Clinical results of coronary artery bypass grafting with use of the internal thoracic artery under low free flow conditions

OBJECTIVE

Even when left internal thoracic artery flow is very low, we have used the artery for grafting without any further maneuvers. In this study, we investigated the clinical results of coronary bypass surgery using the left internal thoracic artery with low free flow.

METHODS

A total of 163 patients were divided into 2 groups: group L (n = 43) had free flow of 20 mL/min or less and group H (n = 120) had free flow of more than 20 mL/min. We performed a comparative study on the basis of coronary angiography and pulsed Doppler echocardiography. Furthermore, 12 months' postoperative graft angiography was carried out in 11 patients from group L.

RESULTS

No patient had low output syndrome or perioperative myocardial infarction. One month after the operation, 3 cases of graft occlusion and 9 cases of the "string sign" were identified in group H. However, group L had no graft occlusion and only 1 case of the "string sign." The 1-month postoperative Doppler echocardiographic study showed no significant differences in the diastolic fraction of velocity time integrals and the diastolic/systolic peak velocity ratio of the grafts. In the 11 patients undergoing angiography after 1 year, graft patency was excellent. Moreover, the graft diameter was significantly larger than it was 1 month after the operation.

CONCLUSION

These results suggest that the left internal thoracic artery can be used for coronary artery bypass grafting even when the flow is less than 20 mL/min.

[Clinical applications and the effect of mexiletine on refractory epilepsies]

Twenty-four patients with refractory epilepsy were treated with mexiletine as an additional antiepileptic drug. As the initial responses, seizures were decreased by 50% or more in 7 (46.7%) of 15 patients with symptomatic partial epilepsy (SPE), in none of 7 with symptomatic generalized epilepsy (SGE), and in 1 of 2 with undetermined epilepsy. Seizures increased in 3 patients (20.0%) with SPE, and in 3 (42.9%) with SGE. Concerning seizure types, mexiletine had significant effects on 1 of 2 patients with simple partial seizures, on 7 of 13 with complex partial seizures, on 1 of 5 with secondarily generalized seizures, and on 1 of 8 with tonic seizures. No patients with a myoclonic seizure or atypical absence improved. Exacerbation of the seizures was observed in 2 of 13 patients with complex partial seizures, in 1 of 5 with secondarily generalized seizures, in 3 of 8 with tonic seizures, and in 2 of 3 with myoclonic seizures. Partial seizures were controlled well, whereas generalized seizures sometimes worsened. EEG improved in 3 patients with SPE; decrease of focal spikes in 2 patients and disappearance of secondary generalization in 1. Follow-up for more than 3 months showed seizures to be lessened in 2 patients. Mexiletine is useful for the treatment of refractory epilepsies, especially SPE.

Human pulmonary dirofilariasis: report of six cases

We report six cases of pulmonary dirofilariasis diagnosed at our laboratory with clinical and pathological features. The nodules of dirofilariasis were round in three cases as previously reported, however dumbbell-shaped in two cases. The nodule did not attach to the pleura in four cases. Microscopically, the nodules were granulomas composed of central coagulation necrosis and peripheral fibrosis with round cell infiltration, histiocytes, and multinucleated giant cells. Necrotic pulmonary artery with single or multiple sections of degenerated nematode was observed in the center of the nodule. Dilated bronchioles with inflammation were observed in the nodule in four cases. Collapse of the alveoli, organizing pneumonia, hemosiderin-laden macrophages were observed around the nodule. We suppose that the nodule is not an infarction but a granuloma caused by antigen released from the nematode. Because the pulmonary dirofilariasis is difficult to be differentiated from primary or metastatic lung carcinoma, and the inflammation exists around the nodule, the nodule should be removed surgically.

Toxoplasma gondii: difference of invasion into tissue of digestive organs between susceptible and resistant strain and influence of IFN-gamma in mice inoculated with the cysts perorally

Because it is widely accepted that there is a significant difference in susceptibility to chronic infection by Toxoplasma gondii among inbred mouse strains with different genetic backgrounds, we compared the distribution of the protozoa in digestive organs at early stages of infection between resistant (BALB/c) and susceptible (C57BL/ 6) mice after peroral infection with Fukaya strain cysts. Furthermore, to determine the influence of interferon gamma (IFN-gamma) on the infectivity of the cysts to the digestive tract, homozygous IFN-gamma knockout mice were utilized. Quantitative competitive polymerase chain reaction (QC-PCR) was employed to assess the distribution of T. gondii in different organs at various times after ingestion of cysts. SAG1, a T. gondii-specific gene, was detected in the small intestine and the caecum in wild-type C57BL/6 mice and in the whole digestive tract in IFN-gamma knockout C57BL/6 at 24 hr after infection. No detectable reaction in QC-PCR was observed in BALB/c mice at 24 hr after ingestion of the cysts. Destruction of the IFN-gamma gene showed less effect on the resistance to infection in BALB/c mice, but remarkable augmentation of infectivity of T. gondii to the rectum and peripheral blood was observed in C57BL/6 mice.

