Detection Of Marrow Involvement Research Articles

FDG PET/CT may replace bone marrow biopsy for the evaluation of bone marrow involvement in selected mature T- and natural killer-cell lymphomas: A meta-analysis

PurposeTo systematically determine the role of FDG PET/CT for the diagnosis of bone marrow involvement in mature T- and natural killer (NK)-cell lymphomas. MethodsThe PubMed, Embase and Cochrane Library databases were searched to identify eligible studies. Data extraction and quality assessment were independently conducted. Then, pooled diagnostic performance with the 95 % confidence interval (CI) was calculated and further analyzed based on different interpretation criteria, tumor type and stage. ResultsFifteen studies were eventually included for quantitative analysis. Overall, the methodological quality of included studies was acceptable. For detecting bone marrow involvement, FDG PET/CT achieved a poor sensitivity of 0.62 (95 % CI, 0.48–0.71) and a reasonable specificity of 0.92 (95 % CI, 0.87–0.96). Similar performance was observed for the specific type of extranodal NK/T‐cell lymphoma (ENKTCL). In early-stage patients revealed by PET/CT, extremely small proportion (2/777) showed positive bone marrow biopsy, especially for the specific type of ENKTCL, whereas in advanced-stage patients, the specificity of FDG PET/CT dropped to 0.77 (95 % CI, 0.72–0.82). Regarding the interpretation, both diffuse and focal increased uptake patterns as positivity may result in increased sensitivity but decreased specificity compared with focal pattern alone as positivity. ConclusionsFDG PET/CT demonstrated excellent negative predictive value for detecting marrow involvement in early-stage patients with mature T- and NK-cell lymphomas, especially the ENKTCL. Conversely, FDG PET/CT showed poor performance for the diagnosis of bone marrow involvement in advanced-stage patients.

Role of 2-(fluorine-18) Fluoro-2-deoxy-D-glucose Positron Emission Tomography/Computed Tomography in Initial Staging and Bone Marrow Involvement Prediction in Patients with Newly Diagnosed Lymphoma in Correlation with Bone Marrow Study.

Lymphoma is a common malignant proliferative disease in which bone marrow infiltration will upstage the disease and thus affect prognosis of the disease. As of now bone marrow biopsy is considered as a reference standard to find out bone marrow involvement in lymphoma. Performing an invasive and painful intervention in all newly diagnosed lymphoma patients is controversial. PET-CT is a non-invasive technique that gives functional information about the cells using the glucose metabolism. It can detect early bone marrow and extra medullary organ involvement which can lead to restaging of the disease. These advantages make PET-CT a valuable adjunct in diagnosis of lymphoma. Our study aims to evaluate the usefulness of 18 F-FDG PET-CT, a non-invasive, semi quantitative whole body imaging technique for detection of early bone marrow and extra medullary organ involvement in lymphoma patients which in turn can obviate the need for bone marrow study (BMS). The primary objective of study is to categorise FDG uptake in bone marrow as diffuse /unifocal /multifocal / no uptake and to correlate pattern of FDG uptake to bone marrow study. Our study also assesses the role of FDG PET/CT in staging of lymphoma. Thirty patients with newly diagnosed lymphoma in the age group 18 to 75 years of both sexes within 3 months of diagnosis and who have not been started on any treatment was included in the study. Marrow uptake on FDG PET/CT has been categorized as diffuse, unifocal, multifocal and no uptake. Agreement between bone marrow study and FDG PET/CT has been assessed by reliability analysis using Cohen's kappa. Sensitivity, specificity, PPV, NPV of PET/CT in detecting marrow involvement have been calculated. The sensitivity, specificity, PPV, NPV and accuracy of 18 F-FDG PET-CT in detecting marrow involvement of lymphoma cases are 86.6%, 77.7%, 68.4%, 91.3% and 80.9% respectively. 18 F-FDG PET-CT detected bone marrow involvement in 86.6% (13 out of 15 total positive cases) cases of lymphoma which included both HL and NHL. Reliability analysis using Cohen's kappa is used to test the agreement between bone marrow study and 18F-FDG PET/CT. k value of 0.6 was obtained which showed a moderate agreement between bone marrow study and 18F-FDG PET/CT in marrow assessment. 18F-FDG PET/CT is a highly sensitive imaging modality which can pick up extra-nodal organ and BMI in patients with lymphoma and can upstage the disease and alter treatment strategies. PET-CT cannot completely replace the bone marrow study. However, being an invasive painful procedure, BMB can be avoided in cases with unifocal or multifocal marrow involvement on PET-CT.

