Masahiko Kondo

Clinical Study of Brain Metastasis of Renal Cell Carcinoma

Objectives: To evaluate the natural history and the efficacy of treatments for renal cell carcinoma (RCC) with brain metastasis, we reviewed 18 patients with this disease. Methods: Out of 325 cases with RCC treated at Osaka University Hospital from 1957 to 1993, 18 (5.5%, male:female ratio 16:2) cases developed brain metastases. Median follow-up was 44 months after the initial treatment of the primary lesion. Twelve patients had surgical resection of brain metastases (surgical group), and 7 of them received adjuvant radiotherapy. Six patients with poor performance status were treated with supportive therapy alone (nonsurgical group). Results: Of 18 RCC patients with brain metastasis, 16 were male and 2 female. All brain metastases except for 1 case were symptomatic. Median interval between the initial treatment of the primary lesion and the diagnosis of brain metastasis was 19 months. The most frequent metastatic site prior to brain was the lung, which was detected in 7 cases (38.9%). Median survival of the entire group, measured from the onset of brain metastasis, was 9.5 months. One-year survival rate after the diagnosis of brain metastasis was 43.2% (64.8% in surgical group, 0% in nonsurgical group), 3-year 18.5% and 5-year 0%. Among 109 metastatic RCC, 14 patients were treated by lymphokine-activated killer (LAK) therapy. Out of 14 metastatic RCC patients treated by LAK therapy, 3 (21.4%) developed brain metastases. On the other hand, out of 95 metastatic RCC patients without LAK therapy, 15 (15.8%) had brain metastases. There was no significant difference in the rate of brain metastases between these two groups. Conclusion: There was a trend for prognosis of the surgical group to be better compared to that of the nonsurgical group, although it is not statistically significant. The optimum treatment for brain metastasis of RCC remains undefined, but our data suggested surgical resection in selected patients might contribute to prolonged survival of patients with brain metastasis. LAK therapy was not necessarily the risk factor of the brain metastasis.

Enhancement of interleukin-2-induced lymphokine-activated killer activity by interleukin 7 against autologous human renal cell carcinoma.

Adjuvant immunotherapy with interferons and/or interleukin 2 (IL-2) is widely used for advanced kidney cancer. However, the results are not satisfactory so far. The purpose of this study is to evaluate the inducible activity of lymphokine-activated killer (LAK) cells against autologous human renal cell carcinoma. The effect of interleukin 7 (IL-7) on IL-2-induced LAK activity was assessed by the autologous assay system which we have established. Peripheral blood lymphocytes from patients with renal cell carcinoma were stimulated with IL-2 and/or IL-7, and tested for antitumor activity against autologous renal cell carcinoma. In all 10 cases tested, IL-7 alone induced LAK activity. Moreover, IL-2-induced LAK activity was augmented by the concomitant addition of IL-7. Flow cytometry revealed an increase in IL-2-receptor-positive lymphocytes following incubation with IL-7. These results suggest that combination therapy using IL-2 and IL-7 may be a useful treatment for patients with advanced renal cell carcinoma.

A Study on LPE Growth of In1-xGaxP1-yAsy(y ≃0) on (100) GaAs Substrate

The growth conditions have been studied in detail for InGaPAs LPE layers grown on (100) GaAs substrates using the two-phase melt technique. The accurate liquidus isotherms and iso-concentration curves have been obtained experimentally and are compared with the calculated ones. It has been found that the area of the successful growth of InGaPAs on GaAs shifts according to the degree of supercooling. The influences of variations of the As atomic fraction in the liquid, XAsl, on the liquidus and solidus compositions have also been investigated in detail. The diffusion coefficients of P and Ga in an In-rich melt at 800°C have been determined as 1.9×10-4 and 1.8×10-4 cm2/s, respectively. The influence of the degree of supercooling on crystal growth is discussed using a mass transport analysis in both liquid and solid phases, together with the equilibrium phase diagram.

