Diagnosis, treatment, and response assessment in solitary plasmacytoma: updated recommendations from a European Expert Panel

Solitary plasmacytoma is an infrequent form of plasma cell dyscrasia that presents as a single mass of monoclonal plasma cells, located either extramedullary or intraosseous. In some patients, a bone marrow aspiration can detect a low monoclonal plasma cell infiltration which indicates a high risk of early progression to an overt myeloma disease. Before treatment initiation, whole body positron emission tomography-computed tomography or magnetic resonance imaging should be performed to exclude the presence of additional malignant lesions. For decades, treatment has been based on high-dose radiation, but studies exploring the potential benefit of systemic therapies for high-risk patients are urgently needed. In this review, a panel of expert European hematologists updates the recommendations on the diagnosis and management of patients with solitary plasmacytoma.

Prevention and management of adverse events of Novel agents in multiple myeloma: A consensus of the european myeloma network

During the last few years, several new drugs have been introduced for treatment of patients with multiple myeloma, which have significantly improved treatment outcome. All of these novel substances differ at least in part in their mode of action from similar drugs of the same drug class, or are representatives of new drugs classes, and as such present with very specific side effect profiles. In this review, we summarize these adverse events, provide information on their prevention, and give practical guidance for monitoring of patients and for management of adverse events.Leukemia accepted article preview online, 18 December 2017. doi:10.1038/leu.2017.353.

Insight into human protease activated receptor-1 as anticancer target by molecular modelling

Protease-activated receptor 1 (PAR1) has been established as a promising target in many diseases, including various cancers. Strong evidence also suggests its role in metastasis. It is proved experimentally that PAR1 can induce numerous cell phenotypes, i.e. proliferation and differentiation. A strong link between PAR1 gene overexpression and high levels of ß-catenin was suggested by a study of the PAR1-Gα(13)-DVL axis in ß-catenin stabilization in cancers. An in vitro study was carried out to analyze PAR1 expression by flow cytometry on CD38+138+ plasma cells obtained from patients either at diagnosis (n: 46) (newly diagnosed multiple myeloma (NDMM)) or at relapse (n: 45) (relapsed/refractory multiple myeloma (RRMM)) and compared with the controls. Our previously synthesized benzoxazole (XT2B) and benzamide (XT5) derivatives were tested with in vitro 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, which revealed significant inhibitory activity on PAR1. We provide docking studies using Autodock Vina of these newly tested compounds to compare with the known PAR1 inhibitors in order to examine the binding mechanisms. In addition, the docking results are validated using HYDE binding assessment and a neural network (NN) scoring function.

Management of treatment-emergent peripheral neuropathy in multiple myeloma

Peripheral neuropathy (PN) is one of the most important complications of multiple myeloma (MM) treatment. PN can be caused by MM itself, either by the effects of the monoclonal protein or in the form of radiculopathy from direct compression, and particularly by certain therapies, including bortezomib, thalidomide, vinca alkaloids and cisplatin. Clinical evaluation has shown that up to 20% of MM patients have PN at diagnosis and as many as 75% may experience treatment-emergent PN during therapy. The incidence, symptoms, reversibility, predisposing factors and etiology of treatment-emergent PN vary among MM therapies, with PN incidence also affected by the dose, schedule and combinations of potentially neurotoxic agents. Effective management of treatment-emergent PN is critical to minimize the incidence and severity of this complication, while maintaining therapeutic efficacy. Herein, the state of knowledge regarding treatment-emergent PN in MM patients and current management practices are outlined, and recommendations regarding optimal strategies for PN management during MM treatment are provided. These strategies include early and regular monitoring with neurological evaluation, with dose modification and treatment discontinuation as indicated. Areas requiring further research include the development of MM-specific, patient-focused assessment tools, pharmacogenomic analysis of patient DNA, and trials to assess the efficacy of pharmacological interventions.

Is it time to revisit our current hematopoietic progenitor cell quantification methods in the clinic?

