Surgical experience with right atrial-aortic fistula and penetration of the superior vena cava by a protruding Accufix atrial J-shaped retention wire.

A 57-year-old woman who had a dual chamber pacemaker implanted in June 1990 for sick sinus syndrome had developed heart failure since 1993. Although fluoroscopy revealed that the proximal J-shaped retention wire of the lead had fractured and had protruded through the outer insulation in 1994, and also that the distal J-shaped retention wire of the lead had protruded through the outer insulation in 1997, a transthoracic echocardiographic examination diagnosed tricuspid valve regurgitation, suggesting that the right atrial-aortic fistula might have been overlooked. In an attempt to avoid migration of the J-shaped retention wire from the lead and to repair the tricuspid regurgitation, it was decided that an operation be performed; however, intraoperative transesophageal echocardiography showed a right atrial-aortic fistula. Intraoperative inspection also revealed that the right atrial-aortic fistula and penetration of the superior vena cava had been caused by the Accufix atrial J-shaped retention wire. Under total cardiopulmonary bypass and induced cardiac arrest, a right atriotomy was performed and the atrial and ventricular leads were removed from the tips. The atrial orifice of the fistula and the aortic orifice were closed. Finally, a new dual-chamber pacing system with bipolar epicardial pacing leads was implanted. Postoperative inspection revealed that the proximal retention wire had fractured, the tip of the retention wire had protruded through the outer insulation, and the distal J-shaped outer insulation was damaged.     

Dye-guided sentinel lymphadenectomy in clinically node-negative and node-positive breast cancer patients

Background  Sentinel lymphadenectomy has been used to assess the axillary nodal status in patients with breast cancer in an attempt to avoid unnecessary axillary dissection. Most studies have examined the utility of this procedure in clinically node-negative patients. However, the clinical evaluation of axillary nodes is often inaccurate for both clinically node-negative and clinically node-positive patients. Methods  We performed dye-guided sentinel lymphadenectomy in both clinically node-negative and clinically node-positive patients with breast cancer. All patients also underwent a formal axillary dissection. The results of imprint cytology, frozen sections, and permanent sections of the sentinel lymph node (SLN) were compared with each other and with histologic findings of the nonsentinel nodes. Results  The SLN was identified in 30 (79%) of 38 patients with clinically negative nodes, and in 11 (92%) of 12 patients with clinically positive nodes. For clinically node-negative patients, SLN evaluation yielded a diagnostic accuracy of 90%, a sensitivitiy of 72%, and a specificity of 100%. For clinically node-positive patients, these values were 100%, 100% and 100%, respectively. These values were not significantly different for the two groups of patients. Conclusions  Sentinel lymphadenectomy may be useful in assessing the axillary nodal status of both clinically node-positive and clinically node-negative breast cancer patients.     

Visualization of the thymus with therapeutic doses of radioiodine in patients with thyroid cancer

Two cases of papillary carcinoma of the thyroid are presented in which whole-body scans following therapeutic doses of iodine-131 revealed intense anterior mediastinal uptake. In both cases, the mediastinal uptake was absent from scans obtained after removal of the entire thymus. Histologically, the resected thymus glands showed hyperplasia and contained neither thyroid tissue nor metastatic foci of thyroid carcinoma. We therefore concluded that anterior mediastinal uptake of radioiodine may be caused by hyperplasia of the thymus.     

In vitro effects of eicosanoid synthesis inhibitors in the presence of linoleic acid on MDA-MB-231 human breast cancer cells

We investigated the effects of cyclooxygenase and lipoxygenase inhibitors in the presence of linoleic acid (LA), as well as the direct effects of prostaglandin E (PGE) and leukotriene B (LTB) on a human breast cancer cell line (MDA-MB-231)in vitro. Piroxicam, esculetin, and nordihydroguaiaretic acid (NDGA) suppressed cell growth and thymidine incorporation. However, a low concentration (1 µg/ml) of indomethacin (INDO) stimulated cell growth and thymidine incorporation, while a high concentration of INDO (30 µg/ml) inhibited both. Esculetin and NDGA reduced the secretion of LTB, whereas piroxicam reduced the secretion of PGE. INDO reduced the secretion of PGE, but a low concentration of INDO increased the secretion of LTB. Consequently, cell growth was correlated with the PGE and/or LTB concentrations when the cells were treated with these cyclooxygenase or lipoxygenase inhibitors. On the other hand, exogenous PGE₂ partially reversed the inhibition of thymidine incorporation caused by INDO, whereas LTB₄ exerted a similar effect in the case of esculetin or NDGA. The reversibility of the piroxicam effect with PGE₂ is not convincing. Therefore, it is suggested that the growth of MDA-MB-231 cellsin vitro is affected by both the lipoxygenase and cyclooxygenase products, probably the other eicosanoids rather than PGE₂ and LTB₄.     

A case of pheochromocytoma with severe paralytic ileus

We report herein a rare case of a 26 year old woman with pheochromocytoma complicated by paralytic ileus. She presented with remarkable abdominal distension and respiratory difficulty but was effectively treated by surgical removal of the tumor with preoperative and operative management using α and β adrenergic blocking agents. An excessive and persistent catecholamine production from large tumors or massive metastases characterizes this rare complication, and a review of the English and Japanese literature is given following this report.     