A plasma cell leukemia patient showing bialleic 14q translocations: t(2;14) and t(11;14)

We report here an IgG/lambda-type plasma cell leukemia patient showing bialleic 14q32 translocations. All immunoglobulins were suppressed in this patient, but a small amount of monoclonal IgG was detected by immunoelectrophoresis. Two cells of six peripheral blood mononuclear cells showed 46,XY,t(2;14)(q11;q32), i(8)(q10), t(11;14)(q13;q32), del(12)(q13.1) by karyotypic analysis. We confirmed the juxtaposition of IgH and PRAD1/Cyclin D1 genes by fluorescent in situ hybridization and overexpression of the PRAD1/Cyclin D1 gene, but Southern analysis showed no bcl-1 rearrangement. We analyzed the t(2;14)(q11;q32) using DNA fragments derived from childhood B-chronic lymphocytic leukemia cases bearing t(2;14)(p13;q32). Southern and Northern analyses demonstrated no alteration of these genes, indicating that this t(2;14) was different from that of childhood B-chronic lymphocytic leukemia. At the IgH loci, Southern analysis showed two rearranged bands and one germ-line band of JH. Cmicro was deleted on one rearranged allele but remained on the other, suggesting that the chromosome translocation occurred after productive class switch recombination on the Cmicro deleted allele.

Should use of the internal thoracic artery be avoided under conditions of low free flow? Postoperative hemodynamic assessment using pulsed Doppler echocardiography

There are cases in which it is thought advisable to avoid the use of the left internal thoracic artery (LITA) in coronary artery bypass grafting (CABG) due to its low free flow (FF). However, even though the LITA flow is very low, anastomosis without any further maneuvers intraluminally is recommended. The present study investigated the clinical results of CABG, using a LITA with low FF. The 60 cases of CABG were divided into 2 groups: (i) Group L (n = 23), in which LITA FF was less than 20 ml/min; and (ii) Group H (n = 37) in which it was more than 20 ml/min. A comparative study on the basis of coronary angiography and pulsed Doppler echocardiography was performed. In both groups, no LITA graft occlusion was identified, and the 'string sign' was also absent. In the LITA blood waveform, all cases exhibited a biphasic pattern with a higher mid-diastolic and a lower end-systolic component. There were no significant differences in the LITA flow diastolic peak velocity, velocity time integrals and the diastolic/systolic peak velocity ratios. These results suggest that the LITA can be used for CABG even when the free flow is less than 20 ml/min.

Cytokine and endothelial damage in pulsatile and nonpulsatile cardiopulmonary bypass

Recently, several types of centrifugal pumps have been widely used as the main pumps for cardiopulmonary bypass (CPB). However, according to the results of our experimental studies, after cardiogenic shock, pulsatile flow was effective in maintaining the functions and microcirculations of end organs, especially those of the liver and kidney. To estimate the effectiveness of pulsatility during CPB, cytokine and endothelin and other metabolic parameters were measured in clinical pulsatile and nonpulsatile CPB cases. From March to May 1997, CPB was performed in 18 elective cases (14 ischemic and 4 valvular disease). In 9 cases, pulsatile perfusion was achieved by the Jostra HL20, which is a newly developed CPB pump (Group P). A nonpulsatile centrifugal pump was used in 9 patients (Group NP). In both groups, as chemical and metabolic mediators, interleukin-8 (IL-8), endothelin-1 (ET-1), and plasma free hemoglobin were measured before and during CPB, and 0.5, 3, 6, 9, 18 h after weaning from CPB. This pulsatile CPB pump could be very simply and easily controlled and could easily produce pulsatile flow. There were no significant differences in CPB time (CPBT), aortic cross clamp time (ACCT), mean aortic pressure, or pump flow during CPB between the both groups. The ET-1 level of Group P was significantly (p < 0.05) lower than that of Group NP 9 h after CPB weaning. The IL-8 level of Group P also showed a lower value than that of Group NP. As for plasma free hemoglobin, there were no significant differences between the groups. These results suggested that even in conventional CPB, pulsatility was effective to reduce endothelial damage and suppress cytokine activation. It may play a important role in maintaining the functions and microcirculations of end organs during CPB.