Role of high acquisition flow cytometry in the detection of marrow involvement in patients with extramedullary B cell non-Hodgkins lymphoma: a comparison with marrow aspirate cytology, trephine biopsy, and PET

Detection of marrow infiltration is crucial in extramedullary B cell non-Hodgkin lymphoma (B-NHL). We studied the efficiency of high acquisition flow cytometry (FCM) in detecting marrow involvement in B-NHL patients and compared its performance with marrow aspiration (BMA) cytology, marrow biopsy (BMB), and positron emission tomography (PET). No case with marrow infiltration was found to be BMB positive and FCM negative. BMA cytology showed poor sensitivity and specificity. Only 50% of FCM positive cases showed evidence of marrow involvement by PET. Neither the nature of lymphoma nor the burden of the marrow disease showed a correlation with PET positivity. Four cases that were positive only by PET had findings in areas other than the iliac region. We found more cogent and convincing results with high event acquisition in FCM. This study shows that a combination of PET and FCM with high event acquisition is the best way for assessing marrow involvement in B-NHL cases.

FDG PETCT for assessing marrow involvement at staging pediatric nonhematological round cell malignancies.

Bone and lung are the common sites of metastasis in pediatric round cell tumors and its presence indicates poor outcomes. Staging workup for these malignancies thus includes bone marrow biopsy (BMB) along with evaluation of thorax, and tissue analysis for N MYCN status in neuroblastoma. BMB is an invasive procedure requiring general anesthesia with known disadvantages.With an aim of avoiding an invasive BMB a study was taken up to evaluate efficacy of FDG PET CT in detecting marrow involvement in neuroblastoma and rhabdomyosarcoma at staging. Prospective observational study evaluated 83 newly diagnosed treatment naïve patients of neuroblastoma (n = 43) and rhabdomyosarcoma (n = 42) who underwent conventional imaging of PETCT with CECT of local region along with a CT thorax and BMB (both iliac crest) done within 1 week. Findings of FDG PETCT were compared with bone marrow histology and accuracy parameters were calculated. The overall sensitivity, specificity, accuracy, positive-predictive value (PPV), negative-predictive value (NPV) of FDG PETCT for detection of marrow disease was 100%, 86.1%, 89.4%. 68.9% and 100%, respectively. Subset analysis showed sensitivity, specificity, PPV and NPV of 100%, 66%, 71.4% and 100%, respectively, for neuroblastoma, with rhabdomyosarcoma patients having few events NPV of 100% accuracy of 97.6%. FDG PETCT with sensitivity and NPV of 100% can be considered as a first stop imaging and biopsy can be avoided in patients with a negative scan.

Role of 18F-FDG-PET/CT in the staging of metastatic rhabdomyosarcoma: a report from the European paediatric Soft tissue sarcoma Study Group

BackgroundInitial staging of rhabdomyosarcoma is crucial for prognosis and to tailor the treatment. The standard radiology workup (SRW) includes magnetic resonance imaging, chest computed tomography (CT) and bone scintigraphy, but 18 Fluorine-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) (18F-FDG-PET/CT (PET-CT)) use is increasing. The aim of this study was to evaluate the impact of PET-CT in the initial staging of patients with metastatic rhabdomyosarcoma enrolled in the European protocol MTS2008. MethodsTwo authors retrospectively reviewed the SRW and PET-CT reports comparing the number and sites of metastases detected. For bone marrow involvement, PET-CT and bone marrow aspirates/biopsies were compared. ResultsAmong 263 metastatic patients enrolled from October 2008 to December 2016, 121 had PET-CT performed at diagnosis, and for 118 of 121 patients, both PET-CT and radiological reports were available for review. PET-CT showed higher sensitivity than SRW in the ability to detect locoregional (96.2% versus 78.5%, P value = 0.0013) and distant lymph node involvement (94.8% versus 79.3%, P value = 0.0242), but sensitivity was lower for intrathoracic sites (lung 79.6% versus 100%, P value = 0.0025). For bone metastasis, PET-CT was more sensitive than bone scintigraphy (96.4% versus 67.9%, P value = 0.0116). The PET-CT sensitivity and specificity to detect marrow involvement were 91.8% and 93.8%, respectively. The mean number of metastatic sites was 1.94 (range 0–5) with PET-CT and 1.72 (range 0–5) with SRW. In four patients (3.4%), PET-CT changed the staging from localised to metastatic disease. ConclusionPET can identify metastatic disease not evident on SRW in a small number of patients. This is because of its higher ability to recognise lymph node and bone involvement. Chest CT remains essential to detect lesions in intrathoracic sites, which can be performed in a one stop-shot routine examination or on a dedicated chest CT scan. PET-CT could replace bone scintigraphy to study bone involvement.

