Behaviour of chemical elements during weathering of pyroclastic rocks, Hong Kong.

The behaviour of whole-rock major, trace and rare earth elements (REE) during weathering under subtropical conditions is examined along a profile developed over crystal--vitric tuffs with eutaxitic texture. The intensity of weathering within the profile varies erratically, indicating weathering processes operate over different scales. Quartz, K-feldspar, plagioclase and biotite are the main primary minerals, whereas clays, sesquioxides, sericite and chlorite are the alteration products. Kaolinite, halloysite and illite-mica are the dominant clay minerals present in significantly varying proportions. Two competing processes, namely leaching and fixation, are the main regulators of variations in mostly major and some trace element concentrations along the profile. In general, as the intensity of weathering increases, Ca, Na, K, Sr +/- Si decrease, while Fe, Ti, Al and loss of ignition (LOI) increase. Likewise, the intensity of negative Eu-anomaly decreases while the intensity of negative Ce-anomaly and the La/Lu and Sm/Nd ratios increases. In detail, however, the behaviour of chemical elements cannot be solely explained in terms of the degree of weathering. This study makes it clearly evident that the type and abundance of sesquioxides and clay minerals can significantly modify the geochemical signatures of weathering processes.

A randomized trial of maintenance interferon following high-dose chemotherapy in multiple myeloma: long-term follow-up results.

High-dose chemotherapy (melphalan) with autologous marrow stem cell support (AMSCS) results in high response rates in multiple myeloma (MM), with up to 50% of patients achieving complete remission. However, these remissions are generally not durable. As the cytokine interferon alpha has been shown to prolong partial response following conventional chemotherapy, this trial was conducted to evaluate its role following high-dose chemotherapy. 85 patients were randomly assigned to maintenance treatment with interferon alpha, 3 x 10(6) units/m2 subcutaneously three times weekly until relapse or no further treatment following recovery from high-dose chemotherapy (melphalan 140-200 mg/m2 or busulphan 16 mg/kg) combined with AMSCS. At 5.8 years following the accrual of the last patient in this trial, 38 patients had died, 17 in the interferon arm and 21 in the control arm. The median progression-free survival (PFS) in the 42 patients randomized to interferon alpha was 46 months versus 27 months in the controls. Both overall survival and PFS, which were highly significant at median follow-up of 52 months, have now ceased to be significant, because most patients have ultimately succumbed to their disease. Interferon was tolerated by the majority of patients with very good compliance. Toxicity consisted mainly of flu-like symptoms and malaise which were usually self-limiting. The results of such a pilot study should be carefully interpreted and the benefits of interferon should be confirmed in larger multicentre studies in the setting of minimal residual disease following autologous transplantation.

Langerhans cell histiocytosis in adults.

Langerhans cell histiocytosis in the adult is rare, but it is important to recognize its occurrence, as it must be differentiated from lymphoma, myeloma, and a variety of skin conditions and endocrinopathies. It has been reported in patients up to the ninth decade of life, and occurs equally in men and women. Local disease has a good prognosis, but associated diseases--particularly malignancy--may be the cause of death in some adults. The optimal treatment is not known. Coordinated investigation of the epidemiology and therapy of this disease is needed.

Langerhans cell histiocytosis in the adult.

A study of 47 well-documented patients with Langerhans cell histiocytosis (LCH) showed a slight female preponderance, with onset as late as the ninth decade. The skin was the commonest site of presentation, but pulmonary and bone involvement was frequent. Patients with single-site disease did best. The worst prognosis was seen in the elderly or those with organ dysfunction. A high incidence of associated malignant disease was seen, which could precede, be coincidental with, or occur after a diagnosis of LCH.

The use of 99mTc-MIBI scanning in multiple myeloma.

Tc-99m 2 methoxy-isobutyl-isonitrile (99mTc-MIBI), also called Sestamibi, is a safe and effective scanning agent in solid tumours. Its use in imaging lesions in multiple myeloma has been studied in 21 patients with either multiple myeloma (19/21) or monoclonal gammopathy of undetermined significance (MGUS) (2/ 21). 99mTc-MIBI scanning was positive in 14 patients, 13 with active myeloma and one patient with MGUS showing possible transformation to a more accelerated phase. In seven patients 99mTc-MIBI scanning was negative. In four of them, the result was unexpected, as they had the features of active myeloma. All four were either primarily or secondarily resistant to chemotherapy, with high total cumulative doses of doxorubicin. Overexpression of P-glycoprotein associated with multidrug resistance could be a factor, as it has been shown that 99mTc-MIBI is actively eliminated from the cell by P-glycoprotein. With this assumption, sensitivity of the scanning technique in this series is 100%, and the specificity 88%. No toxicity was experienced by any patient. 99mTc-MIBI scanning is a useful adjunct to the investigation of multiple myeloma, and may have potential as an in vivo test for multidrug resistance.

Maintenance therapy for remission in myeloma with Intron A following high-dose melphalan and either an autologous bone marrow transplantation or peripheral stem cell rescue.