In the clinical practice of hematopoietic SCT, the minimum numbers of cells required for a successful engraftment are defined on the basis of their CD45 and CD34 expression profiles. However, the quantity of earlier progenitors or CD34-positive cells at different differentiation stages within stem cell grafts is not generally taken into consideration. During the last decade, various teams have quantified the number of cells expressing various combinations of CD34, CD38, CD133, CD90 co-expression and/or aldehyde dehydrogenase functional capacity using flow cytometry. Some of these studies resulted in the greater appreciation that combinations of these Ags were associated with varied myeloid, erythroid and platelet engraftment rates whereas others showed that the relative absence or presence of these markers could define cells responsible for either short- or long-term engraftment. These findings were also extended to differences between progenitor cell populations found within BM vs peripheral or cord-blood grafts. Cells harvested from donors are also generally frozen and stored; thawed cells have variable levels of viability and functional capacity based on the time tested post thaw, which also can be assessed by flow cytometry. Finally, flow cytometry has the potential for analysis of cells carrying a mesenchymal stem cell phenotype, which may be quiescent within some of the stem cell products. This review will address the need for stem cell subpopulation quantification and summarize existing published data to identify some Ags and functional characteristics that can be applicable to daily clinical practice.

5-azacytidine treatment results in myelodysplastic syndrome

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Background: Myelodysplastic syndrome (MDS) is a clonal disease of hematopoiesis characterized by dysplasia in one or more series. 5-azacytidine (5-AZA) which is one of the methyl transferase inhibitors, targets the epigenetic changes in MDS and has been used for the last few years. Phase III studies which compare 5-AZA with supportive therapies report response rates up to 60%. Methods: In this study the aim was to retrospectively analyze the response rates of 26 MDS patients who were treated with 5-AZA between years 2002–2008. The patients were; median age 58 (21–84); male/female = 16/10; RAEB-I (7 patients); RAEB-II (18 patients); ve CMML (1 patient); secondary MDS (2 patients). According to an international prognostic scoring system, 6 patients were intermediate-1; 9 patients were intermediate-2; and 11 patients were high risk. Nine patients received 5-AZA as first-line therapy. The median leukocyte counts, absolute neutrophil counts (ANC), hemoglobin values, and thrombocyte counts at the begining of the cycles were; 2.4 (0.5–23)x10e9/L, 0.7 (0.1–16.5)x10e9/L, 8.6(5.3–11.4) gr/dl, 41(4–35)x10e9/L, respectively. The karyotype analysis revealed del5q in 3 patients; -7/del7q in 6 patients; trisomy 8 in 7 patients, del20q, del11q and complex karyotype (del7q+del5q+delY) in 1 patient each. The median cycles completed were 2 (1–6). Results: Seven patient were not elligible for response evaluation. Nine patients (47%) did not respond to the therapy and 8 of them were lost. Ten patients (53%) responded to the therapy with complete remission (n=4), partial remission (n = 2) and hematological improvement (n = 4). The responders and non-responders were similar in terms of median age, sex and pretreatment leukocyte, ANC and hemoglobin levels. However, there was statistically significant difference in terms of initial thrombocyte counts, total number of cycles received and serum ferritin levels. The patients who received 5-AZA as first line therapy had beter response than others (71% versus 29%). Conclusions: The observed response to 5-AZA therapy was similar to the reported rates in the literature. The most important factors for response were initial thrombocyte counts, total number of cycles, other therapies received before 5-AZA and the serum ferritin levels.

No significant financial relationships to disclose.

International myeloma working group consensus statement and guidelines regarding the current role of imaging techniques in the diagnosis and monitoring of multiple Myeloma

Several imaging technologies are used for the diagnosis and management of patients with multiple myeloma (MM). Conventional radiography, computed tomography (CT), magnetic resonance imaging (MRI) and nuclear medicine imaging are all used in an attempt to better clarify the extent of bone disease and soft tissue disease in MM. This review summarizes all available data in the literature and provides recommendations for the use of each of the technologies. Conventional radiography still remains the 'gold standard' of the staging procedure of newly diagnosed and relapsed myeloma patients. MRI gives information complementary to skeletal survey and is recommended in MM patients with normal conventional radiography and in all patients with an apparently solitary plasmacytoma of bone. Urgent MRI or CT (if MRI is not available) is the diagnostic procedure of choice to assess suspected cord compression. Bone scintigraphy has no place in the routine staging of myeloma, whereas sequential dual-energy X-ray absorptiometry scans are not recommended. Positron emission tomography/CT or MIBI imaging are also not recommended for routine use in the management of myeloma patients, although both techniques may be useful in selected cases that warrant clarification of previous imaging findings, but such an approach should ideally be made within the context of a clinical trial.