Detecting marrow involvement in lymphoma: Can-18F fluorodeoxyglucose positron emission tomography elude the need for biopsy?

Detecting marrow involvement in lymphoma: Can-18F fluorodeoxyglucose positron emission tomography elude the need for biopsy?

Emerging Data on Management and Imaging of Myeloma Bone Disease

Osteolytic bone disease is the most common complication of multiple myeloma (MM). Whole-body low-dose computed tomography (WBLDCT) is suitable for the detection of osteolytic bone disease in MM patients at diagnosis, replacing conventional radiography skeletal surveys. Whole-body magnetic resonance imaging (WB-MR), or at least MRI of the spine and pelvis (if WB-MRI is not available) should be performed in all asymptomatic patients with no lytic lesions to look for occult disease which may justify treatment. Positron Emission Tomography/Computed Tomography (PET/CT) seems to be inferior to MRI, regarding the detection of marrow involvement in MM, but it is the best technique for optimal definition of complete response and follow-up of myeloma patients to-date. Bisphosphonates (zoledronic acid or pamidronate) remain the cornerstone of the management of myeloma-related bone disease. Denosumab has been recently approved for use in myeloma patients with lytic lesions based on the results of a large phase 3 study, which showed no inferiority of denosumab regarding skeletal-related events compared to zoledronic acid. Denosumab has a better renal safety profile and is administered subcutaneously.

PET/CT Scanner and Bone Marrow Biopsy in Detection of Bone Marrow Involvement in Diffuse Large B-Cell Lymphoma.

Evaluation of bone marrow involvement (BMI) is paramount in diffuse large B-cell lymphoma (DLBCL) for prognostic and therapeutic reasons. PET/CT scanner (PET) is now a routine examination for the staging of DLBCL with prognostic and therapeutic implications. This study evaluates the role of PET for detecting marrow involvement compared to bone marrow biopsy (BMB). This monocentric study included 54 patients diagnosed with DLBCL between 2009 and 2013 and who had FDG PET/CT in a pre-treatment setting. A correlation analysis of the detection of BMI by PET and BMB was performed. A prognostic evaluation of BMI by BMB and/or PET/CT and correlation with an overall 2-year survival were analyzed. PET was more sensitive for the detection of BMI than BMB (92.3% vs. 38.5%). It can be considered a discriminatory Pre-BMB test with a negative predictive value of 97.6%. In addition, BMI by PET had a prognostic value with strong correlation with progression-free survival (PFS) (HR = 3.81; p = 0.013) and overall survival (OS) (HR = 4.12; p = 0.03) while the BMB had not. PET shows superior performance to the BMB for the detection of marrow involvement in DLBCL. It may be considered as the first line examination of bone marrow instead of the biopsy.

Initial Experience With Gallium-68 DOTA-Octreotate PET/CT and Peptide Receptor Radionuclide Therapy for Pediatric Patients With Refractory Metastatic Neuroblastoma.

