Clinical spectrum of lymphoproliferative diseases

DNA flow cytometry of non-Hodgkin's lymphomas: correlation with cytologic grade and clinical relapse

In this prospective study, we correlated cytological grading and clinical follow-up of non-Hodgkin's lymphomas (NHL) with DNA flow cytometry (FCM) data from fine-needle aspiration biopsy (FNAB) material. FNAB was performed from 34 successive cases of NHL, and the aspirated material was analyzed by DNA FCM. Cytological subtyping and grading were done by modified Working Formulation. Cases were followed up for 2.5 yr, and cytological grading, clinical follow-up, and DNA FCM data were correlated. There were 8 cases of low, 14 intermediate, and 12 high-grade NHL. None of the cases of low-grade NHL showed DNA aneuploidy. Of the 8 DNA aneuploid cases, 5 were of intermediate and 3 were of high-grade NHL. Mean growth fraction (GF) of low-grade, intermediate-grade, and high-grade NHL was 6.1, 9.4, and 19.4, respectively. DNA aneuploidy was statistically significant (P < 0.05) between low- vs. intermediate- and high-grade NHL. Growth fraction was also statistically significant between low- vs. high-grade NHL. Six cases showed clinical recurrence, and one case died within 6 mo of diagnosis, due to widespread involvement of NHL. DNA aneuploidy and mean GF of recurrent and nonrecurrent cases were statistically significant (P < 0.05) irrespective of grading of NHL. DNA aneuploidy and GF are not well-correlated with morphological grading (by the Working Formulation). However, these two criteria are important for assessment of early clinical relapse of NHL.

B-cell clonality and infection with Helicobacter pylori: implications for development of gastric lymphoma

BACKGROUND

Although Helicobacter pylori has been implicated in the pathogenesis of gastric mucosa associated lymphoid tissue (MALT) and MALT lymphoma, it is not known how it may trigger these lesions and whether there is an identifiable pre-neoplastic stage.

AIMS

To investigate the relation between MALT, H pylori infection, and B-cell clonality (a potential marker of pre-neoplastic lesions).

PATIENTS

141 subjects with simple dyspepsia.

METHODS

Gastric biopsy specimens from all patients were examined for MALT and H pylori. Of these, 25 consecutive MALT positive specimens were scored for features of MALT lymphoma and VDJ clonality studied by polymerase chain reaction.

RESULTS

Overall, prevalence was 62% for H pylori and 46% for MALT. VDJ clonality was frequent in the sub-group studied (nine of 25), mostly associated with lymphoid follicles (eight of nine or 89%), and with a high scoring for MALT lymphoma. VDJ clonality was equally frequent in patients with and without H pylori (seven of 20 and two of five or 35% and 40% respectively).

CONCLUSIONS

B-cell clonality is unexpectedly common in subjects with simple dyspepsia and MALT raising clinical management questions. These findings also suggest that the cascade MALT formation--B-cell clonality--MALT lymphoma may not be uniquely associated with H pylori infection.

The follicular non-Hodgkin's lymphomas--I. The possibility of cure

The follicular lymphomas pursue an indolent course in many patients. Long-term follow-up in large series is therefore necessary to establish whether cure is taking place, and if so, at what stage in the dissemination of the disease process it becomes unlikely. The time to, and site of relapse, together with its impact on survival has been studied in 398 patients entered into the British National Lymphoma Investigation limited and disseminated disease trials between 1974 and 1980. Relapse data were compared with various models to obtain maximum likelihood estimates of the proportions permanently remaining relapse-free following treatment. Long-term relapse-free survival was observed in 54.8 +/- 14.9% (95% CI) of patients at 15 years with Ann Arbor stage I disease, 29.2 +/- 13.6% in patients with stage II disease, 18.1 +/- 6.6% with stage III and 13.0 +/- 5.9% with IV disease. Relapse time-course data for all trial arms conform closely to lognormal distributions allowing maximum likelihood estimates of proportions remaining permanently relapse-free to be derived. Using this methodology, over a quarter of patients treated with involved radiotherapy alone or radiotherapy plus 6 months of chlorambucil in the limited disease (Ann Arbor stage I and II) trial are unlikely to relapse at any time in the future. Over 10% of patients treated in the disseminated disease trials with disease classified as Ann Arbor stage III are also statistically unlikely to relapse. The finding that a proportion of patients is statistically unlikely to experience a clinically obvious relapse is consistent with clinical cure. It is especially interesting that a small proportion of patients with disseminated disease and treated by chemotherapy have fallen into this category, but additional data are required to know at what point statistical cure becomes unlikely. Whether "clinical cure" is the same as "pathological cure" in this disease remains uncertain.

