Measurement of beam-axis displacement from the isocenter during three-dimensional conformal radiosurgery with a micro-multileaf collimator

We describe the displacement of the beam-axis from the planning isocenter in clinical situations during three-dimensional conformal radiosurgery using an Acculeaf bi-directional micro-multileaf collimator. The displacements were recorded for 64 ports using a video imaging system and a stereotactic arc. The mean displacement was 0.41+/-0.25 mm.

Induction of chromatin damage and distribution of isochromatid breaks in human fibroblast cells exposed to heavy ions

The frequency of chromatid breaks and the distribution of isochromatid breaks were measured in G2-phase normal human fibroblasts prematurely condensed a short time after exposure to low- or high-LET radiations. The average number of isochromatid breaks from a single particle traversal increased with increasing LET values, while the average number of chromatid-type breaks appeared to reach a plateau. The distribution of isochromatid breaks after high-LET iron particles exposure was overdispersed compared to gamma-rays, indicating that a single iron particle traversal through a cell nucleus can produce multiple isochromatid breaks.

Intra-arterial CT-angiography for cerebral arteriovenous malformation--initial experiences for treatment planning of radiosurgery

PURPOSE

To clarify the feasibility and effectiveness of intra-arterial CT angiography (IACTA) for treatment planning of arteriovenous malformation radiosurgery.

METHODS AND MATERIALS

A CT scanner installed in an angiographic examination room was used. Helical IACTA was performed in 22 patients during continuous intra-arterial infusion of contrast medium via the internal carotid or vertebral artery, and dynamic IACTA was performed in 20 of these patients with reconstruction at 0.2-s intervals. The dynamic IACTA was repeated for each 3- or 5-mm increment to encompass the nidus. Subtractions were performed in postembolization cases. A retrospective review of IACTA was performed to assess the effectiveness of dynamic scans.

RESULTS

No complications related to the angiographic procedure or CT imaging were detected. High contrast enhancement was obtained for both helical and dynamic IACTA. In 18 of the 20 cases (90%), draining veins were separated from the nidus by using the enhancement patterns, and in 13 cases (65%), feeding arteries were separated.

CONCLUSION

Dynamic IACTA added important information for target-volume determinations. Conventional CT and MRI could be omitted from the protocol, and the period that patients wore the frame was substantially shortened. We conclude that IACTA is a practical and useful method for radiosurgical treatment planning of arteriovenous malformations.

Adjuvant pelvic irradiation in patients with pathologic T2b carcinoma of the uterine cervix

Patients with cervical cancer are subject to postoperative adjuvant therapy if the histopathologic examination reveals parametrial involvement. This study evaluated the patterns of failure in patients with pathologic parametrial invasion (pT2b) treated with adjuvant pelvic irradiation. Between April 1985 and March 1997, 45 patients with pT2b cervical cancer were treated with postoperative pelvic irradiation. The median age was 52 years. Preoperative clinical stages were stage Ib in 8 patients, IIa in 4, and IIb in 33. Twenty-three patients had lymph node metastasis. The median total dose of whole pelvic radiation therapy was 50 Gy. Occurrence of pelvic failure or distant metastasis according to the nodal status was examined. None of the 22 patients without lymph node metastasis developed distant metastasis. Among the 23 node-positive patients, 6 developed distant metastasis as an initial failure site. The 5-year overall survival of the entire group was 78%. The actuarial distant metastasis-free rates at 5 years were 73% and 100% for those with and without pelvic lymph node metastasis, respectively (P = 0.016). Results support previous evidence for chemoradiation in patients with pelvic lymph node metastasis. However, it appears that the role of systemic chemotherapy for node-negative pT2b patients is yet to be established.

Adjuvant pelvic irradiation in patients with node-negative carcinoma of the uterine cervix

BACKGROUND

To assess the role of post-operative pelvic radiotherapy in cervical cancer patients without lymph node metastases.