Pediatric patients with refractory neuroblastoma have limited therapeutic options. Neuroblastoma may express somatostatin receptors (SSTRs) allowing imaging with 68Ga-DOTA-Octreotate (GaTATE) positron emission tomography/computed tomography (PET/CT) and peptide receptor radionuclide therapy (PRRT). We reviewed our experience with this theranostic combination. GaTATE studies (8 patients; 2 to 9 years old) were reviewed and compared with 123I-MIBG or posttreatment 131I-MIBG studies. Immunohistochemistry (IHC) for SSTR subtype 2 was performed in 5 patients. Four patients received PRRT. GaTATE PET showed additional disease in 38% (3/8 patients), and upstaged 1 patient by detecting marrow involvement. IHC detected SSTR 2 in all patients assessed. Six patients were deemed suitable for PRRT on imaging. Four patients received 17 cycles of palliative PRRT (10 111In-DOTATATE; 5 177Lu-DOTATATE; 1 combined 111In and 177Lu-DOTATATE; 1 combined 177Lu and 90Y-DOTATATE) with no significant toxicity attributed to PRRT. All had objective responses. Two survivors are now 40 and 56 months from PRRT commencement. GaTATE PET was positive in a high proportion of patients with refractory neuroblastoma, correlating with SSTR 2 on IHC, with additional disease identified compared with MIBG imaging. PRRT seems safe, feasible, with responses observed in patients with progression despite multimodality treatment. These data support ongoing clinical trials in such patients.

Utility of Bone Marrow Biopsy in the Staging of Diffuse Large B-Cell Lymphoma in the Era of PET-CT

BACKGROUNDDiffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma (NHL). Recent advances in imaging, use of prognostic indices and molecular profiling has improved our ability to characterize disease and predict outcomes in DLBCL. About one-third of patients with DLBCL have bone marrow involvement at the time of diagnosis, and bone marrow aspirate/biopsy (BMAB) is considered gold standard to detect such involvement. 18 F-fluro-2-deoxy-D-glucose positron emission tomography combined with computed tomography (PET-CT), has become standard pre-treatment imaging in DLBCL and may be a non-invasive alternative to BMAB. Prior studies have suggested that PET-CT scan may obviate the need for BMAB as a component for staging patients with newly-diagnosed DLBCL, but owing to a variety of reasons this is not yet a standard of practice. We investigated whether FDG uptake-based bone marrow assessment can replace BMAB in newly-diagnosed DLBCL.METHODSThis study is a single institution retrospective medical records' review. All patients with newly-diagnosed DLBCL at Virginia Mason Medical Center between January 2003 to December 2013 who underwent pre-treatment PET-CT and BMAB were included. FDG-PET/CT images were visually assessed for bone marrow involvement in posterior iliac crest. Patients with primary mediastinal DLBCL, previous history or coexistence of another lymphoma subtype and those with a non-diagnostic BMAB, and in whom the PET-CT did not show marrow signal abnormality were excluded from the analysis. Ann Arbor stage was determined using PET-CT with and without the contribution of BMAB, and the proportion of stage IV cases by each method was measured.RESULTS105 eligible patients were identified. The median age was 62 years (range, 24-88), 62 (59%) were male, 53 (50%) had elevated LDH and 17 (16%) had an ECOG performance status of >2. Thirteen (12%) patients had > 1 extra-nodal site of lymphoma involvement. R-IPI score was 0-1 in 39 (37%), 2 in 42 (40%), 3 in 20 (19%), and 4 in 4 (4%) patients. A total of 38 (36%) patients had bone marrow involvement established by either PET-CT (n=24, 19%), BMAB (n=14, 13%), or both (n=12, 11%). 12 of the 24 patients (50%) with positive PET-CT had marrow involvement by DLBCL, while only 2 of the 81 patients (2%) with negative PET/CT showed marrow involvement. BMAB upstaged 1 of the 53 (2%) stage I/II patients to stage IV. The sensitivity of PET-CT scan to detect marrow involvement by DLBCL was 86% while the specificity was 87%. The positive predictive value of PET-CT was only 50% while the negative predictive value was 98%.CONCLUSIONSIn patients with newly diagnosed DLBCL, PET-CT is complementary to BMAB in detecting marrow involvement by lymphoma. Although PET-CT has a high negative predictive value for bone marrow involvement, it overestimates the number of cases with marrow involvement by lymphoma. In clinical practice, routine BMAB may no longer be necessary for all patients with DLBCL, who are staged by PET-CT, unless the results would change both staging and therapy. The prognostic implication of marrow involvement identified by PET-CT compared to BMAB remains unknown. DisclosuresNo relevant conflicts of interest to declare.

Bone marrow biopsy for hodgkin lymphoma: obligatory or obsolete?

