Treatment of superficial esophageal cancer by external radiation therapy alone: results of a multi-institutional experience.

PURPOSE: To assess the effectiveness and toxicity of external radiation therapy for superficial esophageal cancer. METHODS AND MATERIALS: During the period from March 1979 to November 1996, 78 patients with superficial esophageal cancer received radiation therapy without intracavitary irradiation at nine radiotherapy institutions in Japan. All patients had histologically-proven squamous cell carcinoma. Endoscopic ultrasonography was performed in 34 patients to discriminate mucosal from submucosal cancer. Most of the patients had received radiation therapy using conventional fractionation at an average dose of 65.5 Gy. RESULTS: The survival rates at 1, 2, and 5 years were 88%, 73%, and 45%, respectively. The local control rates at 1, 2, and 5 years were 85%, 79%, and 66%, respectively. Although the difference was not significant, the survival rate of cancer patients with a tumor invading the submucosa was lower than that of the other patients. In 6 mucosal cancer patients, local recurrence was observed in 1 patient with extensive cancer. Regional lymph node recurrence and distant failure were not observed in mucosal cancer patients, while in 28 submucosal cancer patients, the 5-year survival rate and relapse free rate were only 49% and 43%, respectively. Univariate and multivariate analysis identified age as the only significant prognostic factor. Severe late injury, such as esophageal ulcer, perforation, and bleeding, was not observed. CONCLUSION: External radiation therapy is effective for mucosal cancer. However, further investigation is needed to establish a better standard treatment protocol for submucosal cancer.

A new anti-MRSA antibiotic complex, WAP-8294A. I. Taxonomy, isolation and biological activities.

WAP-8294A, produced by Lysobacter sp., is a complex consisting of water soluble depsipeptide antibiotics. It was further purified by column chromatographies and HPLC, and 19 components were obtained. WAP-8294A2, a major component, and minor components A1, A4, Ax8, Ax9 and Ax13 were active against gram-positive bacteria, in particular, methicillin-resistant Staphylococcus aureus (MRSA) in vitro. WAP-8294A2 was highly active in vivo in mice against the systemic infection of MRSA.

[Clinical evaluation of intra-arterial infusion chemotherapy for advanced or recurrent cervical cancer with or without radiotherapy].

We analyzed 52 cases of advanced or recurrent cancer of the cervix treated by intra-arterial infusion chemotherapy (IAIC) with or without radiotherapy. IAIC regimen was separated into two groups: Group I consisted of 5-FU + MMC +/- ADR (30 cases) and group II of CDDP + MMC +/- 5-FU (22 cases). The tip of the catheter was placed in the bifurcation of abdominal aorta or the bilateral internal iliac arteries (7 cases). The overall response rate (CR + PR) was 71%, 87% in patients given radiotherapy, 50% in those without radiotherapy, and 100% in primary cases. The five-year survival rate was 20% in primary cases, 14% in recurrent cases, 3% in Group I and 38% in Group II (p = 0.00182) by chemotherapy regimen. Severe (more than grade III) hematological acute side effect was 48% for all cases, but recovered by interruption of drugs. In 7 cases in which the tip of the catheter was placed in internal iliac arteries, there were severe skin ulcers in 2 cases and severe pain of leg or gluteal region requiring narcotics in 2 cases. These data suggest that IAIC mainly with cisplatin with or without radiotherapy is one of the effective treatments for advanced or recurrent cervix cancer. But we should check the blood flow distribution periodically, and control the concentration of drugs.

[Clinical evaluation of intra-arterial infusion chemotherapy for advanced or recurrent pelvic tumors with or without radiotherapy].

We analyzed 97 cases of various advanced or recurrent pelvic tumors which were cervix, rectal, ovarian and other tumors treated by intra-arterial infusion chemotherapy (IAIC) with or without radiotherapy. The IAIC regimen was separated into two groups: group I consisting of 5-FU + MMC +/- ADR (54 cases) and group II consisting of CDDP + MMC +/- 5-FU (43 cases) from 1985. The catheter was placed in the bifurcation of abdominal aorta, and from 1990, the catheters were placed in bilateral internal iliac arteries (8 cases). The overall response rate (CR + PR) was 65%, 74% in patients receiving radiotherapy, and 47% in those without radiotherapy. There were no significant differences between each primary site and presence of radiotherapy combination in survival rate. Two-year survival rate and 5-year survival rate was 32% and 15% for all cases, and 65% and 33% for CR cases, respectively. A significantly better survival rate was obtained in patients with CR. Five-year survival rate was 4% in group I, and 35% in group II (p = 0.00216) by chemotherapy regimen. Severe (more than grade III) hematological acute side effects were 45% for all cases. In 8 cases in which the catheters were placed in internal iliac arteries, there were severe skin ulcers in 2 cases, and severe pain of leg or gluteal region requiring narcotics in 3 cases. These data suggest that IAIC mainly with cisplatin with or without radiotherapy is one of the effective treatment for advanced or recurrent pelvic tumors. Also, we should check blood flow distribution periodically, and control the concentration of drugs.

Peak effect and dynamic melting of vortex matter in NbSe2 crystals.

We present a mode locking (ML) phenomenon of vortex matter observed around the peak effect regime of 2H-NbSe2 pure single crystals. The ML features allow us not only to trace how the shear rigidity of driven vortices persists on approaching the second critical field, but also to demonstrate a dynamic melting transition of driven vortices at a given velocity. We observe the velocity dependent melting signatures in the peak effect regime, which reveal a crossover between the disorder-induced transition at small velocity and the thermally induced transition at large velocity. This uncovers the relationship between the peak effect and the thermal melting.

Dynamic melting of confined vortex matter.

We study dynamic melting of confined vortex matter moving in disordered, mesoscopic channels by mode-locking experiments. The dynamic melting transition, characterized by a collapse of the mode-locking effect, strongly depends on the frequency, i.e., on the average velocity of the vortices. The associated dynamic ordering velocity diverges upon approaching the equilibrium melting line T(m,e)(B) as v(c) approximately (T(m,e)-T)(-1). The data provide the first direct evidence for velocity dependent melting and show that the phenomenon also takes place in a system under disordered confinement.

Mode locking of vortex matter driven through mesoscopic channels.

We investigated the driven dynamics of vortices confined to mesoscopic flow channels by means of a dc-rf interference technique. The observed mode-locking steps in the IV curves provide detailed information on how both the number of vortex rows and the lattice structure in each flow channel change with magnetic field. Minima in flow stress occur when an integer number of rows is moving coherently, while maxima appear when the incoherent motion of mixed n and n+/-1 row configurations is predominant. Simulations show that the enhanced pinning at mismatch originates from quasistatic fault zones with misoriented edge dislocations induced by disorder in the channel edges.