The follicular non-Hodgkin's lymphomas--II. Prognostic factors: what do they mean?

The Ann Arbor staging classification has long been recognised to have shortcomings when used to stage the follicular lymphomas. To date, the identification of important prognostic variables has not succeeded in producing a superior staging classification that reflects the stages of dissemination of these processes in a way that can be used in the testing of new therapeutic strategies. A fresh look is taken at these factors. Data from 398 patients entered into the British National Lymphoma Investigation trials between 1974 and 1980, were analysed to evaluate the performance of the Ann Arbor staging classification. Multiple regression and proportional hazards techniques were used to determine what factors independently influence response to initial treatment, the durability of that response and ultimate survival, and to isolate factors that relate to disease progression from those that have other mechanisms of action. The Ann Arbor staging classification fared poorly, minimally separating relapse-free and cause-specific survival probabilities in patients with the largest staging groupings, III and IV. Significant prognostic heterogeneity was seen in both of these stage groupings, with 22% of patients with stage IV disease on the basis of marrow involvement having slightly better outcomes than patients with stage III disease. Significant differences in outcome were also observed between patients of different age and sex in each Ann Arbor stage grouping. Increasing number of lymph node regions involved, constitutional symptoms, the presence of splenomegaly and increasing age were observed to have powerfully independent adverse influence on probability of complete response to treatment and cause-specific survival. The evolution of the follicular lymphomas is reflected at the clinical level by an increase in the number of lymph node regions involved and splenomegaly. Simple classifications based on simple counts of lymph node regions involved and splenomegaly are more successful than the Ann Arbor staging classification in subdividing the series into patient subgroups that, regardless of gender or age, experience significantly different probabilities of responding completely to therapy and, as a consequence, relapse-free and cause-specific survival expectations. The definition of poor prognosis in subgroups may be of value in selecting patients for newer and more intensive therapeutic approaches.

B-cell follicular lymphomas: clinical and biological characteristics

Seventy cases of follicular B-cell lymphomas were studied: 37 cases derived from the follicular centre [27 centroblastic-centrocytic (CB-CC) and 10 centroblastic (CB)] and 33 from the mantle zone [mantle-cell lymphoma (ML)]. Presenting features as well as response to therapy, time free of symptoms and survival were reviewed. All the cases were diagnosed and classified with routine and immunohistochemistry methods. In 61 cases tumors were studied with specific markers in a CAS-200 Image Analyser. Flow cytometry (FCM) was also done and correlated with proliferative-values and survival. A minor aggressive course of CB-CC and ML was demonstrated, with ML being the most benign form (lower proliferation rate and longest survival). Ploidy did not correlate with histological subtypes, survival or response to therapy. These results confirm the utility of biodynamic studies in lymphoid neoplasias.

Higher proliferative response in B-chronic lymphocytic leukemia (B-CLL) as compared to B-monoclonal lymphocytosis of undetermined significance (B-MLUS) after stimulation with Staphylococcus aureus and anti-CD40 monoclonal antibodies

B-CLL is a malignant monoclonal B-cell disorder and B-MLUS is the benign counterpart. The proliferative response and the capacity to secrete IgM was measured in B-CLL and B-MLUS, respectively, and compared to normal B-cells. SAC and a mAb against CD40 were used as stimulatory agents. No cell population responded to anti-CD40 mAb alone. SAC only induced a high DNA synthesis rate in normal B-cells as well as in B-CLL cells, although the magnitude was three-fold lower and delayed for about 48 h in B-CLL. B-MLUS cells did not proliferate in response to SAC. The combination of anti-CD40 and SAC enhanced the proliferative capacity of normal B-cells and produced a more rapid response in B-CLL. B-MLUS cells were not activated. Normal B-cells and B-MLUS did not secrete IgM after SAC stimulation, while B-CLL cells had a continuous increase in the IgM production during a 6-day culture period. The higher proliferative capacity of B-CLL cells compared with B-MLUS cells may be explained by an increased expression of activation molecules e.g. receptors for various cytokines and growth factors. Moreover, the inertness and inability of B-MLUS cells in comparison to normal B- and B-CLL cells to respond to powerful activation signals might indicate an intrinsic defect of B-MLUS cells in the signal transduction leading to a block of mitosis and a benign course of the disease.