Mass screening for cancer of the uterine cervix in Miyagi Prefecture

The number of women screened for cervical cancer in Miyagi Prefecture between January of 1962 and the end of March of 1981 is 1,078,000. The yearly screening rate for women over the age of 30 was 9.5% in 1970, but reached 20.4% in 1980. As the screening rate has increased, the detection rate for cervical cancer has gradually fallen. In 1970 the detection rates for invasive cancer and carcinoma in situ were 0.14 and 0.15%, but in 1980 it was 0.034 and 0.035%, respectively. During this period the truncated standardized prevalence rate for invasive cancer fell from 287.3 per 100,000 in 1970 to 97.1 in 1980; for carcinoma in situ it fell from 198.7 in 1970 to 37.5 in 1980. The truncated standardized incidence rate for invasive cancer alone was 32.9 per 100,000 between 1969 and 1972 and 12.1 between 1973 and 1977. The standardized death rate due to malignant neoplasm of the uterus in Miyagi Prefecture fell from 4.5 per 100,000 in 1970 to 3.4 in 1980.     

Cheiro-oral-pedal syndrome in thalamic infarction

Sensory disturbance around the corner of the mouth, in the palm of the hand and in the foot on the same side (cheiro-oral-pedal syndrome) has been reported only in 2 patients with brainstem lesion. We report 2 cases of cheiro-oral-pedal syndrome; the causative lesion was revealed by magnetic resonance imaging to be in the ventral posterolateral and ventral posteromedial nuclei of the thalamus.     

Accumulation of Abnormally High Ploid Nuclei in the Liver of LEC Rats Developing Spontaneous Hepatitis

Enlarged hepatocytes with huge nuclei were found in LEC rats with hereditary hepatitis. Flow cytometric analysis of the DNA content of nuclei from jaundiced LEC rats revealed the presence of very high polyploids, such as 32n and 64n. At the age of 12 weeks, before the onset of hepatitis, 8n polyploid nuclei were more frequent in LEC rats than in LEA rats, a sibling line of LEC rats. Binucleated hepatocytes were also more frequent in LEC rats than in LEA rats at week 4. Bi-, tri- and tetra-nucleated cells whose nuclei were sometimes different in size were observed when jaundice became manifest. The number of proliferating liver cells, determined by pulse labeling with 5-bromo- 2'-deoxyuridine (BrdU), was higher in LEC rats than in LEA rats at 2, 4, 8, 12 and 14 weeks, with a maximum at week 4. A remarkable increase of BrdU uptake was observed at week 16, when jaundice developed. The possible involvement of abnormal cytokinesis and kariokinesis in the manifestation of hepatitis was suggested.     

DNA damage and altered gene expression of enzymes for metabolism and DNA repair by tamoxifen and toremifene in the female rat liver

Effects of hepatocarcinogenic TAM and non-hepatocarcinogenic TOR on the formation of hepatic DNA adducts and on the gene expression of hepatic drug-metabolizing enzymes and DNA repair enzymes/proteins were comparatively examined in female Sprague-Dawley rats treated with TAM (20 or 40 mg/kg/day, i.g.) or TOR (40 mg/kg/day, i.g.) for 1, 2 or 8 weeks. Hepatic TAM-DNA adducts were formed even after 1 week of treatment with TAM at either dose, and the adduct levels increased in a dose- and treatment period-dependent manner, whereas no DNA adducts were detected in any of the TOR-treated rats. Conversely, TAM and TOR showed almost the same capacity for increasing the gene expression of drug-metabolizing enzymes responsible for metabolic activation and detoxification, at least up to the 2-week treatment mark. Accordingly, differences in DNA adduct formation between TAM- and TOR-treated rats would not be primarily dependent on the capacity for inducing hepatic drug-metabolizing enzymes. In addition, a drastic increase in the gene expression of cytochrome P4503A2 (CYP3A2), an activation enzyme of TAM, by the 8-week treatment with TAM might have contributed to the increased formation of DNA adducts. Gene expressions of DNA repair enzymes/proteins responsible for a nucleotide excision repair system were not significantly changed in any of the rats treated with either drug. The present findings suggest that the difference between TAM and TOR in hepatocarcinogenic potency is dependent on the capacity to form DNA adducts rather than modulating the expression of drug-metabolizing enzymes and DNA repair enzymes/proteins.     

Radiofrequency ablation of small breast cancer followed by surgical resection

BACKGROUND: With the growing demand from patients for less-invasive procedures, the shift from surgical extirpation to ablative local control of breast tumors is an emerging focus in breast cancer care. This study was performed to determine the feasibility and safety of treating small breast cancer with radiofrequency (RF) ablation. METHODS: Patients with biopsy-proven invasive or non-invasive breast cancer underwent RF ablation under general anesthesia. Before RF ablation, all patients were confirmed to have a localized lesion using imaging modalities. Wide excision or total mastectomy with sentinel lymph node biopsy or axillary lymph node dissection was performed. The resected tumor was examined histologically with hematoxylin-eosin (H&E) and nicotinamide adenine dinucleotide-diaphorase (NADH) staining. RESULTS: Ten patients completed the treatment without RF ablation-related complications. The mean tumor size was 1.1 cm (range: 0.5-2.0 cm). Histological evaluation of the ablated tissue using H&E staining revealed a spectrum of changes ranging from complete coagulation necrosis of tumor cells to normal-appearing tumor cells. However, NADH-diaphorase showed no staining of viable tumor cells in the RF-ablated region in all of the patients. CONCLUSIONS: RF ablation is promising as a minimally invasive ablation technique in the local treatment of invasive or non-invasive breast cancer. However, further study is necessary before RF ablation can replace conventional breast conservation therapy for patients with small breast cancer.