MATERIALS AND METHODS

The records of 61 patients with cervical cancer treated with radical hysterectomy and bilateral pelvic lymphadenectomy followed by pelvic irradiation were reviewed. The distribution of FIGO stage was IB in 34, II4 in 5 and IIB in 22. The patients were treated with 10-18 MV X-rays using a fractional daily dose of 1.8-2.0 Gy to a median total dose of 50 Gy.

RESULTS

The actuarial 5-year pelvic control rate was 95%. There was no isolated pelvic lymph node recurrence. The overall 5-year survival of the entire group was 89%. The mean age of the patients who developed recurrence was lower than the other patients (46 years vs. 53 years, p=0.07).

CONCLUSION

The results indicated that post-operative pelvic irradiation was effective in preventing pelvic recurrence in patients with node-negative cervical cancer.

Death from hypovolemic shock caused by perforation of duodenal ulcer in a patient with angiosarcoma of the scalp

We report a case of an 86-year-old woman with angiosarcoma on the scalp, who died from hypovolemic shock caused by perforation of a duodenal ulcer. A purple-red macule was first noticed on her left temporal scalp, and over a 1-month period this macule rapidly grew to a 6 cm purple-red indurated plaque with hematomas. The diagnosis of angiosarcoma was made based on the clinical features and histopathological finding of the lesional skin. Perilesional injections of recombinant interleukin 2 (rIL-2) were followed by surgical resection of the lesion and graft repair. However, 5 months later, new hematomas appeared and increased in number and size to cover her cheek, left temporal scalp and around the grafted area. Electron-beam radiotherapy showed only a temporary effect and the skin lesions with spontaneous severe bleeding extended rapidly again toward a wide region of the left half of the scalp and cheek. The patient died of hypovolemic shock after acute abdominal pain with intestinal hemorrhage. The surgical pathology revealed the presence of a perforated duodenal ulcer which might have been the direct cause of hypovolemic shock.

A case of intramedullary spinal cord tumor producing human chorionic gonadotropin

We experienced a case of a persistent trophoblastic disease associated with gradually progressive Brown-Sequard syndrome, which was found to be due to a primary intramedullary spinal cord germinoma with syncytiotrophoblastic giant cells (STGC). We performed both chemotherapy and radiotherapy on separate occasions. Although the chemotherapy appeared to be ineffective, radiotherapy resulted in the disappearance of spinal cord lesions for four years. We reported a case of intramedullary spinal cord germinoma with STGC for which radiotherapy was a better therapeutic modality.

Clinical role of Tc-99m-MIBI scintigraphy in non-Hodgkin's lymphoma

This study was designed to investigate the relationship between Tc-99m-hexakis-2-methoxyisobutylisonitrile (MIBI) scintigraphy and outcome of treatment in patients with non-Hodgkin's lymphoma (NHL). Forty-five patients with NHL were studied with Tc-99m-MIBI before any treatment. Images of the lesions were obtained at 20 min and 2 h after radionuclide administration. Visual semi-quantitative interpretation was performed for Tc-99m-MIBI (grade 0-4) scintigraphy. Patients underwent 3-5 cycles of CHOP chemotherapy with/without involved field radiotherapy for large tumors. Their responses to treatment were evaluated at the end of chemotherapy and during the follow-up period. Forty of 45 patients (89%) showed abnormal uptake of Tc-99m-MIBI. There was no correlation between intensity of MIBI accumulation and response to chemotherapy. However, patients with negative or decreased MIBI activity 2 h after radionuclide administration showed worse response to chemotherapy compared to those with continued MIBI activity. MIBI activity could not predict the development of relapse in the follow-up study. In this study, the number of patients was small and we could not reach definite conclusions. However, we think that MIBI scintigraphy is not valuable for predicting the chemotherapy outcome in patients with NHL.