Prognostic value of cytophotometric analysis of DNA in lymph node aspirates from patients with non-Hodgkin's lymphoma

To classify cases of non-Hodgkin's lymphoma in terms of expected clinical behaviour and survival, kinetic parameters measured by cytophotometry were assessed in 62 patients between 1978 and 1987. The influence of the number of cells with increased DNA content (more than 2N) on survival was evaluated. Analyses were carried out on the small samples obtained by needle aspiration biopsy of lymph nodes before treatment, using microdensitometry and Feulgen staining. Patients whose lymphomas contained less than 6% of cells with increased DNA content had a mean survival of 81.3 months and those whose lymphomas contained 6% or more of such cells had a mean survival of 18.5 months. A significant difference in survival using the same criteria was also noticed for patients with both low grade lymphomas and those with intermediate and high grade lymphomas. It is concluded that cytophotometric analysis of lymph node aspirates is of prognostic value in the initial assessment of non-Hodgkin's lymphoma.

Gastric small lymphocytic proliferation with immunoglobulin gene rearrangement in pseudolymphoma versus lymphoma

The nature of gastric infiltrates consisting primarily of benign-appearing small lymphocytes is at present a controversial issue. Earlier reports of gastric lymphoma developing in gastric pseudolymphoma and more recent immunohistochemical studies demonstrating monoclonal B-cell populations in pseudolymphoma suggest that at least some cases represent low-grade lymphomas or clonal precursor lesions that may develop into lymphoma. Observations of a small lymphocytic infiltrate arising in the region of a gastric ulcer that lacked definitive morphologic evidence of malignancy (lymphoma) but was clearly a monoclonal B-cell proliferation by immunohistochemical and gene rearrangement studies support the notion that some gastric lymphoproliferative lesions that histologically have been called pseudolymphomas may include one or more clonal lymphoid expansions. A histopathologic/molecular model suggesting a potential pathway for the development of morphologically recognizable lymphoma from benign-appearing small lymphocytic infiltrates is presented, and the concept that for a variety of lymphoid proliferations clonality and malignancy may not be synonymous is discussed.

Bone marrow and blood involvement by non-Hodgkin's lymphoma: a study of clinicopathologic correlations and prognostic significance in relationship to the Working Formulation

In a series of 172 patients with non-Hodgkin's lymphoma (NHL) classified according to the Working Formulation (WF) the overall incidence of bone marrow infiltration (BM+) at diagnosis was 39%: 59% for low-grade (LGML), 30% for intermediate-grade (IGML), and 25% for high-grade malignant lymphomas (HGML). The features most significantly correlated with the presence of BM+ were a low grade of histological malignancy, the degree of splenomegaly and high values of LDH, while those correlated with the extent of BM+ were a non-focal pattern of BM disease, the presence of blood involvement at diagnosis, and the degree of BM fibrosis. Blood involvement was detected at diagnosis in 13% of patients, and a further 16% developed a leukemic phase during the course of the disease. Blood involvement correlated significantly with splenomegaly, bulky disease, advanced clinical stage, and extent of BM+. The presence of BM infiltration 'per se' at diagnosis did not significantly affect prognosis. However, the extent of BM disease was correlated with a poorer outcome in IGML and HGML patients. Regarding peripheral blood involvement, in LGML patients only late leukemic conversions were significantly associated with a worse prognosis. In patients with IGML and HGML, either initial or subsequent blood involvement was correlated with significantly poorer outcome.

