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Biomedical subjects

R A Kyle

Publications and source records attributed to R A Kyle.

At least 37 records · Page 2Linked to original sources
PubMed2001

A high bone marrow plasma cell labeling index in stable plateau-phase multiple myeloma is a marker for early disease progression and death.

The plasma cell labeling index (PCLI) is a measure of plasma cell proliferative activity and is an important prognostic factor in newly diagnosed multiple myeloma (MM). Occasionally patients have been observed with stable, plateau phase MM with minimal numbers of residual light-chain-restricted monoclonal plasma cells, but a high PCLI. No data are available on the outcomes for such patients. Data from 57 patients with plateau phase MM and a marrow PCLI of more than 1.0% were compared with 105 matched control patients with MM with a marrow PCLI of less than 1.0%. All patients had less than 10% total plasma cells on marrow aspirate and biopsy. The median time to progression and overall survival were 8 months and 20 months, respectively, in the high PCLI group versus 39 months and 56 months, respectively, in the low PCLI group (P < .0001). These findings suggest that a high PCLI in patients with apparently stable, plateau phase MM is an adverse parameter that may predict a short time to disease progression and death.

Bone Marrow↗
PubMed2001

Clonal evolution in Waldenstrom macroglobulinemia highlights functional role of B-cell receptor.

The course of clonal evolution of 2 related clones in the blood of a patient with Waldenstrom macroglobulinemia (WM) indicates the functional importance for the expression of the B-cell receptor for the survival of these malignant cells. Protein and nucleotide sequencing of the paraproteins' variable regions revealed 2 predominant Vlambda and 2 VH sequences, each set comprised in the ratio 1:1.5. The 2 VH sequences and 2 Vlambda sequences shared the same VDJ and VJ junctional sequences, respectively, indicating that 2 malignant clones had evolved from a common ancestor. This is the first report on intraclonal heterogeneity in WM. Comparison of the Vlambda and VH sequences with the closest matching known germline genes showed that they contained approximately 10 somatic mutations each. The distribution and type of mutations demonstrate that mutations have continued to accumulate in the malignant clones and that selection has been operating to preserve immunoglobulin structure.

Base Sequence↗
PubMed2001

Methods for estimation of bone marrow plasma cell involvement in myeloma: predictive value for response and survival in patients undergoing autologous stem cell transplantation.

In myeloma, the bone marrow plasma cell percentage (BMPC%) is usually estimated independently on the aspirate, core biopsy, and plasma cell labeling index (PCLI) samples. This study was done to determine which of the 3 individual estimates correlates best with complete response (CR) and survival. Seventy-five consecutive patients who underwent SCT for relapsed myeloma were studied. The median BMPC% on the marrow aspirate, core biopsy, and PCLI studies were 20, 25, and 20, respectively. There was a significant correlation between the three methods, rho > 0.65, P < 0.001. However, in 8% of patients the BMPC% was different by an absolute value of 50% between methods. No individual method was predictive for CR. However, the highest estimate of the BMPC% among the three methods was a significant predictor of CR (P = 0.02). Survival following SCT was longer among patients with a low BMPC% (< or =60) by the PCLI method compared to those with higher values, median survival 23 versus 7 months, respectively, P = 0.02. PFS was also different, with survival times of 11 and 5 months, respectively, P = 0.003. Similar results were obtained when the highest estimate of the BMPC% was used in survival analysis (P = 0.02 and 0.004, respectively). Statistical significance was lower when the BMPC% on the aspirate or biopsy used in survival analysis. Compared to any individual method of estimating BMPC%, the highest estimate of the BMPC% is the best predictor of CR in myeloma. It is also prognostic for poor survival and PFS following SCT for myeloma. We recommend that all three methods of estimating BMPC% be routinely performed and that the highest value be used for prognostic purposes.

Adult↗
PubMed2001

Primary systemic amyloidosis: a cause of malabsorption syndrome.