FR901469, a novel antifungal antibiotic from an unidentified fungus No. 11243. III. Structure determination

A novel antifungal antibiotic, FR901469, was isolated from an unidentified fungus No. 11243. It is a water-soluble 40-membered macrocyclic lipopeptidolactone, consisting of D-Ala, L-Tyr, L-Val, trans-4OH-L-Pro, trans-3OH-L-Pro, threo-3OH-L-Gln, Gly, L-Orn, L-Thr, three residues of D-alloThr and a (3R)-hydroxypalmitic acid. Its structure, including absolute configurations, was unequivocally determined as 1 based on chemical and spectroscopic evidence.

Breast-conserving therapy for ductal carcinoma in situ

This retrospective analysis evaluates the treatment results and prognostic factors of 114 patients with ductal carcinoma in situ (DCIS) undergoing breast conserving therapy (BCT) at Keio University Hospital Department of Radiology, between 1988 and 1997. A total of 132 patients with DCIS of the breast came to our hospital between 1988 and 1997, and 114 cases were suitable candidates for BCT. All of the patients were female and ranged in age from 26 to 81 years (median 46). Ninety-one patients were premenopausal, and 23 were postmenopausal. Median clinical tumor size was 2.0 cm (0-8.0 cm). Postoperatively 48 cases received 50 Gy/25 fractions of external irradiation to the whole breast via tangential ports. The follow-up period after treatment ranged from 11 to 162 months (median 46.7). The local relapse-free rate and overall survival rate of the 114 patients were 89.5% and 100%, respectively. Local failure and regional nodal failure occurred in 12 and 1 patient, respectively. Radiotherapy was a significant risk factor for local failure (p=0.05). No postmenopausal patients developed local failure, but the difference did not reach statistical significance (p=0.103). The 12 recurrent cases underwent additional surgery and all remain alive without recurrence, to date, i.e., at least 16 months. Breast-conserving surgery plus irradiation is appropriate treatment for DCIS patients.

Effect of administration with the extract of Gymnema sylvestre R. Br leaves on lipid metabolism in rats

Extract of Gymnema sylvestre R. Br leaves (GE) was orally administered once a day to rats fed a high fat diet or normal fat diet for 3 weeks to investigate its influence on lipid metabolism. As a result, GE did not influence body weight gain or feed intake in both diet groups during the experimental period. The apparent fat digestibility was significantly decreased by GE in both diet groups for the last 2 weeks of the experimental period, though not the apparent protein digestibility. In addition, the excretion of neutral sterols and acid steroids into feces was increased by GE in both diet groups. Furthermore, GE decreased the total cholesterol and triglyceride levels in serum. On the other hand, blood lecithin-cholesterol acyltransferase (LCAT) activity was increased by GE. Moreover, it was suggested that GE influenced cecal fermentation and that propionic acid and acetic acid contents in cecum were significantly increased by GE. Consequently, it was suggested that GE improved serum cholesterol and triglyceride levels through influence over a wide range of lipid metabolism in rats.

Effect of long term-administration with Gymnema sylvestre R. BR on plasma and liver lipid in rats

Extract of Gymnema sylvestre leaves was administered to rats receiving either a high fat diet or normal fat diet for 10 weeks to investigate its influence on plasma and liver lipids and on visceral fat accumulation. In addition, its effect was compared with those of chitosan and the influence of combined use of these two substances was also evaluated. Within the high fat diet groups, the extract suppressed body weight gain and accumulation of liver lipids to the same extent as chitosan and the combined use. In addition, intraperitoneal fat and fat drop vacuoles on the epithelium of renal tubules, noted in the high fat diet group, were scattered by administration of the extract with the same results as for chitosan and combined use. Within the normal fat diet groups, plasma triglyceride levels decreased by administration of the extract, with similar results as chitosan and combined use. Concerning plasma total cholesterol, there was no decreasing effects with the extract, as found with chitosan and combined use. However, the effect of chitosan on plasma total cholesterol tended to be enhanced when used in combination with the extract. In addition, long-term administration of the extract did not show any influence on hematological and blood chemical parameters.