Surgical treatment of 22 cardiac myxomas: A review

Twenty-two cases of cardiac myxomas were reviewed. The patients were 8 men and 14 women ranging in age from 12 to 73 (mean: 50.8 +/- 16. 6) at operation. They suffered from dyspnea, palpitation, and cough, similar to mitral disease symptoms, and cerebral emboli in 6 patients (30%) with left atrial myxomas. Echocardiography, especially transesophageal, was useful in diagnosing cardiac tumors and location. In 20 cases, tumors were at the left atrium and at the right in 2. Left atrial myxomas were approached through a septal incision in 17 cases; a large circular incision of the biatrium was used in 3 patients with large tumors or mitral regurgitation. Left atrial myxomas were attached to the atrial septum in 17 cases, the posterior wall of the left atrium in 2, and near the posterior commissure of the mitral valve in 1. Right atrial myxomas were attached to the atrial septum in 1 and posterior wall beside the inferior vena cava in 1. Resected myxomas weighed from 10 to 90 (mean: 39.1 +/- 19.1) g. No correlation was seen between features such as neurologic symptoms, feeding artery on coronary angiography, or functional status and tumor weight. No recurrence was seen.

Detection of inducible nitric oxide synthase (iNOS) mRNA by RT-PCR in ATL patients and HTLV-I infected cell lines: clinical features and apoptosis by NOS inhibitor

Various tumors have been reported to express an inducible form of nitric oxide synthase (iNOS), and nitric oxide (NO) may affect the clinicopathological features of these tumors. Previously, Burkitt's lymphoma and Epstein-Barr virus (EBV)-infected cells were shown to express iNOS constitutively at a low level. We analyzed iNOS expression by the reverse transcriptase-polymerase reaction method (RT-PCR) in eight HTLV-I-infected cell lines (five were ATL-derived lines and there were in vitro transformed lines), nine ATL patients (three were chronic, two were acute, and four were lymphoma type), and an HTLV-I-negative T cell line (CEM). In four ATL derived and in all three in vitro transformed cell lines, iNOS was expressed constitutively, but it was not expressed in CEM cells. Four out of nine ATL patients also showed iNOS expression. The expression of iNOS was found in all subtypes of ATL. Three of four iNOS-positive patients had infiltration of ATL cells to organs such as skin, lung, or liver. In NOS inhibitor (NG-monomethyl-L-arginine: L-NMMA)-containing medium, an iNOS-positive ATL cell line (K3T) showed growth inhibition and DNA ladder. Although only a limited number of patients was analyzed, our results suggest that NO may be involved in the invasive character of ATL cells. The NOS inhibitor can induce apoptosis in an ATL cell line, as it does in EBV-infected cell lines.

[Effectiveness of low dose continuous infusion of alpha-hANP from the start of cardiopulmonary bypass]

In this study, we used alpha-human atrial natriuretic peptide (hANP) from staring on cardiopulmonary bypass and evaluated for the hemodynamics, ANP, renin activity, aldosterone, urine volume, glomerular filtration rate (GFR) and so on. The hANP decreased renin activity, aldosterone, systemic vascular resistance and increased urine volume, GFR and use of furosemide and KCL were decreased. We concluded that hANP was effective for hemodynamics, renal function and hormonal release on intra and post-operation in cardiac surgery, and low dose continuous infusion of alpha-hANP from staring on cardiopulmonary bypass will be expected as a newly application.

Comparative studies of the toxicity of standard reference materials in various cytotoxicity tests and in vivo implantation tests

Polyurethane films that contained various amounts of zinc diethyldithiocarbamate (ZDEC) and zinc dibutyldithiocarbamate (ZDBC) were prepared as standard reference materials (SRM). Using three cell lines of V79, L929, and Balb/3T3 cells, the cytotoxicity of the dithiocarbamates and the SRM films were compared by agar diffusion assay, filter diffusion assay, neutral red assay, cell growth assay, and colony assay. Among these in vitro cytotoxicity tests, colony assay was found to be the most sensitive method for detecting the cytotoxicity. The cytotoxic potentials of extracts from SRM films correlated well with the concentrations of ZDEC or ZDBC involved in SRM. When various rubber materials including SRM and surgical rubber latex materials were tested, cytotoxic potentials of these extracts were also correlated with the inflammatory tissue capsule thickness in short-term implantation tests. On the basis of these results, the SRM is judged to be useful for validating test sensitivity, and comparing the correlation between in vitro and in vivo responses.

