Application of conditional probability analysis to distant metastases from lung cancer.

The aim of this study was to reveal whether there was non-randomness in the occurrence of metastasis and, if the non-randomness was denied, whether there were specific metastatic patterns in lung cancer patients. Patients who presented with pathologically diagnosed lung cancer between January 1986 and March 2009 at our hospitals were included. A statistical method and conditional probability analysis were used to analyze the data. Under the condition of one metastatic organ A (lung, bone, brain, liver or adrenal gland; the 5 most common metastatic organs), we determined the conditional probability of distant metastasis to a specific organ B, which was written as P(B | A), and compared it with the probability of distant metastasis P(B). The study group consisted of 1,994 patients. Of the 1,994 patients, 839 (42.1%) had distant metastases at the time of the initial diagnosis of lung cancer. With the exception of the comparisons between P(lung) and P(lung | adrenal gland) and between P(adrenal gland) and P(adrenal gland | lung), there were statistically significant differences between P(B | A) and P(B) in the 5 metastatic organs. In addition, P(B | A) and P(C | B | A) varied according to each organ and P(confined to A), P(confined to A and B) and P(confined to A, B and C) were different in each metastatic organ. In lung cancer patients, distant metastasis occurred non-randomly and there may be certain specific patterns of distant metastasis. The accumulation of knowledge of specific patterns of metastasis may aid the approach to individualized treatments.

Infected subdural haematoma due to Salmonella enterica serovar Typhimurium in an adult.

A 65-year-old man with a history of alcoholism and gastrectomy was diagnosed with an infected subdural haematoma due to Salmonella enterica serovar Typhimurium. He was successfully treated with surgical drainage and intravenous ceftriaxone. To our knowledge, there has been no detailed case report in English of infected subdural haematoma or subdural empyema due to Salmonella Typhimurium in adults.

Neuregulin receptor ErbB2 localization at T-tubule in cardiac and skeletal muscle.

Previous studies have indicated that ErbB receptors for neuregulins play an important role in cardiac development and muscle spindle formation during embryogenesis; however, little is known about their functions in adulthood. Recent reports indicate that breast cancer therapy with humanized monoclonal ErbB2 antibody induces cardiomyopathy, suggesting that ErbB2 serves as a crucial signaling receptor, even in the adult heart. Here, we examine ErbB2 expression and localization in both cardiac and skeletal muscle of adult mice via immunoblot and immunohistochemistry. ErbB2 was detected as a band approximately 185 kD molecular mass in each cardiac and skeletal muscle extraction. Confocal images of double labeling showed that ErbB2 was colocalized with caveolin-3 in cardiac muscle and with dihydropyridine receptor in skeletal muscle, suggesting that ErbB2 was localized at the T-tubule. In addition, immunoelectron micrographs clearly demonstrated that ErbB2 was located at the T-tubule in both types of muscle. Taken together, the results of the present study suggest that neuregulin-ErbB2 signaling plays a role in the physiological function of cardiac and skeletal muscle, even in adulthood.

[Diaphragm pacing with a spinal cord stimulator].

BACKGROUND: Diaphragm pacing with electrical stimulation of the phrenic nerve is an established treatment for central hypoventilation syndrome. The device, however, is not readily available in Japan. For pain control, we applied the spinal cord stimulator to bring about phrenic nerve stimulation. The purpose of this study is to evaluate the efficacy and feasibility of phrenic pacing using the compromise method. METHOD AND PATIENTS: We implanted a spinal cord stimulator in five patients with chronic central hypoventilation. The stimulation electrode was placed along the phrenic nerve in the neck, and the device was implanted in the anterior chest. We used the cyclic mode, and set the parameters at 1 second ramp up, 2 second on, 3 second off. The pulse width and the frequency were set at 150 mu sec and 21 Hz respectively. The amplitude was adjusted to obtain sufficient tidal volume and to maintain PaCO2 at around 40 mmHg. RESULT: During the follow-up period from 3 to 34 months (mean 23), stable and sufficient ventilation was observed in all patients without complications. CONCLUSION: Though longer follow-up is necessary, diaphragm pacing with the spinal cord stimulator is feasible as a treatment for central hypoventilation syndrome.

Phrenic nerve stimulation for diaphragm pacing with a spinal cord stimulator: technical note.

BACKGROUND: Diaphragm pacing with electrical stimulation of the phrenic nerve is an established treatment for central hypoventilation syndrome. The device, however, is not readily available, at least in Japan. We used the spinal cord stimulator for pain control for phrenic nerve stimulation. The purpose of this study is to evaluate the efficacy and feasibility of phrenic pacing with the compromise method. METHODS: We implanted a stimulator for spinal cord stimulation (Itrel 3 or X-trel, Medtronic, MN) in 4 patients with chronic hypoventilation because of brainstem dysfunction of various origins. The stimulation electrode was placed along the right phrenic nerve in the neck, and the device was implanted in the anterior chest. We used the cyclic mode, and set the parameters at 1 second ramp up, 2 seconds on, 3 seconds off. The pulse width and the frequency were set at 150 microsec and 21 Hz, respectively. The amplitude of the output was adjusted to obtain sufficient tidal volume and to maintain PaCO(2) at around 40 mm Hg. RESULTS: During the follow-up period from 6 to 19 months (mean 8.3 months), stable and sufficient ventilation were observed in all patients without complications. One patient with sleep apnea syndrome used the device only at night and became free from a respirator. Three patients who were completely respirator-dependent became ambulatory during the daytime. CONCLUSION: Though longer follow-up is necessary, diaphragm pacing by stimulation of the phrenic nerve with the spinal cord stimulator is feasible for a treatment of central hypoventilation syndrome.

Extreme night bradycardia developing after malfunction of a lumboperitoneal shunt.

CASE REPORT: An 8-year-old boy who was treated for hydrocephalus with lumboperitoneal shunting presented with extreme night bradycardia. RESULTS AND CONCLUSION: The night bradycardia disappeared after shunt revision, suggesting that the probable cause was secondary to long-lasting increased intracranial pressure (ICP). Long-lasting increased ICP is known to be associated with papilledema, but it has rarely been reported to induce night bradycardia in clinical practice. Extreme night bradycardia in this setting is not only a clinical sign of increased ICP but also a possible cause of cardiogenic sudden death, which must be borne in mind in the management of patients with shunted hydrocephalus.

Schwannoma arising from the tentorium at an unusual location: case report.

OBJECTIVE AND IMPORTANCE: We present a case of schwannoma attached to the tentorium. CLINICAL PRESENTATION: A 41-year-old woman without evidence of neurofibromatosis presented with a 3-month history of headache, positional vertigo, and truncal ataxia. Magnetic resonance imaging revealed an extra-axial cystic mass lesion in the left anteromedial cerebellar region with a dural tail sign. INTERVENTION: The tumor was removed completely by retrosigmoid craniotomy. Dense adhesion of the tumor to the inferior surface of the tentorium was confirmed during surgery. On light microscopic study, this neoplasm was composed of spindle cells and showed palisaded structures. Immunohistochemically, the tumor cells stained positive for S-100 protein and vimentin. Reticulin staining revealed a pericellular pattern of distribution of reticulin fibers. Electron microscopy confirmed the presence of a basement membrane encompassing the tumor cells. From these findings, the tumor was diagnosed as a schwannoma arising from the tentorium. CONCLUSION: To our knowledge, this case report is the first to describe a schwannoma arising from the tentorium. Our case report indicates that schwannoma is a possible pathology in the differential diagnosis of dura-based tumors.