International uniform response criteria for multiple myeloma

New uniform response criteria are required to adequately assess clinical outcomes in myeloma. The European Group for Blood and Bone Marrow Transplant/International Bone Marrow Transplant Registry criteria have been expanded, clarified and updated to provide a new comprehensive evaluation system. Categories for stringent complete response and very good partial response are added. The serum free light-chain assay is included to allow evaluation of patients with oligo-secretory disease. Inconsistencies in prior criteria are clarified making confirmation of response and disease progression easier to perform. Emphasis is placed upon time to event and duration of response as critical end points. The requirements necessary to use overall survival duration as the ultimate end point are discussed. It is anticipated that the International Response Criteria for multiple myeloma will be widely used in future clinical trials of myeloma.

Evaluation of the effect of transplant-related factors and tissue injury on donor-derived hepatocyte and gastrointestinal epithelial cell repopulation following hematopoietic cell transplantation

The aim of this study was to detect donor-derived hepatocytes and gastrointestinal epithelial cells in recipients of sex-mismatched allogeneic hematopoietic cell transplants, and to assess the effect of tissue injury on the extent of the repopulation. A total of 29 paraffin-embedded biopsy samples were reviewed. Double labeling by immunohistochemistry and fluorescence in situ hybridization was performed. Eighty-nine percent of sex-mismatched samples with histologic evidence of injury demonstrated the presence of donor-derived hepatocytes and gastrointestinal epithelial cells (mean 2.4%). None of the hepatocytes and gastrointestinal epithelial cells in samples obtained from female recipients with female donors showed a Y chromosome signal. The proportion of donor-derived hepatocyte and gastrointestinal epithelial cells in samples with severe graft-versus-host disease was greater than that of samples with mild/moderate graft-versus-host disease (P = 0.09). No relationship between the source of stem cells and the population rate was detected (P > 0.05). We conclude that some recipient hepatocytes and gastrointestinal tract epithelial cells are replaced by donor-derived cells during tissue injury. The severity of tissue injury seems to influence on the extent of this repopulation.

Low-dose cytosine arabinoside (LD-AraC) vs LD-AraC plus granulocyte/macrophage colony stimulating factor vs LD-AraC plus Interleukin-3 for myelodysplastic syndrome patients with a high risk of developing acute leukemia: final results of a randomized phase III study (06903) of the EORTC Leukemia Cooperative Group

In this randomized phase III study of the EORTC Leukemia Cooperative Group, patients with myelodysplastic syndromes (MDS) with 10-30% bone marrow blasts and hematopoietic failure were treated with low-dose cytosine arabinoside (LD-AraC) (2 x 10 mg/m2/day subcutaneously (s.c.) days 1-14) either alone or in combination with rhGM-CSF or interleukin-3 (IL-3) both given s.c. at a dose of 150 microg/day from day 8 to 21. A total of 180 evaluable patients with a median age of 65 years and refractory anemia with an excess of blasts (RAEB, n = 107) or RAEB in transformation (RAEBt, n = 73) were randomized. There were no differences among the three treatment regimens with respect to numbers of courses applied or treatment delays. Hemorrhage occurred in approximately 40% in all arms, whereas infection rates were higher in the granulocyte/macrophage colony stimulating factor (GM-CSF)- or IL3-containing arm. The overall response rate was 38.6% with no statistically significant difference among the three arms. In summary, a substantial proportion of patients had achieved relatively durable responses in all the three arms. No influence of either growth factor was detected on the grade of cytopenia. Thus, the combination of LD-AraC with GM-CSF or IL-3 cannot be recommended for routine use in a high-risk MDS population.