Protective immunity induced by vaccination with SAG1 gene-transfected cells against Toxoplasma gondii-infection in mice

To develop a vaccine by augmenting the protective cellular immunity against Toxoplasma gondii (T. gondii)-infection, T gondii SAG1 gene-transfectants were established by using RMA.S (H-2b), a murine transporter associated with the antigen processing (TAP) molecule-deficient lymphoma line, as a host antigen-presenting cell (APC). Immunization of C57BL/6 mice with the SAG1-transfected RMA.S induced CD8+ cytotoxic T lymphocytes (CTL) specific for not only SAG1-transfected RMA.S but also T gondii-infected RMA.S, and elicited protective responses to infection with a virulent T. gondii strain, RH.

Expression of PRAD1/cyclin D1 in plasma cell malignancy: incidence and prognostic aspects

We analysed PRAD1/cyclin D1 expression in 20 patients with plasma cell malignancy by Northern analysis. 6/17 multiple myeloma patients and 3/3 plasma cell leukaemia patients showed PRAD1/cyclin D1 expression. This incidence appeared to be higher than the expected incidence based on previous studies. Southern analysis did not show rearrangement of the bcl-1 region. Although there was no statistical difference, the PRAD1/cyclin D1 negative group showed a 1-year survival of 81.8%, 3-year survival of 45.5% and 5-year survival of 22.7%, and those for the PRAD1/cyclin D1 positive group were 63.5%, 16.9% and 16.9%, respectively. Further study is required to determine whether PRAD1/cyclin D1 expression is a prognostic factor.

Spontaneous recanalization of postoperative severe graft stenosis. What is the cause and prognosis of the "string sign" in the internal thoracic artery?

A 68-year-old female with unstable angina was treated surgically. She was referred to the surgical ward by cardiologists because of a diagnosis of unstable angina with three vessel disease. On a coronary angiogram (CAG), 90% stenoses were found in the left anterior descending coronary artery (LAD), circumflex (CX), and right coronary artery (RCA). She received elective coronary artery bypass grafting (CABG), in which the left internal thoracic artery (LITA) was anastomosed to the LAD and reversed saphenous vein grafts (SVG) were made to segment 12 of the CX, and segment 4PD of the RCA, respectively. The postoperative course was uneventful, but postoperative early graftgraphy revealed distal narrowing of the LITA graft as the so-called "string sign". However, one year post surgery, the LITA string sign was not found and its patency had markedly improved on the second graftgram. It is reported that the LITA "string sign" might cause late graft occlusion. However, this LITA graft evidently enlarged the size and increased the flow of the artery in proportion to myocardial blood demand. To our knowledge, it has not been reported that an in situ LITA string sign on postoperative early graftgram has disappeared in the late phase. We hypothesize that the LITA string sign might be caused by several different factors such as flow competition, spasm, and/or technical problems. In any event, the LITA string sign does not cause graft occlusion in the late postoperative period in every case.

Effects of phosphodiesterase inhibitors after coronary artery bypass grafting

The aim of this study was to estimate the postoperative effects of phosphodiesterase (PDE) inhibitors (milrinone and olprinone) after coronary artery bypass grafting (CABG). To prevent hypotension caused by the PDE inhibitors, low dose of catecholamines were used concomitantly. A total of 34 elective CABG cases were tested. In 12 cases, 0.25 microg kg(-1) min(-1) of milrinone, 3 microg kg(-1) min(-1) of dobutamine (DOB) and dopamine (DOA) were used concomitantly (Group-M). In another 10 patients, 0.1 microg kg(-1) min(-1) of olprinone and the same doses of the catecholamines were infused (Group-O). As a control, the same doses of DOA and DOB only were administered in 12 patients (Group-C). When the pump flow of the cardiopulmonary bypass (CPB) decreased to half, these drugs were given in all groups. Hemodynamics were recorded before CPB, just after the operation, and 3, 6, 12, 24, 48 and 72 h after the operation. Both milrinone and olprinone increased the cardiac index and decreased systemic vascular resistance to almost the same degree. Olprinone decreased mean aortic and pulmonary artery pressures, and also significantly reduced the preload of both right and left heart compared with milrinone. Significant hypotension was not detected due to the concomitant usage of low-dose catecholamines. This concomitant usage of PDE inhibitors and catecholamines allowed easy weaning from CPB, demonstrating excellent hemodynamics after CABG. Good oxygen demand and supply balance were maintained in peripheral tissue. These results suggest that these new PDE inhibitors may be effective not only for weaning from CPB but also for post-cardiotomy cardiogenic shock.

