A Rare Case of Anterior Chest Wall Schwannoma Masquerading as a Breast Tumor

A schwannoma is a tumor that develops on peripheral nerves or spinal roots. Although any part of the body can be affected, the breast is a quite unusual site for schwannomas. We report herein a case of schwannoma presenting as a breast tumor. In the current case, the tumor showed both clinically and mammographically as a well-defined breast mass. Of interest, sonographically, the well-defined mass appeared to be located in subcutaneous tissue, not in breast parenchyma, and this finding was confirmed histopathologically. These findings indicate the possibility that a schwannoma arising from subcutaneous breast tissue can show exophytic growth to the breast and appear as a breast tumor. In other words, our case implies the possible presence of a “pseudo” breast schwannoma.Key words: Schwannoma, Breast, Breast cancerA schwannoma is a relatively rare neoplasm that occurs from Schwann cells of the peripheral nerve sheath.^1–3 Although schwannomas may occur in any organ, a breast schwannoma is extremely rare and accounts only 2.6% of schwannomas.^1–4 We report herein a case of schwannoma suspected to be a breast tumor. The concern with breast schwannoma is a differential diagnosis, since on mammogram it sometimes resembles a breast cancer or tumor.     

Endoscopy-assisted transoral resection of a parapharyngeal space schwannoma without mandibular dissection

Of the schwannomas that arise from the parapharyngeal space, those in the high cervical region are particularly invasive, requiring mandibular dissection. Because these tumors are benign, however, excessive surgical invasion and postoperative neurological complications should be avoided. Postoperative dropout symptoms may be avoided by intracapsular extraction, including nerve integrity monitoring (NIM) and narrow-band imaging (NBI). Video laryngoscopy surgery is reported to be useful for transoral resection of pharyngeal and laryngeal tumors. This report describes the transoral removal of a giant schwannoma located in the high cervical region from a 74-years-old man using a surgical support device without mandibular dissection.The tumor was located on the right lateral pharyngeal wall and extended from the upper oropharynx to the hypopharynx while compressing the epiglottis to the skull base. No separation was observed between the internal jugular vein and the internal carotid artery. The tumor was diagnosed as a schwannoma with no malignancy on the basis of the histology of a core needle biopsy (CNB), and was completely and safely removed endoscopically using NIM and NBI, with no need for an external incision or mandibular dissection. This case illustrates that even a huge sympathetic schwannoma located in the parapharyngeal space at a high cervical position can be excised transorally using video-laryngoscopic surgery (TOVS) without mandibular dissection.     

Impact of aging on the clinical outcomes of Japanese patients with coronary artery disease after percutaneous coronary intervention

Japan has become an aging society, resulting in an increased prevalence of coronary artery disease. However, clinical outcomes of elderly Japanese patients after percutaneous coronary intervention (PCI) remain unclear. Of the 15,227 patients in the Shinken Database, a single-hospital-based cohort of new patients, 1,214 patients who underwent PCI, was evaluated to determine the differences in clinical outcomes between the elderly (≥75 years) (n = 260) and the non-elderly (<75 years) (n = 954) patients. A major adverse cardiac event (MACE) was defined as a composite end point, including all-cause death, myocardial infarction (MI), and target lesion revascularization. Male gender and obesity were less common, and the estimated glomerular filtration rate (eGFR) was significantly lower in the elderly than in the non-elderly. Left ventricular ejection fraction (LVEF) was comparable between these groups. Left main trunk disease and multivessel disease were more common in the elderly than in the non-elderly group. Occurrence of MACE was frequent, and the incidences of all-cause death, cardiac death, and the admission rate for heart failure were significantly higher in the elderly patients. Multivariate analysis showed that prior MI, low eGFR, and poor LVEF were independent predictors for all-cause death in the elderly patients. Elderly patients had worse clinical outcomes than the non-elderly patients. Low eGFR and LVEF were independent predictors of all-cause death after PCI, suggesting that left ventricular dysfunction and renal dysfunction might synergistically contribute to the adverse clinical outcomes of the elderly patients undergoing PCI.     

High linear-energy-transfer radiation can overcome radioresistance of glioma stem-like cells to low linear-energy-transfer radiation

Ionizing radiation is applied as the standard treatment for glioblastoma multiforme (GBM). However, radiotherapy remains merely palliative, not curative, because of the existence of glioma stem cells (GSCs), which are regarded as highly radioresistant to low linear-energy-transfer (LET) photons. Here we analyzed whether or not high-LET particles can overcome the radioresistance of GSCs. Glioma stem-like cells (GSLCs) were induced from the GBM cell line A172 in stem cell culture medium. The phenotypes of GSLCs and wild-type cells were confirmed using stem cell markers. These cells were irradiated with ⁶⁰Co gamma rays or reactor neutron beams. Under neutron-beam irradiation, high-LET proton particles can be produced through elastic scattering or nitrogen capture reaction. Radiosensitivity was assessed by a colony-forming assay, and the DNA double-strand breaks (DSBs) were assessed by a histone gamma-H2AX focus detection assay. In stem cell culture medium, GSLCs could form neurosphere-like cells and express neural stem cell markers (Sox2 and Musashi) abundantly in comparison with their parental cells. GSLCs were significantly more radioresistant to gamma rays than their parental cells, but neutron beams overcame this resistance. There were significantly fewer gamma-H2AX foci in the A172 GSLCs 24 h after irradiation with gamma rays than in their parental cultured cells, while there was no apparent difference following neutron-beam irradiation. High-LET radiation can overcome the radioresistance of GSLCs by producing unrepairable DNA DSBs. High-LET radiation therapy might have the potential to overcome GBM''s resistance to X-rays in a clinical setting.     