Higher T-cell imbalance and growth factor receptor expression in B-cell chronic lymphocytic leukemia (B-CLL) as compared to monoclonal B-cell lymphocytosis of undetermined significance (B-MLUS)

The surface marker phenotype of lymphocytes derived from 12 patients with B-CLL was compared to that of lymphocytes from 10 patients with an other monoclonal but clinical benign form of B-cell proliferative disorder termed monoclonal B-cell lymphocytosis of undetermined significance (B-MLUS). A panel of well characterized monoclonal antibodies was used for the surface marker determinations. The mean total number of B cells (CD20) was 8.5 x 10(9)/1 in B-MLUS as compared to 44 x 10(9)/1 in B-CLL (p less than 0.001). B-CLL had a greater imbalance in T-cell subpopulations than B-MLUS and healthy controls. Total numbers of CD3+, CD8+ cells as well as cells expressing the NK-related antigens (CD16, Leu-7) and IL-2 receptor (CD25) bearing lymphocytes were statistically significant higher in B-CLL than in B-MLUS. Analyses of B-cell enriched populations showed that B-CLL represented B cells of an early maturation stage, whereas B cells from B-MLUS were more mature as judged by the loss of the CD21 surface marker. A larger fraction of B cells in B-CLL compared to B-MLUS exhibited a higher activation stage as revealed by the expression of the CD21, CD25 and CD35 structures as well as the FMC7 antigen.

Results of laparotomy in immunoproliferative small intestinal disease

Immunoproliferative small intestinal diseases (IPSID), previously known as Mediterranean Lymphomas, constitute more than 60% of the non-Burkitt's small intestinal lymphomas in Tunisia. A multidisciplinary study of IPSID was undertaken by the Tunisian/French Lymphoma Study Group in 1980 to reach a better understanding of the two subgroups of the disease: secreting IPSID (essentially alpha-chain disease [ACD]); and nonsecreting IPSID (NS-IPSID) (extensive small intestinal lymphomas without gammopathy). The results of initial exploratory laparotomy performed in 38 cases of IPSID (17 ACD and 21 NS-IPSID) are described here, and show notable similarities between the two groups: the extensive pattern of the abnormal cell infiltrate along the major part of the small intestine; frequent and extensive involvement of the mesenteric lymph nodes; the existence of several degrees of severity in small intestinal mesenteric lymph nodes; and other intraabdominal organ involvement. Certain differences also were observed: the relatively high degree of tropism of the NS-IPSID towards the gastric mucosa which was absent in the ACD of this series; and the more frequent involvement of the entire length of the small bowel in ACD. In spite of these discrete differences, the IPSID form a homogeneous group which is definitely distinguishable from the segmentary small intestinal lymphomas known as Western-type, and which account for approximately one third of our non-Burkitt's small bowel lymphomas.

Clinical and immunological findings in large B-cell chronic lymphocytic leukemia

In order to define the characteristics of B-CLL cases in which the predominant cell population is composed of large lymphocytes, we studied 97 patients with B-CLL, comparing the cell morphological features with the clinical and biological findings and the immunological phenotype of the proliferating cells. Multivariant analysis showed that there were three significantly different morphological groups: Typical CLL, large lymphocyte CLL (LLL), and CLL with prolymphocytes (CLL/PL). The LLL group showed a greater incidence of lymphadenopathies (P less than 0.05) and higher percentages of both mu + delta + cells (P less than 0.01) and Fmc/7+ cells (P less than 0.001) than in typical CLL. The main differences between LLL and CLL/PL were the peripheral blood lymphocyte count and the percentage of Fmc/7+ cells (P less than 0.002)--both higher in the CLL/PL group--and the percentage of mouse rosette-forming cells (P less than 0.01)--lower in CLL/PL. Further studies including functional assays and survival analyses could contribute to elucidating whether these groups are different entities or a single disease with marked heterogeneity.