Hodgkin Lymphoma (HL) is diagnosed by tissue biopsy and staged using a variety of techniques including 8F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (FDG-PET/CT) and the more invasive blind bone marrow biopsy (BMB). Advanced disease may be treated with a more intensive chemotherapy protocol, therefore early detection of bone marrow involvement can have therapeutic and prognostic implications. The blind nature of sampling and heterogeneity of marrow involvement limit the sensitivity of BMB. HL is almost universally FDG-PET-avid and there is increasing evidence to suggest this non-invasive test may be able to replace BMB in the staging of HL. Aim To determine whether FDG-PET/CT is as effective as BMB in detecting marrow involvement with HL. Methods A search of hospital pathology and radiology databases was performed to identify all new tissue diagnoses of HL from 2010 to 2014. Patients without BMB reports or FDG-PET/CT imaging reports were excluded, leaving 84 patients available for analysis. Results In 86.9% of patients results were concordant, with 76.2% being FDG-PET/CT and BMB negative and 10.7% being positive in both investigations. Of the discordant results, none were BMB positive and FDG-PET/CT negative. Overall the sensitivity and specificity of FDG-PET/CT was 100% and 85.3% respectively. Conclusion Our study further supports the evidence that BMB is an unnecessary procedure in patients with a negative FDG-PET/CT.

Guidelines for the first line management of classical Hodgkin lymphoma

The guideline group was selected to be representative of UK-based medical experts and patients’ representatives. MEDLINE and EMBASE were searched systematically for publications in English from January 1990 to June 2013 using the key words Hodgkin, Lymphoma, Treatment, Chemotherapy and Radiotherapy. References from relevant publications were also searched. The writing group produced the draft guideline, which was subsequently revised by consensus by members of the Haemato-Oncology Task Force of the British Committee for Standards in Haematology (BCSH). The guideline was then reviewed by a sounding board of approximately 50 UK haematologists and the BCSH and comments incorporated where appropriate. The ‘GRADE’ system was used to quote levels and grades of evidence, details of which can be found in Appendix I. The objective of this guideline is to provide healthcare professionals with clear guidance on the management of patients with classical Hodgkin Lymphoma (HL). The guidance may not be appropriate for all patients with HL and in all cases individual patient circumstances may dictate an alternative approach.

Skeletal Imaging and Management of Bone Disease

Up to 90% of patients with multiple myeloma develop bone lesions. The lesions are purely osteolytic because of increased osteoclast activity and markedly suppressed or absent osteoblast activity. The "gold standard" for imaging myeloma bone lesions is the metastatic bone survey. However, plain radiographs are relatively insensitive and can only demonstrate lytic disease when 30% of trabecular bone loss has occurred. Technicium-99m bone scanning is not appropriate for evaluating myeloma patients since bone scans underestimate the extent of bone involvement in patients with myeloma. The limited reproducibility of bone surveys have led to the use of computerized tomography (CT) scanning, magnetic resonance imaging (MRI) and positron emission tomography (PET) scans to evaluate the extent of bone disease. CT scans are more sensitive than plain radiographs for detecting small lytic lesions, and MRI scans detect marrow involvement by the tumor. PET scans have been used to detect bone lesions in patients with myeloma, are more sensitive than plain radiographs, and have the same sensitivity as MRIs for detecting bone disease in the spine and pelvis. Treatment of myeloma bone disease involves treatment of the underlying malignancy and its manifestations. Current treatments that will be discussed include bisphosphonate therapy, kyphoplasty, vertebroplasty, radiation therapy, and novel agents to suppress osteoclastic bone resorption. In addition, complications with bisphosphonate therapy will be reviewed, in particular, osteonecrosis of the jaw associated with bisphosphonate therapy. As survival of myeloma patients increases, therapies to prevent the complications of aggressive myeloma bone disease become more important.

Evaluation of bone tumors with magnetic resonance imaging and correlation with surgical and gross pathological findings