PURPOSE: Although malabsorption syndrome is encountered frequently by general internists and gastroenterologists and is common to various underlying disease processes, primary amyloidosis is often overlooked during medical evaluation. We describe the diagnosis, natural history, and laboratory features of a subgroup of patients with primary amyloidosis who presented predominantly with gastrointestinal symptoms and with evidence of a malabsorption syndrome. SUBJECTS AND METHODS: We reviewed all patients diagnosed with amyloidosis and malabsorption syndrome who had been seen at the Mayo Clinic from 1960 through 1998. Nineteen patients with small bowel biopsy results showing primary amyloid and with laboratory evidence of a malabsorption syndrome were studied. RESULTS: The most common symptoms were diarrhea or steatorrhea in 95% of patients (n = 18), anorexia in 42% (n = 8), and dizziness in 32% (n = 6). The most common signs included weight loss in all 19 patients, with a median weight loss of 30 pounds (range, 2 to 134 pounds) and hypotension or orthostatic changes in 10 patients (53%). The median time from symptom onset to diagnosis was 7 months. Most patients had evidence of amyloid involvement of other organs. Only 3 patients (16%) were diagnosed correctly upon initial presentation. Serum or urine protein electrophoresis results were positive in 95% of patients (n = 18). Median survival was 11 months from histologic diagnosis. CONCLUSIONS: Primary systemic amyloidosis should be considered in the differential diagnosis of malabsorption syndrome. All patients over 30 years of age with a malabsorption syndrome should have screening serum and urine immunofixation before undergoing a small bowel biopsy.

Adult↗
PubMed2001

Multiple Myeloma. Diagnostic challenges and standard therapy.

In the diagnosis of multiple myeloma (MM), the clinician must exclude other disorders in which a plasma cell reaction may occur such as rheumatoid arthritis and connective tissue disorders, or metastatic carcinoma where the patient may have osteolytic lesions associated with bone metastases. Patients with smoldering multiple myeloma (SMM) or monoclonal gammopathy of undetermined significance (MGUS) have none of the complicating features of MM and do not require treatment with potentially toxic agents. The plasma cell labeling index can help make a differential diagnosis of MM from SMM. Patients with a high labeling index have a high risk of complications and should be monitored carefully. However, the labeling index can be low in active MM. In addition, SMM or MGUS patients have few or no circulating plasma cells. High-dose chemotherapy and stem cell support prolong overall survival in contrast to conventional therapy. If stem cell transplantation is considered, it is important to harvest the cells before using alkylating agents to obtain a sufficient number of cells. Supportive treatment consists of the occasional use of erythropoietin to maintain adequate hemoglobin levels and adequate hydration to protect renal function. Vaccination against pneumococcal infections and the prophylactic use of antibiotic therapy during the first 2 months of treatment can be beneficial. Recognizing the symptoms of spinal cord compression and initiating dexamethasone therapy promptly to prevent paraplegia are critical.

Antineoplastic Agents↗
PubMed2001

Angiogenesis in multiple myeloma.

Angiogenesis is the process of new blood vessel formation, and normally occurs during embryonal growth, wound healing, and the menstrual cycle. It is essential for the proliferation and metastases of most malignant neoplasms. There is now growing evidence that angiogenesis is increased and is likely important in multiple myeloma. Recent evidence suggests that angiogenesis is greater in multiple myeloma compared to monoclonal gammopathy of undetermined significance (MGUS). Angiogenic cytokines such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) are expressed by neoplastic plasma cells, and may play a role in the increased angiogenesis seen in myeloma. In a study of 400 patients with plasma cell disorders, microvascular density (MVD) was significantly higher in smoldering myeloma, newly diagnosed myeloma, and relapsed myeloma compared to controls, MGUS, and primary amyloidosis. In another study involving 74 newly diagnosed patients with myeloma treated at the Mayo Clinic, overall survival was significantly longer in patients with low-grade angiogenesis compared to those with high-grade or intermediate-grade angiogenesis. The finding of increased angiogenesis in myeloma provides the rationale for the study of antiangiogenic therapy in this disease.

Angiogenesis Inhibitors↗
PubMed2001

Therapeutic application of thalidomide in multiple myeloma.