Clinicopathologic and immunologic characteristics of non-Hodgkin's lymphomas presenting in the orbit. A report of eight cases

Of 325 consecutive cases of non-Hodgkin's malignant lymphomas, 8 patients (2.4%) showed orbital presentation. The clinicopathologic and immunologic analysis of the eight patients revealed characteristic biologic features. Despite the apparently isolated orbital presentation, all cases had subclinical systemic disease. Seven of the eight cases exhibited lymphoplasmacytic/cytoid features, with concurrent type II cryoglobulinemia in five of them. In addition, during their clinical course, five patients showed single or multiple subcutaneous nodules with the same histologic and immunologic pattern as the orbital tumor. This study demonstrates that most orbital lymphomas share particular clinicopathologic and immunologic features, suggesting an origin from a B-cell subset with preferential homing to orbital tissues and subcutis.

Gastric pseudolymphoma with monotypic cytoplasmic immunoglobulin

Two cases of hyperplastic lymphoid lesion of the stomach with cytoplasmic immunoglobulin of monotypic pattern are presented. Both patients were young, and the postgastrectomy course was uneventful for 38 and 76 months, respectively. The lesion had been diagnosed as pseudolymphoma based on the presence of hyperplastic follicles with germinal center and mixed infiltration of plasma cells and mature lymphocytes with no significant cytologic atypia. However, the immunoperoxidase method showed monotypic cytoplasmic immunoglobulin; lambda/IgM in one case and lambda/IgG in the other. The staining pattern of germinal centers was also monotypic in one, but polytypic in the other. These cases suggest the presence of monoclonal but reactive lymphoid hyperplasia, i.e., monoclonal-type pseudolymphoma in the stomach. On the other hand, this type of lesion has to be carefully followed for the possible development of malignant lymphoma.

Acute undifferentiated leukemia: induction of partial differentiation by phorbol ester

Expression of lineage-associated surface antigens, was studied in 7 patients with acute undifferentiated leukemia (AUL), 3 patients with acute myeloid leukemia (AML), 4 patients with acute lymphoid leukemia (ALL) and bone marrow from 2 healthy donors, before and after exposure to the differentiating agent 12-O-tetradecanoylphorbol-13-acetate (TPA). The surface antigens were identified by monoclonal antibodies (My4, My8, My9, MO1, B1, CALLA, T11) and formation of EA and EAC rosettes. Adherence to plastic was also assessed. Cells from the AML patients responded to TPA with an increase in myeloid antigen positive cells and other markers of differentiation. Four of the AUL patients showed, also, a large increase in the fraction of cells expressing one or more myeloid markers, in correlation with formation of EAC rosettes. In contrast, the percentage of cells expressing myeloid antigens, did not increase in the 4 ALL patients, or in the normal donors. These findings confirm the heterogeneity of undifferentiated leukemias, and suggest the hypothesis that some AUL's can be induced to express markers of early myeloid cells.

Phenotypic characterization of acute leukemia with monoclonal antibodies using the microlymphocytotoxicity assay

Surface antigens of lymphoblasts from 56 pediatric ALL patients were studied with a set of complement fixing monoclonal antibodies. This group of lymphoblasts was comprised of 22 T-cell ALL, 22 CALLA+ Ia+ ALL and 12 non-T-non-B, CALLA- Ia+ ALL. For comparison, two adult T-cell CLL and six B-cell CLL were also studied. It was found that by using the microlymphocytotoxicity technique, the lymphoblasts can be assigned their immunophenotype and thus be classified into their respective lineage and stage of differentiation. In the samples tested, concordant reactivity was observed when FACS fluorescence profile was compared with that of microlymphocytotoxicity suggesting that the latter can be used especially when qualitative estimates are required.

The incidence of B cell leukaemia and lymphopenia in B cell neoplasia in adults: a study using the Kiel classification of non-Hodgkin's lymphoma