Eighty-four patients with myeloma were randomized to receive maintenance Intron A (Schering-Plough, Suffolk, UK), 3 mega units/m2 s.c. three times weekly or no treatment following induction therapy with cyclophosphomide, vincristine, doxorubicin, methyl prednisolone (C-VAMP), consolidated with high-dose melphalan (HDM) 200 mg/m2 + autologous bone marrow transplantation (ABMT). The patients have been followed up for a median of 52 months. Overall, median progression-free survival (PFS) from HDM was 27 months in the control group and 46 months in the Intron A group (< 0.025). For the 65 patients who achieved complete remission (CR) with HDM, there was a significant prolongation of remission (p = 0.02) for those who received Intron A and 49% of these patients remained in remission four years after high-dose treatment. However, for partial responders (PR) and nonresponders to HDM there was no significant prolongation of PFS. Overall, survival was also significantly better for the Intron A group, with 5 deaths versus 14 deaths in the control group (p = 0.006). Subsequently, 54 consecutive patients received the same HDM followed by rescue with peripheral blood stem cells after induction chemotherapy which included C-VAMP. Intron A was started in 45 of these patients at a median of 62 days which was comparable to the ABMT arm. The overall response rate in these patients was 79.62% (43/54-CR+PR) and the probability of survival at 18 months was 74.2% by the Kaplan Meier method.(ABSTRACT TRUNCATED AT 250 WORDS)

Quality of life in survivors of childhood cancer after megatherapy with autologous bone marrow rescue.

A questionnaire study was carried out in a group of survivors of childhood cancer to assess their quality of life. The questionnaire was sent to 30 survivors who had completed treatment with megatherapy followed by autologous bone marrow rescue at St Bartholomew's Hospital, London. Of the 28 respondents (93%), in 27 (96%) the quality of life was judged to be good, with 11 of these 27 (40%) having no disability whatsoever and a further 9 (33%) reporting only minimal disability. The other 7 patients had moderate to severe disabilities, with pain and depression remaining ongoing problems, and some adolescents felt that they were unable to cope with everyday life alongside their peers. Nine parents and 14 of the children themselves expressed anxiety about the previous illness. The study shows that, by using a postal method, a satisfactory assessment of quality of life in survivors of childhood cancer can be made.

Vincristine and oral etoposide in refractory multiple myeloma.

A total of 15 patients with refractory multiple myeloma (MM; 4 primary unresponsive and 11 relapsed and resistant to re-induction/salvage therapy) received i.v. vincristine on day 1 and oral etoposide daily for 4 days, the treatment being repeated at 3-weekly intervals. The patients were re-assessed after three cycles of chemotherapy, and non-responders received no further therapy. There was no complete or partial response. A minimal response was seen in two patients, and two others showed stable disease. None of the responses was sustained, and all patients eventually had progressive disease. It is concluded that combination chemotherapy with vincristine and oral etoposide given by this schedule is unlikely to be of any value in refractory myeloma.

Myeloma during a decade: clinical experience in a single centre.

One hundred and fifty-six patients with multiple myeloma were treated over a period of 12 years at St. Bartholomew's Hospital. The progress of the disease was affected in 96/156 patients (61%). Response was defined as achieving a plateau of M component. A partial or complete response was seen in 68/120 patients treated conventionally (56.5%), and in 28/36 patients treated with high-dose therapy (77.7%). The median survival of the group as a whole was 20 months, with a 2-year survival of just over 40%. In the 36 patients treated with high-dose therapy, median survival was 6 years, and in a small group who have had maintenance Interferon therapy, the median has not yet been reached. In a univariate analysis, age, intensity of therapy, haemoglobin and creatinine levels were significant, but multivariate analysis showed that only age and intensity of therapy were independent predictors for survival. The outlook for relapsed patients who showed progression of disease remains poor, but palliation was best achieved by steroid and Interferon in combination. Patients who achieve complete responses and are maintained on Interferon appear to be doing better both in terms of freedom from symptoms and in survival, and methods to enable an elderly population to tolerate this form of therapy need to be explored.

High-dose melphalan and autologous bone marrow transplantation as consolidation in previously untreated myeloma.

PURPOSE: We report the results of intensive chemotherapy with high-dose melphalan (HDM) following conventional-dose cytoreductive chemotherapy in previously untreated patients with myeloma. PATIENTS AND METHODS: From 1986 to 1991, 53 previously untreated patients with myeloma received HDM 200 mg/m2 plus methylprednisolone 1.5 g daily (MP) for 5 days with autologous bone marrow transplantation (ABMT) after cytoreductive chemotherapy. RESULTS: At the time of HDM administration, responses to induction therapy were complete remission (CR) in nine patients, partial remission (PR) in 38, and no response (NR) in six. Following HDM, all but one patient responded, with 40 patients achieving a CR (75%). There was one treatment-related death following HDM. The median time to reach a WBC count more than 1,000/microL and platelet count more than 25,000/microL was 19 days (range, 13 to 30) and 24 days (range, 15 to 55), respectively. The median duration of response has not been reached at 20 months, and it is significantly longer for patients in CR than for those in PR (P < .025). Currently, with a median follow-up duration of 31 months (range, 6 to 58), 12 patients are dead and 40 are alive, and the estimated probability of survival at 54 months is 63%. Multivariate analysis found hemoglobin (Hb) more than 10 g/dL (P = .012), and stage A disease (P = .001) at diagnosis to be favorable indicators for survival. CONCLUSION: Myeloma patients who are able to receive HDM plus ABMT following conventional chemotherapy achieve a high proportion of CRs, which may be associated with prolonged survival.

