fetal cells also express the same materials. To corroborate these findings, five fetal cell lines and 28 cancer cell lines were randomly selected from those previously studied, to determine the presence of translatable levels of hCG-beta (hCG beta) mRNA. METHODS: All cell lines were grown under identical conditions. Determination of hCG beta mRNA was made by extracting the total RNA from the cells, followed by synthesis of cDNA with RNase H- reverse transcriptase and polymerase chain reaction amplification using specific hCG beta-luteinizing hormone-beta (hLH beta) primers. The presence of amplified hCG beta cDNA was corroborated by hybridization of the product with an hCG beta-specific oligonucleotide and Southern blot analyses of the hybridization products. Gestational choriocarcinoma cells and HeLa adenocarcinoma of cervical cells, known producers of biologically active hCG, were positive control subjects, and human pituitary cells were used as negative control subjects. RESULTS: The results showed single and multiple hCG beta gene activation by the fetal cells and the different types of cancer, indicating that at any given time, there is the possibility of activation of as many as four genes of the six genes of the hCG beta-hLH beta gene cluster, even though alternative gene splicing cannot be ruled out. CONCLUSIONS: In addition to the authors' previous findings, the results of these studies support the concept that cancer is a problem of development and differentiation, and, to the authors' knowledge, prove definitively for the first time that synthesis and expression of hCG, its subunits, and its fragments, is a common biochemical denominator of cancer, providing the scientific basis for studies of its prevention and/or control by active and/or passive immunization against these sialoglycoproteins.

Assessing sequential oncogene amplification in human breast cancer.

Studies of amplification and/or overexpression of c-myc, HER-2/neu, and H-ras in breast cancer have shown that each is associated with a poor prognosis. The purpose of this study was to explore the possibility that there is a preferred sequence of amplification of these oncogenes in breast cancer. The frequencies of amplification and patterns of co-amplification of c-myc, HER-2/neu, and H-ras were studied in a group of 84 breast cancers. The data suggested a preferred sequence of amplification that consisted of c-myc amplification-HER-2/neu amplification-H-ras amplification. This model was supported by loglinear analysis. In addition, the levels of amplification of JC-A, a DNA fragment newly isolated from a patient with advanced breast cancer, were studied in 61 of these cases. The data suggested that JC-A amplification occurred early. Loglinear analysis supported a model in which JC-A amplification occurred either before or after c-myc amplification but was unrelated to Her-2/neu or ras amplification.

Preferred genetic evolutionary sequences in human breast cancer: a case study.

Multiparameter flow cytometry studies were performed on the cells of an aggressive human breast cancer at the time of diagnosis and at relapse. The aneuploid cells that overexpressed large amounts of both HER-2/neu and ras survived intensive chemotherapy and were responsible for tumor relapse. At relapse, these cells were shown to overexpress simultaneously at least five oncogenes: HER-2/neu, ras, EGF receptor, p53 and c-myc. A partial reconstruction of the genetic evolutionary sequence in this tumor indicated that HER-2/neu overexpression was an early step in the sequence. Subsequent HER-2/neu overexpression, EGF receptor overexpression and p53 protein overexpression were each associated with ras overexpression. The data suggest that ploidy and oncogene overexpression cannot be used as independent clinical prognostic factors. The ability to characterize tumors according to the degree of advancement in the genetic evolutionary might serve as a basis for genetic staging for adjuvant therapy.

Autologous bone marrow transplantation in adults with non-Hodgkin's lymphoma: a Southwest Oncology Group study.

Patients with non-Hodgkin's lymphoma (NHL) who fail conventional chemotherapy have a dismal outcome. Reports from single institutions utilizing high-dose chemoradiotherapy plus Autologous Bone Marrow Transplantation (ABMT) in this setting suggest three-year disease-free survival between 15-60 per cent. From 1985 to 1989 the Southwest Oncology Group performed a prospective multi-institutional study involving ABMT in relapsed/refractory NHL. Forty-five patients, ages 6-60 (median 38), with relapsed NHL were treated with high-dose cyclophosphamide (60 mg/kg/d x 2), total body irradiation (200 cGy/d x 6), and autologous unpurged bone marrow. Histologic subtypes included high grade lymphoma (10), intermediate grade lymphoma (33), and low grade lymphoma (2). Disease status pre-ABMT was sensitive relapse (16), resistant relapse (13), and untreated relapse (16). The actuarial three-year event-free survival and overall survival for all patients were 27 per cent and 38 per cent respectively. Causes of failure included regimen-related deaths (4), lack of response (10), or tumour progression (20) which occurred at a median of 5 months (1-22) post-ABMT and usually at previous sites of involvement. Response to salvage therapy pre-ABMT, a reflection of a tumour's biological behaviour, was the most important predictor of good outcome post-ABMT. This study confirms that a significant number of patients with recurrent NHL can achieve prolonged disease-free survival after ABMT.