LPE Growth of In1-xGaxP0.96As0.04 on GaAs Substrate by Two-Phase Melt Method.

In1-xGaxP0.96As0.04 LPE layers were grown on (100) GaAs substrates from a two-phase solution with an excess GaP source at 785°C and 795°C. The relations between the liquid compositions of Ga and P, XGal and XPl, at 800°C, were obtained experimentally for a liquid composition of As, XAsl, of 0.76 at%. Based on these results, it was found that high-quality InGaPAs LPE-layers can be grown from an In melt with XGal between 1.10 at% and 1.30 at% and XPl between 2.85 at% and 2.90 at%. The liquid and solid compositions are discussed in connection with the calculated In-Ga-P-As phase diagram. The characteristics of the solution were examined by changing the growth time and temperature, and the crystal quality of the InGaPAs LPE layers was examined by a photoluminescence method in terms of the lattice mismatch between the InGaPAs LPE layer and the GaAs substrate

Characterization of interface stress at InGaPAs/GaAs by Cr-related luminescence line in GaAs

The interface stress at InGaPAs/GaAs heterostructure has been investigated using the energy shift and splitting of the Cr-related zero-phonon photoluminescence line at 0.839 eV observed in GaAs. It has been found that the GaAs substrate suffers both compressive uniaxial stress and tensile hydrostatic pressure at the InGaPAs/GaAs heterointerface. These shifts and splittings of the 0.839 eV line have been systematically examined as a function of the lattice mismatch between InGaPAs and GaAs, and the thicknesses of the epitaxial-layer and substrate. The amount of the interface stress existing at InGaPAs/GaAs heterostructure has been estimated, based on uniaxial stress data for GaAs: Cr wafers.

Influence of immiscibility in liquid‐phase epitaxy growth of InGaPAs on GaAs

The liquid‐phase epitaxy (LPE) growth of InGaPAs grown on (100) GaAs substrate has been studied under various growth conditions over the whole solid composition range. It has been found that the degree of supercooling less than 5 °C is necessary to successfully grow InGaPAs LPE layers in the composition region influenced by immiscibility, and that the extraordinary broadening of their photoluminescence spectra is attributed to a large number of defects and dislocations included in them. The role of the elastic energy induced from a substrate is discussed on a basis of the experimental results of the InGaPAs LPE growth on GaAs. The degree of immiscibility is also discussed using the regular solution approximation.

Electroreflectance and photoluminescence studies of In1−xGaxP1−yAsy lattice-matched to GaAs

Electroreflectance measurements were performed on In1-xGaxP1-yAsy quaternary alloys grown on (100) GaAs by liquid-phase epitaxy in order to determine the precise band gap (E0) and broadening parameter (Γ). It was found that the band gap energies obtained by photoluminescence measurements differ slightly from the precise energy gap determined by ER measurements. The broadening parameters in the ER spectra of In1-xGaxP0.7As0.3 LPE layers inside the miscibility gap of this alloy system are comparable with those of In1-xGaxP0.96As0.04 LPE layers, and hence the LPE growth is less affected by the immiscibility, suggesting that the extraordinarily broadened band-edge luminescence in In1-xGaxP0.7As0.3 is not due to the local distribution of the energy gap caused by the immiscibility. The effects of the immiscibility on the ER spectra are discussed in connection with the LPE growth conditions.

Ureterosigmoidostomy, Conduit and Continent Urinary Diversion

diversion. However, operative techniques are standardized today and the pouchrelated complication rates well known (2.8–4% early complications, 18–36.3% late complications). When a continent diversion cannot be performed, conduit diversion is required. The colonic conduit should be preferred in children and when life expectancy is long. With increasing life ex-pectancy of our patients, careful long-term follow-up (metabolic alterations, vitamins and secondary malignancies) after any type of urinary diversion become increasingly important and should be the subject of investigation.