Treatment with thalidomide and dexamethasone was given to 26 patients with active, previously untreated multiple myeloma (MM). Thalidomide was administered in an initial dosage of 200 mg/d for 2 weeks and then increased as tolerated (in 200-mg increments at 2-week intervals) to a maximum daily dose of 800 mg. Dexamethasone was given orally in a dosage of 40 mg/d on days 1 through 4, 9 through 12, and 17 through 20 in odd cycles and 40 mg/d on days 1 through 4 in even cycles at monthly intervals. Response was defined as a decrease in serum and urine monoclonal (M)-protein by 50% or greater. Twenty (77%) of 26 patients with active MM exhibited a therapeutic response. Among the first seven patients treated with a thalidomide dose of 400 mg, grade III to IV skin toxicity developed in two. Drug titration was then stopped and the thalidomide dose maintained at 200 mg/d. Six (86%) of seven patients showed a response after thalidomide dose escalation, whereas 14 (74%) of 19 patients demonstrated a response with a constant thalidomide dose of 200 mg/d. Thalidomide alone produced a response in six (38%) of 16 patients with smoldering or indolent myeloma. The angiogenesis grade was elevated in only 8% of these patients. Thirty-two patients with relapsed myeloma were treated with thalidomide dosed at 200 mg/d, with 200-mg escalations every 2 weeks to a maximum daily dose of 800 mg. Prior chemotherapy had failed and five (16%) patients had experienced relapse following stem cell transplantation. Ten (38%) of the 26 patients who had received at least two cycles of therapy obtained a response.

Angiogenesis Inhibitors↗
PubMed2001

Thalidomide for previously untreated indolent or smoldering multiple myeloma.

We conducted a clinical trial of thalidomide as initial therapy for asymptomatic smoldering (SMM) or indolent multiple myeloma (IMM). Sixteen patients were studied. Thalidomide was given orally at a dose of 200 mg/day for 2 weeks, and then increased as tolerated by 200 mg/day every 2 weeks to a maximum dose of 800 mg/day. Bone marrow microvessel density (MVD) and angiogenesis grading were estimated using CD34 immunostaining. Six patients had a confirmed response to therapy with at least 50% or greater reduction in serum and urine monoclonal (M) protein. When minor responses (25-49%) decrease in M protein concentration) were included, 11 of 16 patients (69%) responded to therapy. Major grade 3-4 toxicities included two patients with somnolence, and one patient each with syncope and neutropenia. Pre-treatment MVD was not a significant predictor of response to therapy, median MVD 4 and 12 in responders and non-responders respectively, P = 0.09. We conclude that thalidomide has significant activity in the treatment of newly diagnosed SMM/IMM. However, we do not recommend treatment with thalidomide at this stage since some patients with SMM/IMM can be stable for several months or years without any therapy. Additional randomized trials are needed to determine if thalidomide will delay progression to active multiple myeloma.

Administration, Oral↗
PubMed2001

Pulmonary marginal zone lymphoma of MALT type as a cause of localised pulmonary amyloidosis.

AIM: To describe six patients with pulmonary marginal zone lymphoma in whom amyloid deposition was identified. Marginal zone lymphoma is a recently recognised type of low grade non-Hodgkin's lymphoma. METHODS: A computerised search was performed of all patients seen at the Mayo Clinic with a diagnosis of pulmonary amyloidosis. Six patients with pulmonary amyloidosis who had biopsy confirmed extranodal marginal zone lymphoma of mucosa associated lymphoid tissue type were identified. All were women, ranging in age from 45 to 85 years. RESULTS: Five patients had amyloid deposition in conjunction with pulmonary marginal zone lymphoma at the time of the original diagnosis. One patient was referred for evaluation of localised pulmonary amyloidosis and was found to have coexisting pulmonary marginal zone lymphoma. Clinical presentation was limited to pulmonary symptoms (two of the six) or constitutional symptoms (two), or was asymptomatic (two). In all six cases, initial findings of nodular densities on screening chest roentgenograms led to further evaluation and eventual lobectomy; these findings included multiple pulmonary nodules (four), single nodule (one), and single nodule with diffuse bilateral interstitial infiltrates (one). Bone marrow was examined in five patients and was normal in all. Protein studies performed in four patients revealed no monoclonal protein. No patients had manifestations of systemic amyloidosis, such as renal, neurological, or cardiac involvement, at a median follow up of 50 months. Four of the six patients remain alive at a median of five years. CONCLUSIONS: Pulmonary marginal zone lymphoma may be found in association with localised amyloid deposition and should be considered in the differential diagnosis of localised pulmonary amyloidosis.

Aged↗
PubMed2001

Primary lymph node plasmacytomas (plasmacytic lymphomas).

