Chemotherapy in the treatment of advanced or recurrent olfactory neuroblastoma

Background: Olfactory neuroblastoma is a rare sino‐nasal tumor arising from the olfactory epithelium and is often characterized by local invasion or metastasis. The role of chemotherapy in the treatment of this tumor is unclear. The purpose of this study was to review our institution’s experience of chemotherapy for advanced or recurrent olfactory neuroblastoma. Methods: Twenty‐one patients with histologically proven olfactory neuroblastoma were treated at our institution between 1992 and 2002. Twelve of these patients received chemotherapy in the setting of unresectable or recurrent disease and were retrospectively reviewed for clinical characteristics, treatment outcome or survival. Results: Eight patients of the 12 patients received cisplatin‐based chemotherapy and the remaining four patients received chemotherapy consisting of docetaxel plus irinotecan (three patients) or cyclophosphamide, doxorubicin, and vincristine (1 patient). A partial response was achieved in five patients, with an overall response rate of 42%, although the chemotherapeutic regimens were heterogeneous. Two partial responses were obtained among the three patients who received docetaxel plus irinotecan. The response rate to chemotherapy was 83% in the younger age group (<40 years), as opposed to 0% in the older age group (≥40 years), and the difference between the two groups was statistically significant (P = 0.02). Conclusion: Our study indicated that olfactory neuroblastoma would be sensitive to chemotherapy, especially with young patients. Docetaxel plus irinotecan has the possibility of showing favorable response, and warrants further investigation.     

IMPROVED BALLOON‐TIPPED TRANS‐ANAL ILEUS TUBE

Background: For management of bowel obstruction due to colorectal cancer, endoscopic trans‐anal decompression technique has been first reported by Lelcuk et al. in 1986 using balloon dilatation technique. Since then, various types of trans‐anal decompression tubes have been clinically used for patients suffering from left side obstructing colorectal cancer as an emergent decompressing device. At present, two types of trans‐anal ileus tube (trans‐anal decompression tube) have been available for clinical use, but they have two main problems that are late colon perforations caused by the tip of the tube and tube obstruction by stool. Methods: Analysis on three late colon perforations experienced with the use of conventional devices drew possible improvements to make a trans‐anal ileus tube less harmful. To overcome the pitfalls inherent to conventional tubes, the author has developed an improved trans‐anal ileus tube with a balloon installed at the very end of the tube (‘balloon‐tipped type’) made of silicone, measuring 1200 or 1700 mm in total length and 22 Fr in outer diameter. It has been used for 12 cases with obstructing colorectal cancer etc. and its outcomes were compared with those obtained by the use of conventional trans‐anal ileus tube. Results: No late perforations have been encountered, but tube obstruction did occur in one of 12 cases. Conclusion: The new trans‐anal ileus tube with a balloon installed at the tip of ileus tube is considered to be safer and especially effective in preventing late colon perforation and tube obstruction.     

Does substance P act as a pain transmitter?

Pain signals appear to be transmitted by a variety of chemicals. Masanori Otsuka and Mitsuhiko Yanagisawa review evidence that substance P, present in 10–20% of primary afferent fibers, is one such transmitter. In the isolated CNS preparations of the newborn rat the tachykinin antagonist spantide reversibly depresses nociceptive C-fiber reflexes of slow-time course without affecting the monosynaptic reflex. These observations together with other lines of evidence suggest that SP serves as a transmitter in a subpopulation of primary afferent C-fibers and produces slow excitatory postsynaptic potentials in second-order neurons in the dorsal horn to transmit delayed pain signals to the CNS.     

RELAXATION OF MESENTERIC ARTERY OF STROKE PRONE SPONTANEOUSLY HYPERTENSIVE RATS BY CALCIUM REMOVAL

1. The time courses of the relaxation, induced by removal of extracellular Ca2+, of K-depolarized mesenteric artery preparations from stroke prone spontaneously hypertensive rats (SHRSP) and Wistar-Kyoto rats (WKY) were compared. 2. The time course of the decline in extracellular Ca2+ was estimated from the time course of the relaxation and the concentration-response curve of K(+)-depolarized preparations to Ca2+. The time course of the decline in the intracellular free Ca2+ concentration was also estimated from the reported relation between Ca2+ concentration and the contraction of skinned vascular smooth muscle. 3. The time course of relaxation was exponential, the curve being made up of three components. The time course was slower in preparations from SHRSP, especially the first component of the relaxation curve. 4. The time courses of the decline in the intracellular and extracellular Ca2+ concentrations were also exponential, being made up of three components and were also slower in the preparation made from SHRSP. 5. The wall and muscle layer of the mesenteric arteries used in the present experiments were significantly thicker in the SHRSP preparations. 6. Calculation of the half relaxation time, based on the diffusion of Ca2+ across the blood vessel wall, suggested that the slower relaxation in preparations from SHRSP is due largely to the thicker muscle layer, although differences in Ca2+ sequestration by the smooth muscle cells may also be involved.     

Comparison of histopathological characteristics of allograft biopsy between responder and non-responder to antiproteinuric effect of angiotensin-converting enzyme inhibitor (ACEI)

Abstract:  Angiotensin-converting enzyme inhibitor (ACEI) has become recognized as agents that have renoprotective effects in the treatment of progressive renal diseases including post-transplant kidneys. Previously we demonstrated the safety and effectiveness of ACEI treatment on the hypertensive proteinuric post-transplant patients ( N  = 10) who had been followed up for 12 months. However, not all patients show good response in urinary protein reduction. We aimed to analyse the histopathological factor(s) affecting the responsiveness of proteinuria to ACEI treatment. Fourteen post-transplant patients with proteinuria who were treated with ACEI and underwent allograft biopsy were analysed. Eight patients showed 50% or more reduction in proteinuria (responder). The other 6 patients showed less (< 50%) reduction in proteinuria (non-responder). There was no difference in clinical characteristics (BP, renal function, donor age, recipient body mass index), dietary sodium or protein intake, and diuretic use between the two groups. As a histopathological characteristic, glomerular size in responder group was significantly larger than that in non-responder group. This suggests that the large glomerular size at least partly contributes to the responsiveness in urinary protein reduction to ACEI treatment in kidney allograft recipients with proteinuria.     

Surgical treatment of descending thoracic aortic aneurysm under temporary bypass with antithrombogenic tube and bio-medicus centrifugal pump

Four patients with descending thoracic aortic aneurysm were successfully operated on under temporary bypass with an antithrombogenic tube and a Bio-Medicus centrifugal pump. The bypass flow ranged from 1.0 to 2.4 l/min with the mean femoral artery pressure of 50 to 70 mmHg. No complications such as paraplegia, hepatic dysfunction or renal failure were encountered in all the patients. Temporary increment of the serum amylase level occurred in all the patients, but any apparent clinical symptoms were not present. The temporary bypass method with an antithrombogenic tube and a centrifugal pump is useful and reliable for surgical treatment of descending thoracic aortic aneurysm.