Cell killing and mutation induction by heavy ion beams

Carbon beam radiotherapy for cancer patients was initiated in Japan in June 1994. This study attempts to clarify the radiobiological effects of heavy ion beams. In this study, human cancer cell lines (RMG-1, MDA-MB231) and V79 cells were used. The cell killing was determined by colony forming assay, and mutation induction was determined by counting the number of 6-thioguanine resistant colonies (hprt locus mutation assay). The cell lines were irradiated with carbon (20 or 80 keV/microm) or neon beams (80 keV/microm). Carbon ions with a higher LET value (80 keV/microm) had an enhanced cytotoxic effect compared to those with a lower LET value (20 keV/microm). Carbon beams produced a slightly stronger cytotoxic effect than neon beams when irradiated at the same LET level (80 keV/microm), but the difference was not remarkable. The mutant fraction was significantly higher in all cell lines when they were irradiated with heavy ion beams, compared to the results for X-ray irradiation. The mutant fraction increased when the LET of the carbon beams increased. At equivalent LET values, the mutant fraction was lower for neon beams than for carbon beams. Fractionation of carbon beam irradiation had no effect on survival, but reduced the mutant fraction. Neon beams might be more appropriate for heavy ion therapy, especially when higher doses are being used. In addition, the fractionation of heavy ion beam administration might be appropriate for reducing the mutant fraction.

Indications of stereotactic irradiation for brain lesions

Stereotactic radiosurgery (SRS: single-fraction stereotactic irradiation) was originally developed to treat benign lesions in the brain, and has been adopted for the treatment of small primary or metastatic brain tumours. It has recently been recommended that stereotactic radiotherapy (SRT: fractionated stereotactic irradiation) be applied to the treatment of brain tumours; however, it requires much more time and work than SRS, and sufficient radiobiological evaluations of these techniques have never been carried out. Biologically effective doses were calculated to determine the indications for SRS and SRT, and to decide on an effective SRT schedule, incorporating the factors of 'repair' and 'cell proliferation'. The results suggest that SRS would be recommended for arteriovenous malformations and benign tumours that have distinct margins separating them from surrounding normal tissue and SRT would be recommended for benign or malignant brain tumours without clearly defined boundaries. The recommended SRT schedules would be 7 Gy x 7 fractions every other day for malignant tumours and 3.5 Gy x 12 fractions every other day for benign tumours. However, clinically, these schedules should be modified according to many other factors in individual cases.

Microspinosamide, a new HIV-inhibitory cyclic depsipeptide from the marine sponge Sidonops microspinosa

Microspinosamide (1), a new cyclic depsipeptide incorporating 13 amino acid residues, was isolated from extracts of an Indonesian collection of the marine sponge Sidonops microspinosa. Its structure was elucidated by extensive NMR and mass spectral analyses, and by chemical degradation and derivatization studies. The tridecapeptide 1 incorporates numerous uncommon amino acids, and it is the first naturally occurring peptide to contain a beta-hydroxy-p-bromophenylalanine residue. Microspinosamide (1) inhibited the cytopathic effect of HIV-1 infection in an XTT-based in vitro assay with an EC(50) value of approximately 0.2 microg/mL.

Effect of combined treatment with radiation and low dose etoposide on cell survival

BACKGROUND

To improve the radiotherapy results, we evaluated etoposide as an effective radiosensitizer by using cultured cell-lines.

MATERIALS AND METHODS

Four cell lines having different doubling times (DT) were used: V79 (Chinese hamster fibroblasts, DT = 9 hours), (1), T24 (human bladder cancer, DT = 19 hours) (2), MDA-MB231 (human breast cancer, DT = 25-30 hours) (3) and RMG1 (human ovarian cancer, DT = 50 hours) (4). Cell survival was determined by colony assay and cell cycle analysis was performed by flow-cytometry.