Role of pretransplant interferon-alpha(IFN) treatment in the outcome of stem cell transplantation (SCT) from related donors in chronic myelogenous leukemia (CML): results from three Turkish transplant centers

Since transplantation cannot be performed immediately after the diagnosis of chronic myelogenous leukemia (CML), interferon treatment is usually required. This study aims to analyze the effects of interferon-alpha (IFN) treatment on allogeneic stem cell transplantation (SCT) outcome. A total of 106 patients aged 16-47 years and transplanted from HLA-identical sibling donors for CML in chronic phase (CP) were evaluated. In all, 48 had received IFN-alpha for a median duration of 5 months (1-18 months) until a median of 1 month prior to transplantation. Of the patients, 50 have received bone marrow transplant (BMT) whereas 56 have received peripheral blood stem cells (PBSCT) between 1991 and 1999 in three major transplant centers in Turkey. Patient characteristics in both groups were similar. More hematological responders were present in the IFN(+) patients (P=0.0001). No difference was found in engraftment kinetics. The incidences of acute or chronic graft-versus-host disease (GVHD), relapse and graft failure were similar in all patients regardless of stem cell source. Overall survival (OS) and disease-free survival (DFS) at 2 years were similar for both IFN(+) or (-) patients following SCT. With multivariate analysis, pretransplant IFN-alpha use, stem cell source, transplant year and CD34+ cell content were not found to be risk factors for OS. In conclusion, prior IFN exposure did not impair BMT or PBSCT outcome.

In vivo use of all-trans retinoic acid prior to induction chemotherapy improves complete remission rate and increases rhodamine 123 uptake in patients with de novo acute myeloid leukemia

All-trans retinoic acid (ATRA) is used in the treatment of acute promyelocytic leukemia. Because ATRA has effects (increase in apoptosis, suppression of bcl-2), it has also been used for the treatment of other French-American-British (FAB) subtypes of acute myelogenous leukemia (AML). To find out the in vivo and in vitro effects of ATRA in AML, we analyzed 37 patients with de novo AML. Twenty-seven patients received ATRA before remission-induction (RI) treatment (ATRA group). Results were compared to a control group (10 patients) that received induction without ATRA during the same time period. Bone marrow or peripheral blood samples were collected from all patients on d 0 and 4. The immunphenotype, myeloperoxidase (MPO), reac tion and the efflux uptake of rhodamine 123 (Rh123) were analyzed on myeloblasts in these samples. In the myeloblasts from patients treated with ATRA, the uptake of Rh123 was increased significantly (p = 0.026) from d 0 to d 4, and all other parameters remained unaltered. ATRA administration increased the complete remission (CR) rate (88%, 22/25 vs 55%, 5/9) significantly (p = 0.042). Logistic regression analysis revealed that ATRA administration was the important factor in CR, among other potential factors including age, white blood count, bcl-2 expression, and the uptake and efflux of Rh123 (p = 0.05). Estimated disease-free survival and overall survival were similar between these two groups (43% vs 37.5% and 51.2% vs 37.5%, respectively). In conclusion, ATRA treatment prior to RI treatment may improve the CR rate in patients with de novo AML, which seems to be related to its beneficial effect on multidrug resistance.

Cyclosporin A combined with vincristine, doxorubicin and dexamethasone (VAD) compared with VAD alone in patients with advanced refractory multiple myeloma: an EORTC-HOVON randomized phase III study (06914)