Flow cytometry method for the analysis of membrane-associated human chorionic gonadotropin, its subunits, and fragments on human cancer cells.

A quantitative flow cytometry method for the analysis of membrane-associated human chorionic gonadotropin (hCG), its subunits, and fragments on human cancer cells was developed using a double-antibody reaction; a flow cytometry with a 2-W argon laser, standard settings, and filters for fluorescein isothiocyanate use; commercially available software; and the ectopic hCG producer CCL 2 HeLa cells from the American Type Culture Collection (ATCC) as a cell control to standardize the reagents and for overall quality control. Twenty-two monoclonal antibodies (MoAb) and immunoglobulin G fractions from three rabbit polyclonal antisera were tested for effects of antibody concentration (titration), reproducibility at different levels of epitope expression, and variability of epitope expression to select appropriate primary antibodies. Based on the results of the various tests, three polyclonal immunoglobulin G antibodies and a panel of nine MoAb directed to epitopes located in five different regions on the hCG molecule were selected as first antibodies. Their specificity was determined by using two unrelated MoAb of the same isotype at the same concentration to replace the primary MoAb and by a competition experiment. The unrelated MoAb also were used for the selection of the appropriate control fluorescence profile needed for the software. The unique characteristics of this method were: the use of living cells, standardized reagents, internal and external quality control, and the highest sensitivity, which could detect as few as 10(3) molecules of fluorochrome per cell. Serial analyses of the ATCC CCL 2 HeLa cells and two of its variants and of the eutopic hCG producer JEG-3 choriocarcinoma cells revealed the expression of membrane-associated epitopes of intact hCG, its subunits, and fragments by a high percentage of the cells, indicating that the expression of these sialoglycoproteins by these two different types of cancer cells is a common phenotypic characteristic.

Expression of membrane-associated human chorionic gonadotropin, its subunits, and fragments by cultured human cancer cells.

The expression of human chorionic gonadotropin (hCG), its subunits, and fragments on the cell membrane of cultured human cancer cells was investigated using a flow cytometric method. This method uses living cells; a double-antibody reaction; a flow cytometer with an argon laser, standard settings, and filters for fluorescein isothiocyanate; commercially available software; the American Type Culture Collection (ATCC) CCL 2 HeLa cell line as cell control and overall quality control; polyclonal rabbit antisera raised against the hCG dimer, its alpha subunit (hCG alpha), and its beta subunit (hCG beta); and a panel of monoclonal antibodies (MoAb) recognizing different epitopes on the intact hCG molecule, its subunits, and fragments. The purified immunoglobulin G fractions from the polyclonal antisera were used to estimate the total expression of the membrane-associated glycoproteins; the MoAb were used to detect the expression of epitopes of the hCG dimer, its subunits, and fragments. The results of the analyses done on cells from 74 established cancer cell lines of different types and origins (including 52 carcinomas, 10 sarcomas, 4 leukemias, 6 lymphomas, and 2 retinoblastomas) showed variable degrees of reactivity in a great percentage of cells in all cell lines studied with MoAb directed against different conformational epitopes of intact hCG (hCG-holo), hCG beta, hCG beta-free, the carboxy terminal peptide (CTP) of hCG beta, and an epitope of hCG alpha. The expression of the membrane-associated epitopes of hCG and its subunits was found to be a phenotypic marker characteristic of all evaluated cultured human cancer cell lines, irrespective of their type or origin. There were, however, quantitative and qualitative differences in the expression of the different epitopes. Thus, hCG beta, free and as part of hCG-holo, recognized by the MoAb against hCG beta-CTP, was expressed by a high percentage of cells of most cell lines. There was great variability in the expression of hCG-holo, recognized by MoAb B109. For this reason some groups of cancers expressed larger amounts of incompetent hCG alpha and/or hCG beta than others. Cell lines derived from adenocarcinomas of the lung were the only exception to this general finding; the expression of small amounts of hCG-holo was caused by a low degree of hCG alpha synthesis.

Sequential paraformaldehyde and methanol fixation for simultaneous flow cytometric analysis of DNA, cell surface proteins, and intracellular proteins.