RESULTS

The survival curves showed RMG1 to be the most radiosensitive, followed by MDA-MB231, T24, and V79. V79 was most chemosensitive to etoposide, followed by T24, MDA-MB231 and RMG1. Neither 24-hours exposure to etoposide (< or = 0.05 microgram/ml) or 0.5-h exposure (< or = 1.0 microgram/ml) had any cell killing effect on any of the cell lines used. When the cells were irradiated after exposure to 1 microgram/ml of etoposide for 0.5 hours, no radiosensitization was observed in any of the cell lines except V79. Enhanced radiosensitivity was observed in V79 and T24 cells (which have a relatively short DT) when they were incubated with 0.05 microgram/ml etoposide for 24 hours but no enhanced effect was seen in MDA-MB231 or RMG1 cells (which have a relatively long DT).

CONCLUSION

It is suggested that a combination of radiation and etoposide may be useful in the treatment of rapidly growing cancer.

Corydendramines A and B, defensive natural products of the marine hydroid Corydendrium parasiticum

Two novel piperidinol metabolites, corydendramines A (1) and B (2), have been isolated from the marine hydroid Corydendrium parasiticum. The structures of these compounds, which deter feeding by a potential hydroid predator, were determined by interpretation of their spectral data.

Postoperative radiation therapy for pituitary adenoma

BACKGROUND

We evaluated the efficacy of postoperative radiation therapy (RT), prognostic factors for local control probability, dose response relationship and treatment sequelae in 75 patients with pituitary adenoma.

MATERIALS AND METHODS

A total dose of 48-60 Gy (median: 50 Gy) was delivered with a conventional fractionation schedule after surgery. Of 75 patients, 55 (73%) were followed for more than 5 years and 27 (36%) were followed for more than 10 years with a median of 95 months.

RESULTS

Five- and 10-year local control probabilities were 87.1% and 85.0%, respectively. Univariate analysis revealed that age (p = 0.007), tumor volume smaller than 30 cm3 (p = 0.018) and the absence of prolactin secretion (p = 0.003) were significantly favorable prognostic factors for local control probability. After multivariate analysis combining these 3 factors, tumor volume smaller than 30 cm3 (p = 0.017) and age (p = 0.039) were statistically significant. Patients with prolactinoma greater than 30 cm3 showed particularly poor local control rates. No significant improvement of the local control rate was detected with increasing total irradiation doses between 48 and 60 Gy (p = 0.29). The most common side effect was hypopituitarism, and there were no severe sequelae such as optic neuropathy or brain necrosis.

CONCLUSION

Except with prolactinoma, the dose of postoperative RT for pituitary adenoma should not exceed 50 Gy. Large prolactinoma, however, was very difficult to control with the irradiation doses between 50 and 60 Gy, and would be good candidates for stereotactic radiosurgery or stereotactic radiation therapy.

Postoperative radiation therapy for stage IB-IIB carcinoma of the cervix with poor prognostic factors

BACKGROUND

To investigate failure pattern and to evaluate the prognostic impact of lymph node metastasis in patients with cervical cancer treated with postoperative adjuvant pelvic irradiation.

MATERIALS AND METHODS

Ninety-eight patients with FIGO IB to IIB cervical cancer were treated with radical hysterectomy, bilateral pelvic lymphadenectomy and postoperative radiation therapy. All the patients had at least one of the following pathologic risk factors for pelvic recurrence; 1) positive margins, 2) positive pelvic lymph nodes other than common iliac node, 3) deep stromal invasion more than 50% or parametrial invasion.

RESULTS

The 5-year overall survival (OAS) rate for the entire patient group was 82%. Causes of the first failure were pelvic recurrence in 5 cases and distant metastasis in 15 cases. Fifteen of the 47 patients with positive pelvic lymph nodes developed distant metastasis, whereas distant metastasis was noted in only 1 of 51 patients without lymph node metastasis. The 5-year OAS rates for patients with and without pelvic lymph node metastasis were 76% and 89%, respectively (p = 0.018).