Patients with multiple myeloma (MM) refractory to alkylating agents frequently express P-glycoprotein (Pgp), which is associated with the multidrug resistance (MDR) phenotype. We have conducted a randomized phase II/III study of the MDR reversal agent cyclosporin A combined with VAD (vincristine, doxorubicin, dexamethasone) compared with standard VAD in patients with MM stage IIA/IIIA who were refractory to or progressive after treatment with alkylating agents. Out of 81 patients who were randomized, 75 were eligible and evaluable: 34 in the VAD + cyclosporin A arm versus 41 in the VAD arm. Toxicities of grade 2-3 were observed more often with VAD + cyclosporin A than with VAD only: nausea (30% versus 8%, P = 0.015), mucositis (18% versus 5%, P = 0.13), infection (45% versus 35%, P = 0.50). The treatment results were similar in the two arms: 53% versus 49% responded [95% CI (-18.5%, 26.9%)]. The median progression-free survival (PFS) was 8.6 months (VAD + cyclosporin A) versus 5.8 months (VAD): [log rank P = 0.16, hazard ratio = 0.71, 95% CI (0.44, 1.15)], and median overall survival was 13 months versus 14.6 months [log rank P = 0.89, hazard ratio = 0.96, 95% CI (0.62, 1.72)]. The cause of death was progressive disease (85%), toxicity (10%) or other (5%). Bone marrow analysis performed in 23 patients showed that the response rate was 67% in Pgp-positive versus 55% in Pgp-negative patients. Cyclosporin A combined with VAD is relatively well tolerated. There is no effect of cyclosporin A on the overall response rate, PFS and overall survival with VAD.

Frequent demonstration of human herpesvirus 8 (HHV-8) in bone marrow biopsy samples from Turkish patients with multiple myeloma (MM)

In order to investigate the frequency of HHV-8 in MM patients from another geographic location, we obtained fresh bone marrow (BM) biopsies from Turkish patients with MM (n = 21), monoclonal gammopathy of undetermined significance (MGUS) (n = 2), plasmacytoma (n = 1) with BM plasma cell infiltration, various hematological disorders (n = 6), and five healthy Turkish controls. The frequency of HHV-8 was analyzed by polymerase chain reaction (PCR) in two independent laboratories in the USA and in Turkey. Using fresh BM biopsies, 17/21 MM patients were positive for HHV-8 whereas all five healthy controls, and six patients with other hematological disorders were negative. Two patients with MGUS, and one patient with a solitary plasmacytoma were also negative. The data from the two laboratories were completely concordant. Also using primer pairs for v IRF and v IL-8R confirmed the results observed with the KS330233 primers. Furthermore, sequence analysis demonstrated a C3 strain pattern in the ORF26 region which was also found in MM patients from the US. Thus, HHV-8 is present in the majority of Turkish MM patients, and the absence of the virus in healthy controls further supports its role in the pathogenesis of MM.

Human herpesvirus 8 open reading frame 26 and open reading frame 65 sequences from multiple myeloma patients: a shared pattern not found in Kaposi's sarcoma or primary effusion lymphoma

Human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus, has been implicated in the pathogenesis of Kaposi's sarcoma (KS), primary effusion lymphoma (PEL), multicentric Castleman's disease, and recently multiple myeloma (MM). DNA sequence analyses of HHV-8 suggest that multiple HHV-8 strains exist. We extracted DNA from 24 patients with MM and 3 patients with monoclonal gammopathy of undetermined significance and compared HHV-8 open reading frames (ORFs) 26 and 65 sequences with those derived from patients with KS, PEL, and two HHV-8-positive PEL cell lines KS-1 and BC-1. ORF26 sequence data suggest that MM patients are consistently carriers of HHV-8 strain subtype C3. All MM patients also consistently revealed either a single bp deletion or substitution at position 112197 in ORF65. This unique alteration is not present in patients with KS or PEL or in PEL cell lines. It occurs in the portion of ORF65 that is known to be responsible for a serological response to HHV-8.

Differences in liver pathology and clinical outcome between two patients with hepatitis B virus and graft versus host disease

Our two patients undergoing allogeneic bone marrow transplantation (AlloBMT) had both Hepatitis B virus (HBV) and graft-versus-host disease (GVHD). In the first patient, liver enzymes elevated three months after AlloBMT, and GVHD was diagnosed. Two weeks after the diagnosis of GVHD, HBsAg appeared in his serum. At that time, liver biopsy was not able to discriminate two disorders, but his sequential liver biopsies disclosed GVHD. Despite the patient was treated with cyclosporin A (CsA), he died for chronic GVHD. In contrast to the first patient, the second patient had HBsAg prior to GVHD. His liver enzymes deterioration was detected in the first month after AlloBMT, and reached the highest level in the third month while withdrawing CsA. In the fifth month he developed scleradermatous skin changes, and skin biopsy revealed chronic GVHD, whereas concurrent liver biopsy revealed chronic active hepatitis. This observation showed that immunosuppressive conditions such as GVHD or its prophylaxis may affect the appearance of liver pathology caused by HBV, which depends on the time of GVHD development, and the duration and depth of GVHD prophylaxis.