Congenital coronary artery fistula treated surgically in the right atrium and the atrial septum

Various surgical techniques have been employed according to the type of the coronary fistula. In this case, preoperative examinations by aortography and MRI revealed a coronary artery fistula which originated from a site just proximal of the RCA, ran through the interatrial septum and drained into the posterior wall of right atrium. The ratio of pulmonary to systemic blood flow (Qp/Qs) was 1. 95. During surgery, we were not able to ligate or divide the fistula on the cardiac surface because the fistulous vessel originated from the posterior aspect of the proximal RCA. After establishing a cardiopulmonary bypass, the opening of the fistula in the right atrium was closed with an autologous pericardium patch, the surface of the interatrial septum was incised and the fistula was identified. The conduit was then divided and closed in the atrial septum. The postoperative course was uneventful. This approach is able to interrupt the fistula safely without interfering with normal coronary flow. Closure of the outlet and division of the fistula itself is a recommendable method to insure interruption of fistulous communication.

Role of estrogen and estrogen-related growth factor in the mechanism of hormone dependency of endometrial carcinoma cells

The role of estrogen and estrogen-related growth factors in the mechanism of hormone dependency of endometrial adenocarcinoma cells was investigated. The proliferation of hormone-responsive human endometrial adenocarcinoma cells (Ishikawa cells), which possess both estrogen and progesterone receptors, was optimally stimulated by 10 nM estradiol. Both transforming growth factor (TGF)-alpha and epidermal growth factor (EGF), added to the culture media, stimulated the proliferation of Ishikawa cells in a dose-dependent manner. Anti-TGF-alpha antibody completely eliminated the stimulatory effects of TGF-alpha. Anti-EGF receptor antibody inhibited the proliferation of these cells. The production of TGF-alpha into culture media was 5-40 pg/10 cells/24 h in 9 human endometrial adenocarcinoma cells. Ten nanomoles of estradiol increased the TGF-alpha production of Ishikawa cells by approximately 2.5-fold of the control level. In contrast, the production of TGF-alpha in hormone-unresponsive HEC-50 cels was not influenced by estradiol. C-erbB-2 oncoprotein expression of human endometrial adenocarcinoma cells, detected by both immunocytochemical staining and Western blot analysis, was associated with the tumor grade of the original tumor tissues. Ten nanomoles of estradiol clearly increased the c-erbB-2 oncoprotein levels at an optimal incubation period of 72 h, whereas estradiol did not affect the expression in HEC-50 cells.

Post-operative effects of olprinone after coronary artery bypass grafting

The aim of this study was to test the effects of olprinone after coronary artery bypass grafting (CABG). In order to prevent hypotension caused by olprinone, low doses of catecolamines were used concomitantly. Total 22 elective CABG cases were evaluated. In all cases, moderate hypothermia and cardioplegic cardiac arrest were performed. In 10 cases, continuous intravenous 0.1 microg/kg/min of olprinone, 3 microg/kg/min of dobutamine (DOB) and dopamine (DOA) as the initial doses, were used concomitantly (Group I). As a control, the same initial doses of catecolamine (DOB and DOA) of Group I were administered in another 12 patients (Group II). When the pump flow of cardiopulmonary bypass (CPB) was decreased to half, these drugs were administered in both groups. Hemodynamics were recorded before CPB, just after the operation and 3, 6, 12, 24, 48, and 72 hours after the operation. Three hours after the operation, both mean aortic pressure (AoP) and pulmonary artery pressures (PAP) of Group I demonstrated significantly lower values than those of Group II. Cardiac index (CI) of Group I showed significantly higher values than that of Group II until 6 hours after surgery. The systemic vascular resistance index (SVRI) of Group I indicated a significantly lower value than that of Group II until 24 hours after the operation. Pulmonary capillary wedge pressure (PCWP) of Group I demonstrated a significantly lower value than that of Group II. There were no significant differences in urine output, oxygen delivery (DO2) and oxygen consumption (VO2) between both groups. Olprinone increased CI and decreased SVRI, and it showed easy weaning from CPB, demonstrating excellent hemodynamics after CABG. These results suggested that this new phosphodiesterase inhibitor may be effective for not only weaning from CPB but also post-cardiotomy cardiogenic shock.