To determine whether primary lymph node plasmacytoma (PLNP) is a distinct entity among other types of plasma cell neoplasia, we analyzed a large series of PLNPs from 2 large lymphoma registries to compare histologic, immunophenotypic, and clinical features of PLNPs, nonnodal extramedullary plasmacytomas, and multiple myeloma. Twenty-five PLNPs (clinical data on 15 cases) were compared with 10 non-lymph node plasmacytomas and 51 cases of multiple myeloma; 36 cases of reactive plasmacytoses were used as controls. The histologic features of PLNP and other extramedullary plasmacytomas were similar. The histologic features of PLNPs were more immature than those of reactive plasmacytoses and less immature than in multiple myeloma. The immunophenotype of PLNPs significantly differed from that of reactive plasmacytoses, other extramedullary plasmacytomas, and multiple myeloma. PLNPs did not progress to multiple myeloma, unlike other extramedullary plasmacytomas, even though survival in PLNPs and other extramedullary plasmacytomas was similar. Our findings suggest that PLNPs may be distinct from other plasma cell dyscrasias.

Adolescent↗
PubMed2001

Update on the treatment of multiple myeloma.

The patient with multiple myeloma should be carefully evaluated from the standpoint of symptoms, physical findings, and laboratory data. If there are no symptoms or evidence of early or impending complications, the patient should not be treated. He or she should be followed and treatment delayed until progression of the disease occurs. If the patient is younger than 70 years, autologous peripheral blood stem cell transplantation should be considered. Hematopoietic stem cells should be collected before the patient is exposed to alkylating agents. If the patient is older than 70 years, chemotherapy is indicated. The two major shortcomings of autologous stem cell transplantation are: A) failure to eradicate myeloma, and B) contamination of autologous peripheral blood stem cells. Most physicians initially treat the patient with vincristine, doxorubicin (Adriamycin), and dexamethasone (VAD) for three to four months and then collect the peripheral blood stem cells. One can then proceed with transplant or treat the patient with alkylating agents and delay the transplant until the patient progresses. In a prospective trial comparing autologous bone marrow transplantation with conventional chemotherapy, five-year overall survival favored the transplant group (52% versus 12%). In a randomized trial of 400 patients from France, there was no difference in event-free or overall survival between double and single autologous stem cell transplant when evaluated at two years. In a subsequent evaluation, patients with a low beta(2)-microglobulin value at diagnosis appeared to have better results with a double transplant. There is no evidence that combinations of chemotherapeutic agents are more effective than melphalan and prednisone. Allogeneic transplantation is associated with a high mortality. Depletion of T-cells or a mini-allogeneic transplant may be beneficial in an effort to reduce mortality. Thalidomide produces objective response in approximately 30% of refractory patients. The use of intravenous bisphosphonates is recommended for patients with skeletal lesions. Hypercalcemia and renal failure must be treated promptly.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

Management of patients with multiple myeloma: emphasizing the role of high-dose therapy.

Treatment for multiple myeloma should not be given until the patient is symptomatic or at risk for the occurrence of complications of the disease. If the patient is younger than 70 years, the physician should seriously consider an autologous peripheral blood stem cell transplant. Most physicians initially administer vincristine/doxorubicin/dexamethasone (VAD) for 3 to 4 months and then collect the stem cells before exposure to alkylating agents. Following stem cell collection, one may proceed with high-dose chemotherapy and then infusion of the stem cells, or one can administer alkylating agents until a plateau is reached and delay transplantation until progressive disease occurs. There is no difference in overall survival between early and late transplantation, but the former avoids the cost and inconvenience of alkylating agent therapy. Double or tandem autologous stem cell transplants may produce better results, but the evidence is not strong. Almost all patients have a relapse after an autologous stem cell transplant, so efforts are being made to prolong the response with a2-interferon or dendritic cell therapy. Allogeneic bone marrow transplantation is feasible for only 5%-10% of patients, but the mortality is high and it is curative in only a small fraction of patients. Treatment with melphalan and prednisone results in an objective response in 50%-60% of patients. Combinations of alkylating agents produce a higher response rate, but there is no survival benefit. Thalidomide produces an objective response in about one third of patients with refractory disease. It currently is being studied in conjunction with dexamethasone for conventional initial therapy.

Adult↗