Serum erythropoietin levels in patients with leukemia on cytostatic treatment

Anemia is the major stimulus for erythropoietin (Epo) secretion. Various studies have reported increase of Epo following chemotherapy. The mechanism of this phenomenon is not yet clarified. In this study, the serum Epo levels have been evaluated before, during (7 and 14 days), and after (day 25) chemotherapy in patients with acute myeloblastic leukemia (n = 13) and lymphoblastic leukemia (n = 4). As a control group, 12 healthy age-matched subjects were evaluated. Epo levels were high in untreated leukemia patients compared to controls and continued to increase following chemotherapy. There was no significant difference in post-treatment values of Epo as compared with pre-treatment levels. In patients with pre-treatment values of Hb < or = 9 g/dl, Epo levels were inversely correlated with Hb (r = 0.552; p < 0.05). This correlation disappeared during and following treatment. There was no correlation between Epo levels and hematological or biochemical parameters. Therefore, elevated levels of Epo regardless of anemia may be due to a response to tissue hypoxia or increased synthesis of Epo in liver or bone marrow.

Cord blood transplantation (CBT) in hemoglobinopathies. Eurocord

Patients with beta-thalassemia (Hbeta th) and sickle cell anemia (SCA) can be treated with bone marrow transplantation. Stem cells from cord blood have several theoretical advantages, however, the place of cord blood transplant for hemoglobinopathies has not yet been established. We report here the EUROCORD experience of 10 patients (Hbeta th = 7, SCA = 3) transplanted with related cord blood.

Administration of MINE protocol in untreated patients with intermediate and high grade non-Hodgkin's lymphoma

In recent years, more effective and less toxic treatment protocols have been developed to increase the cure rates in intermediate and high grade non-Hodgkin's lymphoma (NHL). This study was undertaken to investigate the efficacy and toxicity of MINE (ifosfamide, mesna, mitoxantrone and etoposide) combination chemotherapy in patients with intermediate and high grade NHL. Twenty-one patients (16 male, 5 female; age between 26 and 70 years) with NHL were included in the study. An overall response rate of 73% and complete response rate of 56% were achieved and survival rate for responding patients was 80% at the 48th month. Side effects including mild myelosuppression, nausea/vomiting and alopecia were observed. MINE combination seems to be effective and well tolerated without significant toxicity as a first-line therapy in patients with intermediate or high grade NHL.

Determination of in vitro drug sensitivity to a panel of cystostatic drugs and interferon alpha-2b in patients with renal cell carcinoma

Fresh operative cells from 27 renal cell carcinomas (RCC) were cultured in vitro for the determination of in vitro drug sensitivity. Two samples were not culturable. Incubation was carried out in triplicate in the presence and absence of various concentrations of chemotherapeutic agents. Sensitivity of the tumour cells to interferon-alpha (IFN-alpha), cisplatin (CDDP), mitomycin C (MMC), vinblastine (VBL), doxorubicin (DOX), etoposide (ETOP), bleomycin (BLM), vincristine (VCR) were tested by a colorimetric assay using MTT. A preexposure viability over 75% was essential for in vitro drug sensitivity assay (IVDSA). Sensitivity was determined by a more than 50 +/- 2 SD% reduction from the control absorbance. All eight drugs in their low concentrations exhibited cell proliferation inhibition in 0-12% of RCCs. On the other hand, IFN-alpha in its higher concentration (60 IU/ml) was effective in 88% of RCCs. After IFN, CDDP was found to be the second most effective drug in its higher concentration (36% efficacy). The results indicate that IFN appears to be the most effective in vitro agent in our 25 RCCs and the clinical trials either as a monotherapy or multiple combinations of various agents should include IFNs for the treatment of RCC.