Objectives: The purpose of this study is to evaluate the role of MRI in cases of bone tumors.To determine the MRI characteristics of different primary bone tumors.Correlate and compare imaging findings with surgical and gross pathological findings whereever possible. Materials and methods: Twenty five patients (either suspected or proven cases of bone tumors) were included in this study.All patients were first evaluated with plain film examination. MRI was performed on a 1.5 Tesla Philips system (Gyroscan). Sequences and planes used were T1W and STIR sequence in coronal plane using body coil followed by T1W and T2W sequences in axial plane supplemented by sagittal and coronal planes using surface coil , second plane of imaging included STIR sequence and post contrast fat sat T1W images . Results : Sensitivity and specificity of MRI in detecting marrow involvement was 100%.MRI detected neurovascular bundle involvement with sensitivity, specificity, positive predictive value and negative predictive value of 100%, 92.8%, 75% and 100% respectively.MRI detected joint involvement with sensitivity, specificity, positive predictive value and negative predictive value of 100%, 86%, 50% and 100% respectively.MRI detected cortical break with sensitivity, specificity, positive predictive value and negative predictive value of 100%, 50%, 80% and 100% respectively. Although MRI could demonstrate different components of tumor, there was no difference in signal intensity patterns of different histological types of tumors. Conclusions : MRI is the preferred modality to image musculoskeletal tumors and should be obtained after radiographic evaluation. Its multiplanar imaging capability helps delineation of tumor and its extent in bone and soft tissues with high contrast resolution.It is an excellent modality to determine neurovascular bundle involvement ,joint involvement,local extent and staging.

Bone marrow biopsy in the initial staging of Hodgkin's disease.

Results of bone marrow biopsy were retrospectively evaluated in 120 previously untreated patients with Hodgkin's disease. The incidence of bone marrow involvement was 13%. All patients with marrow invasion had B symptoms and/or clinically advanced disease. When patients with bone marrow involvement were compared to those without there were significant differences in the incidence of B symptoms, the clinical stage, hemoglobin levels, leukocyte counts, platelet counts, and serum levels of lactate dehydrogenase and alkaline phosphatase. None of 59 patients with clinical stage IA and IIA had evidence of marrow invasion. This study demonstrates that trephine bone marrow biopsy is of value in detecting marrow involvement in specific subgroups of untreated patients with Hodgkin's disease, i.e., those patients with constitutional symptoms and/or clinical stage III or IV. However, bone marrow biopsy adds little to the initial staging of patients with clinical stage IA and IIA. Routine use of this procedure in such patients may be unnecessary.

Is bone marrow examination in small-cell lung cancer really necessary?

Of 403 patients with small-cell lung cancer, we identified by aspiration, biopsy, or both 67 with bone marrow involvement and found the two procedures to be complementary in detecting marrow involvement. The mean surface area of the positive biopsy specimens was significantly greater than that of a randomly selected group of negative biopsy specimens, suggesting that the larger the specimen, the greater the chance of detecting tumour. Patients with marrow involvement had only a slightly worse prognosis compared with other patients who had extensive disease. Only 7 of the 403 patients (1.7%) had extensive disease based on marrow involvement alone. Because bone marrow examination rarely changes the stage of cancer in noninvasively assessed patients, and has no impact on the tolerance of chemotherapy and only a small effect on length of survival, we do not recommend this procedure in the routine staging of small-cell lung cancer.

Evaluation of the Bones and Bone Marrow in Patients With Metastatic Carcinoma of the Prostate: Radiologic, Cytologic and Cytogenetic Findings

We assessed the presence of bone and bone marrow involvement in seven men with advanced carcinoma of the prostate. The routine methods of history-taking, skeletal radiography, and radionuclide bone scans were supplemented by bone marrow aspiration, bone marrow biopsy, and performance of cytogenetic studies upon the aspirated bone marrow, without culture in vitro. Only radiology, bone scan, and marrow biopsy possessed adequate sensitivity. Definite cytogenetic abnormalities (45, XO) were found in two patients but the chromosome studies did not increase the rate of detection of marrow involvement by tumor.

Bone marrow involvement in Burkitt's lymphoma.

Thirteen patients with a malignant lymphoma exhibiting the cytologic characteristics of Burkitt's lymphoma manifested marrow involvement at the time of initial diagnosis (11 patients) or later in the course of the disease (two patients). Eleven patients were 16 years of age or younger. Eight had evidence of abdominal disease, five in the ileocecal area. Despite extensive marrow involvement in most of these patients, frankly leukemic blood pictures were uncommon. Platelet counts and absolute neutrophil counts were frequently normal. Membrane surface markers were studied in four patients. The malignant cells from three exhibited mulambda surface immunoglobulin; the cells from the other manifested muk surface immunoglobulin. All of the patients had a rapid clinical course in spite of intensive chemotherapy. The median survival from detection of marrow involvement was 2.5 months.