The incidence of B cell leukaemia in 186 consecutive untreated patients with histologically defined B cell neoplasms is described. The lymphomas were classified by the Kiel convention. B cell leukaemia in the context of this paper refers to the situation where a neoplastic clone of B cells in the blood greatly outnumbers normal blood B cells. It is defined as an absolute blood B cell count greater than 0.75 X 10(9)1(-1) where either greater than 90% B cells express kappa immunoglobulin light chains or greater than 80% express lambda light chains. This was found in several patients where the total blood lymphocyte count was within normal limits. All patients with diffuse lymphocytic lymphoma with the histological appearances of B cell chronic lymphocytic leukaemia (ML-BCLL) were found to have B cell leukaemia. However, more than half these patients had blood B cell counts less than 10 X 10(9)1(-1). B cell leukaemia was also a feature in approximately 33% of patients with follicle centre cell tumours and 33% of those with lymphoplasmacytoid tumours. B cell leukaemia was not detected in 34/35 patients with myelomatosis. The 35th patient had plasma cell leukaemia. Only 3/22 patients with high grade lymphoma had B cell leukaemia. In the three principal tumour types associated with B cell leukaemia mu + delta was the most common immunoglobulin heavy chain phenotype. Spontaneous mouse red cell rosette formation also characterised leukaemic B cells in these three groups but high proportions of mouse rosetting cells were seen only in association with ML-BCLL. None of 4 cases of prolymphocytic leukaemia showed mouse red cell rosetting. HLA-DR alpha chain was found on the leukaemic cells of all patients except one with ML-BCLL. B cell lymphopenia was a frequent finding in all histological groups in those patients who did not have B cell leukaemia.

Normal equivalent cells of B cell malignancies: analysis with monoclonal antibodies

Immunoglobulin heavy chain expression and reactivity of monoclonal antibodies RFA-1, -2, -3, -4 and OKT10 discriminate between majority B lymphocyte populations in the bone marrow and in peripheral lymphoid organs. In this study normal tissues and various B cell malignancies were studied in cell suspensions and tissue sections. Pre-B acute lymphoblastic leukaemia and multiple myeloma apparently reflect the phenotypes on normal B lineage cells of the bone marrow, while centroblastic-centrocytic lymphoma, B chronic lymphoid leukaemia (CLL) and prolymphocytic leukaemia (PLL) show the characteristics of distinct peripheral B lymphoid subsets found at different sites in the lymphoid tissue. These 'normal equivalent' cells are centroblasts and centrocytes in the germinal centre. CLL-like cells at the edge of the germinal centre (a minority population) and strongly Ig positive cells in the lymphocyte corona. Malignant cells in macroglobulinaemia are apparently more closely related to PLL and the corresponding normal peripheral B cells (in the corona) than to myeloma cells or the equivalent normal plasma cells in the bone marrow.

Immunohistologic studies of cytoplasmic immunoglobulins in rheumatic diseases including two patients with monoclonal patterns and subsequent lymphoma

Tissue specimens from five patients with rheumatic disease who developed lymphadenopathy were studied by an immunoperoxidase method; available biopsy material was examined for cytoplasmic immunoglobulin determinants. Three patients had follicular hyperplasia of lymph nodes with polyclonal patterns. Two patients with Sjogren's syndrome had monoclonal patterns; both of these patients subsequently developed lymphoma with similar monoclonal patterns. Implications of the monoclonal patterns with regard to the biology of these lymphoproliferative disorders are discussed.

Mechanism of total body irradiation in lymphoma. A hypothesis

A previously proposed theory of lymphoma pathogenesis is discussed and extended to assist in the formulation of a hypothesis for the mechanism of low dose systemic irradiation of lymphoma. It is proposed that masses of non-Hodgkin's lymphoma may not necessarily be truly autonomous neoplasms, and that low dose total body irradiation may be effective in such cases through a cytotoxic action on more radiation sensitive precursor cells in the peripheral blood and bone marrow.

Focal lymphoid hyperplasia of the stomach preceding gastric lymphoma: case report and review of the literature

A case is reported in which focal lymphoid hyperplasia (pseudolymphoma) of the stomach preceded by 45 months the development of gastric diffuse lymphocytic lymphoma. Review of the literature discloses only two similar cases reported with satisfactory histopathologic documentation. Analogous cases, in other anatomic sites, of an apparent association between benign and malignant lymphoid lesions are reviewed. The cases suggest that occasionally lymphoid hyperplasia of the stomach may precede lymphoma. Lymphoid hyperplasia is not yet considered a consistent precursor of lymphoma.