In vitro drug sensitivity testing of human testicular germ cell tumours with cytostatic drugs and interferon alpha-2b

In spite of the significant advances in the chemotherapy of germ cell neoplasms, some patients do not achieve disease-free status and ultimately die from their diseases. Therefore, it is reasonable to select the best chemotherapeutic agents in these patients by in vitro drug sensitivity assay (IVDSA) in order to apply the most effective agent in case of resistance to primary chemotherapy. Fresh operative cells from 12 testicular germ cell tumours (TGCT) were cultured in vitro. Sensitivity of the tumour cells to interferon-alpha (IFN-alpha), cisplatin, mitomycin C, vinblastine, doxorubicin, etoposide, bleomycin, vincristine (VCR) were tested by a colorimetric assay using MTT. A preexposure viability over 75% was essential for IVDSA. Sensitivity was determined by a more than 50 +/- 2 SD% reduction from the control absorbance. All eight drugs in their high concentrations exhibited cell proliferation inhibition in 83.3 +/- 100% of TGCT. But in low concentrations efficacy of IFN and VCR were found to be lower than the others (33.3% and 58.3%, respectively). The results indicated that although TGCT are highly sensitive to various agents IVDSA may help to identify the effective agents which might be necessary for second line chemotherapy in a small percentage of patients.

A rapid drug sensitivity assay for neoplasmatic cells

A vital dye exclusion method following a 4 day tumor sensitivity assay was used to predict clinical response to chemotherapeutics in 16 patients with acute nonlymphoblastic leukemia (n = 12), acute lymphoblastic leukemia (n = 2), diffuse poorly differentiated lymphoma (n = 1) and oat cell carcinoma (n = 1). After 4 days of incubation, controls and drug-supplied cells were stained with fast green and hematoxylin-eosin. A tumor cell survival of 30% was used to distinguish in vitro resistance and in vitro sensitivity. Eight patients responded and five did not respond to the chemotherapy protocol. This agreed with the in vitro results. Two patients who were sensitive in vitro responded only partially in vivo but two additional patients sensitive in vitro did not respond. These results indicate that this short-term method may give a simple estimation of drug resistance.

Alternating combination chemotherapy does not delay development of refractoriness in myeloma

Sixty-seven patients with stage II and III myeloma were subjected to 3 consecutive prospective phase II studies. Nineteen patients had received melphalan - prednisolone (melphalan group), 17 cyclophosphamide - vincristine - prednisolone (cyclophosphamide group) and 22 alternating combinations of 7 cytostatics and prednisolone (alternating group). Nine patients were unevaluable. The median time until response was achieved was 5, 5 and 3 months respectively. The purpose of the study was to see if combination or alternating combination chemotherapy can delay the appearance of refractoriness. Patients were regarded as refractory after progression, which was defined as advance from stage II to stage III, and, in stage III as an increase of the monoclonal serum protein of more than 25% and/or the monoclonal urine protein of more than 100% despite continued treatment. Refractoriness was not delayed by alternating combination treatment. Thirty per cent of the patients became refractory after 10 months of response in the melphalan group and after 11 months in the cyclophosphamide and the alternating chemotherapy groups. The results remained after stratification for stage.

Effects of retinoids on in vitro differentiation of bone marrow cells in the myelodysplastic syndrome

The effect of retinoids on cell differentiation in the myelodysplastic syndrome was studied in short-term liquid cultures of bone marrow from 13 patients. After incubation with 13-cis-retinoic acid there was a significant decrease in the percentages of promyelocytes and in Leu-M3-binding cells. Lue-M3 is mainly a monocyte marker, and retinoids thus seem to induce a shift from monocytoid to myeloid differentiation. Patients with refractory anemia with an excess of blasts responded the most, and did also show a significant decrease in OKIa1-binding cells. Etretinate, on the other hand, did not show any differentiation-inducing activity. The results support earlier reports that retinoic acid might be useful in the treatment of the myelodysplastic syndrome. Whether this in vitro technique offers a possibility to predict the clinical outcome remains to be shown.