High-dose melphalan for multiple myeloma: long-term follow-up data.

PURPOSE: To present long-term follow-up data of patients with myeloma treated with high-dose melphalan HDM, including an assessment of prognostic factors. PATIENTS AND METHODS: Between November 1981 and April 1986, 63 previously untreated patients with multiple myeloma received HDM 140 mg/m2 without autologous bone marrow transplantation. RESULTS: The overall response rate was 82% (51 of 62), with 32% (20 of 62) patients entering complete remission (CR). The median duration of response was 18 months, and six patients remain alive and free from disease progression at 60+ to 84+ months. Improvements in quality of life associated with remission were immediate in terms of pain grade (89% of patients) and performance status (92%), and later in terms of bone healing (29%). Currently, at a median follow-up duration of 74 months (range, 63 to 100) since HDM, 23 patients are alive with a median survival duration of 47 months, and 35% of patients are expected to be alive at 9 years. Apart from early-stage disease, no factors were found to predict long-term survival. No second malignancies or other late side effects have been recorded. CONCLUSION: Single-agent HDM without autologous bone marrow transplantation is a feasible therapeutic option in myeloma, and is associated with a high objective response rate, relatively long remission durations, and good symptom control.

Some aspects of cancer medicine.

The role of molecular oncology in understanding the nature of the cancer cell, and as an aid to diagnosis and even therapy, is discussed and illustrated with examples from commonly occurring malignancies. The appreciation of the importance of cell biology in explaining why cells become resistant to anticancer drugs has developed rapidly, and examples are given. Cell biology and molecular biology contribute to cancer prevention, which is becoming a practical possibility. Haemopoietic growth factors make it possible to give more intensive chemotherapy treatments and to improve the survival rate in patients with chemoresponsive disease. Intensification, however, has to be balanced against the risk of both short-term and, more seriously, long-term toxicity.

Testicular function following the treatment of Hodgkin's disease in childhood.

Testicular function was studied in 40 males treated in childhood for Hodgkin's disease at St Bartholomew's Hospital, and the Hospital for Sick Children, London, between 1971-1985. All patients were 16 years or over at evaluation, and off treatment more than 6 years. Basal FSH, LH and testosterone levels were measured. Testicular size was measured using a Prader orchidometer, and all patients were offered a seminal analysis. Twenty-eight patients were treated with chemotherapy, usually ChlVPP. Twenty-one also had radiotherapy, five below the diaphragm. Twelve patients were treated with radiotherapy alone (five below the diaphragm). Twenty-six of 28 patients treated with chemotherapy and three of five patients treated with radiotherapy alone below the diaphragm have elevated basal FSH levels, and 18 of these also have elevated basal LH levels. Median testicular volume is 11 ml (range 5-25 ml). Eleven of 13 patients investigated are azoospermic. All patients have normal testosterone levels, and normal secondary sexual characteristics. There is no biochemical evidence of healing of the damaged germinal epithelium with elevated FSH levels persisting up to 17 years from the end of therapy. These results indicate a high incidence of damage to the germinal epithelium in patients treated with ChlVPP chemotherapy and/or radiotherapy below the diaphragm. Appropriate counselling of these patients with regard to their reproductive capabilities is essential.

Recombinant interferon-alpha 2b and high dose methyl prednisolone in relapsed and resistant multiple myeloma.

Twenty-one patients with refractory myeloma (10 primary resistant and 11 relapsed resistant) were treated with a combination of high dose methyl prednisolone and recombinant interferon alpha 2b (IFN-alpha 2b). This treatment included three megaunits/m2 of IFN-alpha 2b three times a week for 12 weeks, plus 5-day pulsed high dose methyl prednisolone every 3 weeks for two courses. A partial response (more than 50 per cent reduction in paraprotein) was observed in six patients; two of these had a greater than 75 per cent reduction in paraprotein, and evaluation of bone marrow showed <5 per cent plasma cells. A minimal response (more than 25 per cent reduction in paraprotein) was seen in four patients, giving an overall objective response rate of 10/21 (48 per cent). Subjective response, in terms of subsidence of pain and improvement of performance status, was seen in all patients who had adequate therapy. The protocol was generally well tolerated with minimal side-effects. There were 4/21 (19 per cent) treatment-related deaths which, though considerable, was anticipated in such a study population. The excellent subjective response seen supplements the objective response observed, and suggests a potential role for the combination of methyl prednisolone and IFN-alpha 2b in refractory myeloma.