[A case of coronary arterial fistula originating from both coronary artery and draining to the right atrium]

We encountered a case with bilateral fistulas of coronary arteries into the right atrium, a rare cardiac anomaly. The case was a 17-year-old woman, who visited our hospital at the age of 11 because of fever. At that time, the patient was diagnosed as having a left coronary artery-right atrial fistula through cardiac catheterization (CAG). When the patient developed staphylococcus infected endocarditis at the age of 16, a thick fistula of the coronary artery, directly running from the deformed left coronary arterial sinus, a fistula of the left circumflex branch, and also a fistula of the right coronary artery into the right atrium were detected by CAG. The outlets of these fistulas were closed from the inside of the right atrium under artificial cardiopulmonary circulation and cardiac arrest, and each fistula was ligated at the outside of cardiac chambers. At that time, we took particular care that any branch of the sinuatrial node was not injured. Although all fistulas were confirmed to be closed by postoperative CAG, and no evidence of ischemia was detected by myocardial scintigraphy, deformity of the left coronary arterial sinus remained, requiring further follow up.

Establishment of a monoclonal antibody to human myeloma cell: relation to chemotherapy and extramedullar infiltration

Resistance of myeloma cells to melphalan (L-PAM) is a serious problem. To investigate mechanisms of drug resistance, we generated a monoclonal antibody, clone O3, to melphalan-resistant myeloma cells, KHM-11R. Western blot analysis showed that molecular weight of O3 antigen was approximately 90 kDa. Expression of O3 antigen was approximately two times higher in KHM-11R than in parental melphalan sensitive cell line, KHM-11. O3 was preferentially expressed in plasma cell, B-cell, and monocytic cell lines, but not in T-cell lines. Analysis of bone marrow samples from myeloma patients revealed that 13 of 23 samples expressed O3 antigen at various levels, and that O3 antigen expression in patients correlate with preceding chemotherapy, advanced clinical stage and extramedullar invasion of myeloma cells. Furthermore, patients expressing O3 antigen at the time of diagnosis tended to have poor prognosis. The investigation of O3 antigen in myeloma cells will be useful to reveal the pathophysiology of extramedullar invasion and the mechanism of cell killing by melphalan.

Expression of Bcl-2 family of proteins in fresh myeloma cells

Members of the Bcl-2 family of proteins, Bcl-2, Bcl-X(L), Bcl-Xs and Bax, are considered to play important roles in the regulation of apoptosis and drug resistance. To understand the significance of these proteins in fresh human myeloma cells, expression of Bcl-2 family of proteins was analyzed by Western blotting in 17 cases with multiple myeloma (MM) and three cases with plasma cell leukemia (PCL). Bcl-2 and Bcl-X(L) were found in 12 and nine samples, respectively. All PCL cases showed co-expression of Bcl-2 and Bcl-X(L). Analysis of MM cases showed that Bcl-2 was preferentially expressed in samples from cases with early clinical stage while Bcl-X(L) tended to be expressed in samples from cases at advanced clinical stage. Bcl-X(L) was significantly expressed in tumor cells from cases with extramedullar lesions. There was no correlation between the expression levels of Bcl-2 or Bcl-X(L) and preceding chemotherapy. Expression of Bax was found in only one patient who had pleural effusion caused by invasion of myeloma cells and a high serum LDH level. Survival analysis revealed that there was no statistical significance in expression of Bcl-2 or Bcl-X(L) although Bcl-X(L) tended to be expressed in cases with poor prognosis. These findings indicate that expression of Bcl-2 family of proteins is heterogeneously regulated in fresh myeloma cells. Expression of Bcl-X(L) and Bcl-2 may correlate with extramedullar invasion and early stage of the disease, respectively. Absence of Bax in myeloma cells may contribute to low sensitivity of myeloma cells to anti-cancer agents since Bax is reported to mediate cytotoxicity of some anti-cancer drugs.