CONCLUSION

Despite receiving postoperative pelvic irradiation, apparently lower survival was observed for node positive patients.

The modified tangential irradiation technique for breast cancer: how to cover the entire axillary region

PURPOSE

The two-portal tangential irradiation technique has usually been applied to breast cancer patients after breast-conserving surgery (1, 2) and is expected to irradiate the axillary lymph node region to some extent (3). We investigated the range of the axillary region covered by this technique and tried to devise an optimal irradiation technique (modified tangential irradiation) that would cover the axillary lymph node region properly.

METHODS AND MATERIALS

We checked the status of the surgical clips left at axillary lymph node sites by reviewing the simulator films and planning CT scans of 63 patients who underwent axillary dissection of level I, I-II, or I-III lymph nodes. Then we created the modified tangential irradiation technique and applied this technique to 16 patients and checked the irradiation volume by CT scans.

RESULTS

We found that all of the surgical clips on lateral-view simulator films were on the ventral side of the dorsal edge line of the humeral head. All but one clip were on the caudal side of the caudal edge line of the humeral head. Accordingly, it is possible to irradiate almost all axillary lymph node regions by setting the dorsal edge of the irradiation field on lateral-view simulator films at the dorsal edge of the humeral head and the cranial edge at the caudal edge of the humeral head.

CONCLUSIONS

All breast tissue and the entire axillary lymph node region can be covered by the modified tangential irradiation technique without increasing the lung volume irradiated.

Structures of five components of the actinomycin Z complex from Streptomyces fradiae, two of which contain 4-chlorothreonine

Structure elucidation of five components of the actinomycin Z complex (Z(1)-Z(5)) isolated from Streptomyces fradiae is described. The components were separated by Si gel column chromatography and TLC/PLC and analyzed by ESIMS, FABMS, LC-MS of derivatized hydrolysates, and 2D NMR techniques. This permitted determination of the complete structures of actinomycins Z(1)-Z(5). In Z(3) and Z(5,) site 1 of the beta-depsipeptide is occupied by the rare 4-chloro-L-threonine, an amino acid not previously found in an actinomycin. The structural variants of the actinomycin Z complex have the molecular architecture typical of other actinomycins but possess greater structural diversity resulting from the presence of several highly unusual amino acids. Actinomycins Z(3) and Z(5,) but not Z(1), were more potent than actinomycin D in cytotoxicity assays against three tumor cell lines.

Radiotherapy for large hepatocellular carcinoma combined with transcatheter arterial embolization and percutaneous ethanol injection therapy

This study was performed to determine the effect of radiotherapy (RT) combined with transcatheter arterial embolization (TAE) and percutaneous ethanol injection (PEI) on large HCC. Between 1988 and 1996, 102 patients with unresectable, biopsy proven HCC underwent uniform pretreatment assessment followed by TAE and PEI. Of the 102 patients, 68 (67%) had more than 2 lesions in the liver, and the largest tumor sizes in each patient ranged from 3 to 8 cm in diameter. Immediately after TAE and PEI, external beam RT (36 to 70 Gy) was administered to the largest tumors only in 44 patients. The cause-specific 5-year survival rate for all patients was 39.9%. The 3-year survival rate of the RT group was better than that of the no RT group (81.1% vs. 54.6%). The cumulative local control rates of the largest treated tumors were 53.2% in the RT group and 32.7% in the no RT, respectively (p=0.006). When the survival rate was compared between patients with and without local control in the RT group, that of patients with local control was significantly better than that with local recurrences (p=0.048). No deaths or major treatment related complications occurred. RT combined with TAE and PEI did not clearly show improvement of the survival, however, it effectively controlled large HCC, and demonstrated minimal toxicity. This treatment may represent therapeutic option for some patients with unresectable large HCC.