Spontaneous immunoglobulin changes in human plasma-cell dyscrasia

A series of spontaneous changes affecting the nature of the immunoglobulin secretion of plasma cels is described in a patient initially diagnosed as IgG lambda benign monoclonal gammopathy. After several years a slight increase in the amount of serum monoclonal immunoglobulin occurred; shortly thereafter an aggressive form of multiple myeloma was diagnosed. Unexpectedly a rapid spontaneous decrease of the monoclonal immunoglobulin, accompanied by the appearance in the serum of increasing quantities of a complex containing intact lambda light chains, then occurred. Concomitantly a fragment of the corresponding free light chain was was detected in the urine. A parallel is drawn between the facts observed in this patient and in an animal model recently proposed to explain the different types of structural immunoglobulin abnormalities in multiple myeloma.

Abscopal regression in lymphoma: a mechanism in common with total body irradiation?

The hospital records of 895 patients presenting to this centre with a diagnosis of Hodgkin's or non-Hodgkin's lymphoma have been reviewed. In the records of 26 patients there was evidence for or against the occurrence of abscopal regression with radiotherapy. Attention is drawn to inevitable inaccuracy in a retrospective study of this type. Evidence of abscopal regression was seen in the records of 10 patients, four with Hodgkin's and six with non-Hodgkin's lymphoma. It appears to be associated with a more favourable prognosis in patients with non-Hodgkin's lymphoma. It is suggested that this phenomenon is elicitable in more patients than is commonly recognised, and that together with response to low dose total body irradiation, could be explained by radiation damage to normal lymphocytes.

The physiopathological significance of benign monoclonal gammopathy: a study of 64 cases

Sixty-four patients with monoclonal protein in serum but initially without evidence of multiple myeloma, macroglobulinaemia, amyloidosis or lymphoma, were studied. Fifty patients (78%) were observed for a period of exceeding 3 years. Based on the follow-up data the patients were classified into the following four groups: Group 1 = patients with transient monoclonal gammopathy: 4 . 7%; Group 2 = patients without significant increase in monoclonal serum protein: 75%; Group 3 = patients with more than 50% increase in monoclonal serum protein: 14 . 1%; Group 4 = patients in whom multiple myeloma developed: 6 . 2%. The mean interval from discovery of the serum monoclonal protein to evolution to multiple myeloma was 61 months. Retrospective analysis of age, sex, blood count, bone marrow picture, antigenic type and size of serum monoclonal proteins, presence of small amounts of homogeneous light chain in the urine, serum albumin level, levels of residual immunoglobulins, did not help to distinguish initially the patients in whom the monoclonal gammopathy evolved to multiple myeloma from patients in whom the disease remained benign and stable. The evolution to multiple myeloma had occurred abruptly after long periods of stable condition; and until this progression the follow-up data were similar to the patients with benign disease. The possible physiopathology of occurrence and evolution of benign monoclonal gammopathy is discussed.

B-prolymphocytic leukaemia--a mantle zone lymphoma?

A case of prolymphocytic lymphoma/leukaemia (PL) sensu Galton in a 32-year-old man is presented. The leucocyte count was 19.0 x 10(9)/1 at presentation and tartrate resistent acid phosphatase was present in most prolymphocytes. Immunological investigation of prolymphocytes from lymph nodes, spleen and peripheral blood revealed the surface marker phenotype: SmIg + (mu, (delta), lambda), IgG-Fc-receptor +, C3-receptor +. The prolymphocytes from lymph nodes and spleen were C3-receptor + in a high percentage, while only a few were IgG-Fc-receptor +. This proportion was reversed in the blood prolymphocytes. The histology of lymph nodes was unique and strongly suggested a preferential involvement (homing phenomenon) of the mantle zone of the lymphatic follicle. These results may indicate that emission of prolymphocytes from lymph nodes to circulation involves a change of surface receptors. It is finally suggested to consider the diagnosis of not only hairy-cell leukaemia but also PL in the case of tartrate resistent acid phosphatase-positive lymphoma/leukaemia.

Clinico-pathologic correlation in non-Hodgkin's lymphoma. III. Biologic significance of a modified Lukes and Collins classification

With a modified Lukes & Collins classification of non-Hodgkin's lymphomas applied retrospectively to a patient series the biologic and clinical implications of some microscopic features were analysed. It was found that, based on this classification, proliferation, dissemination and differentiation could be explained in a comprehensible way.