A cell fixation and permeabilization procedure consisting of sequential paraformaldehyde and methanol was evaluated and found suitable for concomitant flow cytometric quantification of total cellular DNA, immunofluorescence measurements of cell surface proteins, and immunofluorescence measurements of intracellular proteins. Paraformaldehyde/methanol-fixed cells exhibited significantly greater intracellular antitubulin immunofluorescence than cells fixed with paraformaldehyde or methanol alone (p less than 0.002) and significantly greater intracellular antitubulin immunofluorescence than cells fixed with methanol followed by paraformaldehyde (p less than 0.006). With paraformaldehyde/methanol fixation, cell morphology was well preserved and forward and right angle light scatter properties were sufficiently well maintained to permit gating on these parameters. Cell surface marker staining with fluorescent anti-leukocyte antibodies was unaffected by fixation with paraformaldehyde/methanol. Paraformaldehyde effects on the intensity of DNA staining with propidium iodide were dependent on paraformaldehyde concentration and fixation temperature; these effects were least pronounced at low paraformaldehyde concentrations (0.25% or less), and at temperatures lower than 37 degrees C. Paraformaldehyde fixation may result in differences in propidium iodide staining of DNA in some diploid cells, which may produce small spurious aneuploid peaks in normal peripheral blood leukocytes. Paraformaldehyde fixation also produces an apparent increase in the DNA index of aneuploid cell populations in comparison with methanol fixation, particularly when the DNA index exceeds 1.5. Occasionally, this paraformaldehyde fixation-induced effect is useful in identifying biologically distinct near-diploid subpopulations in tumors.

Alternated versus syncopated CHOP-PVB: two studies for the treatment of non-Hodgkin's lymphoma by the Southwest Oncology Group.

Based on a preliminary trial that suggested that CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone), and PVB (cisplatinum, vinblastine, bleomycin), are at least partially non-cross-resistant, the Southwest Oncology Group treated patients with unfavorable histology, non-Hodgkin's lymphoma with CHOP and PVB. In the first study, 76 eligible patients were given three courses of CHOP, with complete or partial responders receiving three courses of PVB followed by three further courses of CHOP. Nonresponders after the initial three cycles of CHOP, received six courses of PVB. In the second study, 154 eligible patients were treated with alternating cycles of the two drug regimens. The overall objective antitumor response (CR + PR) was 77% for the first study and 58% for the second. The complete remission rates were 48% and 38%, respectively. The overall survival for both studies is similar. These results are interpreted in terms of the Goldie-Coldman hypothesis.

Flow cytometric S fraction as a predictor of clinical outcome in cystosarcoma phyllodes.

Clinicopathologic characteristics were evaluated in 20 cases of cystosarcoma phyllodes in relation to clinical outcome. Flow cytometric DNA studies were carried out in 15 of these 20 cases. Stromal overgrowth and an infiltrating tumor border emerged as prominent histopathologic features that were associated with an unfavorable clinical outcome. Flow cytometric S fractions greater than 0.05 were associated with poor clinical outcome. There was no correlation between tumor ploidy and clinical outcome. There were no direct correlations between clinicopathologic features and flow cytometric measurements. Our data suggest that flow cytometric S fractions may be a useful predictor of clinical outcome in cystosarcoma phyllodes that can complement the traditional histologic analysis of these rare breast tumors.

m-BACOD treatment for intermediate- and high-grade malignant lymphomas: a Southwest Oncology Group phase II trial.

One hundred six eligible patients with advanced intermediate- or high-grade malignant lymphoma were treated with methotrexate with leucovorin rescue, bleomycin, doxorubicin, cyclophosphamide, vincristine, and dexamethasone (m-BACOD) in a Southwest Oncology Group phase II trial. Patients were stratified by estimated bone marrow reserve, and impaired marrow reserve patients received reduced doses of cyclophosphamide and doxorubicin. The complete remission rate for normal marrow reserve patients was 65%, while the complete remission rate for impaired marrow reserve patients was 29%. With a median follow-up period of 41 months, 64% of complete responders in the normal marrow group are disease-free 3 years after their response. Three-year survival is 61% in the normal marrow reserve group and is 29% in the impaired marrow reserve group. Eighty-seven percent of treatment courses were given in accordance with protocol dosing and schedule. For doxorubicin, relative dose intensities were 0.75 and 0.61 (normal and impaired marrow reserve arms, respectively), for cyclophosphamide, 0.76 and 0.61, and for methotrexate, 0.55 and 0.45. Serum lactic dehydrogenase (LDH) level was the only pretreatment characteristic found to have a significant effect on overall survival. Severe or greater toxicity occurred in 97% and 89% of the normal and impaired marrow reserve groups, respectively, with granulocytopenia the principal toxicity. Treatment-related fatalities occurred in 8% of patients. m-BACOD is an effective but toxic treatment program for intermediate- and high-grade malignant lymphomas.

Discrepancies between flow cytometric and cytogenetic studies in the detection of aneuploidy in human solid tumors.

Parallel flow cytometric (FCM) cell DNA studies and cytogenetic studies were performed on clinical samples from twenty human solid tumors of various types and on cell lines established in tissue culture from three of these tumors. Six of twenty clinical samples (30%) showed concordance between flow cytometry and cytogenetics with respect to the presence or absence of aneuploidy. Among the fourteen cases with discrepancies between the two methods, 8 (40% of all cases) showed hypodiploidy by cytogenetics and had diploid DNA histograms. Three cases (15%) had prominent discrete peaks in the triploid to tetraploid region by cytogenetics but had only barely discernible corresponding peaks in the DNA histogram. In two cases (10%) cytogenetic studies revealed diffuse aneuploidy. Cytogenetic studies demonstrated near-tetraploidy in three samples, but only one of these was detected by FCM; all three cases exhibited other numerical chromosomal abnormalities. In one case aneuploidy was demonstrated by FCM and not by cytogenetics. Among the tumor cell lines established in culture, the DNA Index was often higher than the cytogenetic index. Overall, 13/20 or 65% of patients with solid tumors in this study had numerical chromosomal abnormalities that were not detected by flow cytometry. Eleven of these patients had distant metastases at the time of tumor sampling, and nine of these died of their disease within 1-11 months of the time of study.

Pseudo-Gaucher cells in the bone marrow of a patient with Hodgkin's disease.

The authors studied an 18-year-old woman with stage IIIB nodular sclerosis Hodgkin's disease whose bone marrow contained abnormal storage cells that resembled Gaucher cells by light microscopic examination ("pseudo-Gaucher" cells). Electron microscopic examination revealed that these cells differed from true Gaucher cells and resembled storage cells previously described in chronic myelogenous leukemia. The patient's peripheral blood leukocyte beta-glucosidase and serum acid phosphatase levels were elevated, ruling out the diagnosis of inherited Gaucher's disease. After treatment with six monthly cycles of systemic chemotherapy (nitrogen mustard, vincristine, procarbazine, bleomycin, doxorubicin, and prednisone), all signs of Hodgkin's disease and pseudo-Gaucher cells disappeared. Repeat leukocyte beta-glucosidase and serum acid phosphatase levels were unchanged. The present case is unique with its documentation of classical enzyme patterns for beta-glucosidase and acid phosphatase and electron microscopic features. The authors postulate that pseudo-Gaucher cells result from excessive cell breakdown with an overload of available beta-glucosidase.

Malignant lymphoma, mixed cell type, diffuse.

This retrospective study of diffuse mixed (DM) cell lymphoma was undertaken as a collaborative study between the Repository Center for Lymphoma Clinical Studies and four cooperative oncology groups (CALGB, ECOG, SECSG, SWOG), and was based on 62 patients from the files of the Repository Center. We wanted to ascertain whether there were any significant clinical differences among the various morphological subtypes of this lymphoma. All patients were treated according to different protocols of the Cooperative Oncology Groups sponsored by the National Cancer Institute. In 16 patients (26%), the malignant lymphoma (ML) had morphological features consistent with follicular center cell origin (FCC); in 34 patients (55%), the ML did not have features of follicular center cell type (non-FCC), but had morphology described for peripheral T-cell-derived ML. In 8 of the patients (13%), no agreement could be reached by the 7 histopathologists who participated in the study, and these were classified as unresolved; the remaining 4 (6%) were unclassifiable. We compared the survival times of the 16 patients having the morphological features of the FCC subtype with the survival times of the 34 patients with the non-FCC subtype and found that patients with FCC lived longer (p = 0.07 Cox's regression). In the FCC group, all patients who had complete remissions (CR) were alive; however, their survival times were similar to those who had a partial or no response (p = 0.32). In contrast, in the non-FCC group, the median survival was 20 mo, and patients with a CR had a significantly longer survival than did incomplete responders (p = 0.003). According to these results the non-FCC diffuse mixed cell lymphoma appears to be a high-grade malignant lymphoma, whereas the FCC type is not.