Glucocorticoid receptor and serum‐ and glucocorticoid‐induced kinase‐1 in esophageal adenocarcinoma and adjacent Barrett's esophagus

Barrett's esophagus (BE) is a consequence of gastroesophageal reflux disease and is predisposed to esophageal adenocarcinoma (EAC). EAC is an exemplar model of inflammation‐associated cancer. Glucocorticoids suppress inflammation through glucocorticoid receptor (GR) and serum‐ and glucocorticoid‐induced kinase‐1 (Sgk1) expressions. Therefore, we immunolocalized GR and Sgk1 in EAC and the adjacent BE tissues and studied their association with clinical disease course in 87 patients with EAC who underwent surgical resection (N = 58) or endoscopic submucosal dissection (N = 29). Low GR and Sgk1 expressions in adjacent BE tissues were associated with adverse clinical outcomes (P = 0.0008 and 0.034, respectively). Patients with low Sgk1 expression in EAC cells exhibited worse overall survival (P = 0.0018). In multivariate Cox regression analysis, low GR expression in the adjacent nonmalignant BE tissues was significantly associated with worse overall survival (P = 0.023). The present study indicated that evaluation of GR and Sgk1 expressions in both the EAC cells and adjacent nonmalignant BE tissues could help to predict clinical outcomes following endoscopic and surgical treatments. In particular, the GR status in BE tissues adjacent to EAC was an independent prognostic factor.     

Benefits of robotically-assisted surgery for complex mitral valve repair

OBJECTIVESTo determine whether robotic mitral valve repair can be applied to more complex lesions compared with minimally invasive direct mitral valve repair through a right thoracotomy. Open in a separate windowMETHODSWe enrolled 335 patients over a 9-year period; 95% of the robotic surgeries were performed after experience performing direct mitral valve repair.RESULTSThe mean age in the robotic versus thoracotomy repair groups was 61 ± 14 vs 55 ± 11 years, respectively (P < 0.001); 97% vs 100% of the patients, respectively, had degenerative aetiologies. Repair complexity was simple in 106 (63%) vs 140 (84%), complex in 34 (20%) vs 20 (12%) and most complex in 29 (17%) vs 6 (4%) patients undergoing robotic versus thoracotomy repair, respectively. The average complexity score with robotic repair was significantly higher versus thoracotomy repair (P < 0.001). The robotic group underwent more chordal replacement using polytetrafluoroethylene and less resections. All patients underwent ring annuloplasty. Cross-clamp time did not differ between the groups, and no strokes or deaths occurred. More patients undergoing robotic repair underwent concomitant procedures versus the thoracotomy group (30% vs 14%, respectively; P < 0.001). The overall repair rate was 100%, with no early mortality or strokes in either group. Postoperative mean residual mitral regurgitation was 0.3 in both groups, and the mean pressure gradient through the mitral valve was 2.4 vs 2.7 mmHg (robotic versus thoracotomy repair, respectively; P = 0.031).CONCLUSIONSRobotic surgery can be applied to repair more complex mitral lesions, with excellent early outcomes.     

Enzymatic properties of dipeptidyl aminopeptidase IV produced by the periodontal pathogen Porphyromonas gingivalis and its participation in virulence

Porphyromonas gingivalis is a major pathogen associated with adult periodontitis. We cloned and sequenced the gene (dpp) coding for dipeptidyl aminopeptidase IV (DPPIV) from P. gingivalis W83, based on the amino acid sequences of peptide fragments derived from purified DPPIV. An Escherichia coli strain overproducing P. gingivalis DPPIV was constructed. The enzymatic properties of recombinant DPPIV purified from the overproducer were similar to those of DPPIV isolated from P. gingivalis. The three amino acid residues Ser, Asp, and His, which are thought to form a catalytic triad in the C-terminal catalytic domain of eukaryotic DPPIV, are conserved in P. gingivalis DPPIV. When each of the corresponding residues of the enzyme was substituted with Ala by site-directed mutagenesis, DPPIV activity significantly decreased, suggesting that these three residues of P. gingivalis DPPIV are involved in the catalytic reaction. DPPIV-deficient mutants of P. gingivalis were constructed and subjected to animal experiments. Mice injected with the wild-type strain developed abscesses to a greater extent and died more frequently than those challenged with mutant strains. Mice injected with the mutants exhibited faster recovery from the infection, as assessed by weight gain and the rate of lesion healing. This decreased virulence of mutants compared with the parent strain suggests that DPPIV is a potential virulence factor of P. gingivalis and may play important roles in the pathogenesis of adult periodontitis induced by the organism.     

A quinol peroxidase inhibitor prevents secretion of a leukotoxin from Aggregatibacter actinomycetemcomitans

Takashima E, Yamada H, Yajima A, Shiomi K, ōmura S, Kiyoshi K. A quinol peroxidase inhibitor prevents secretion of a leukotoxin from Aggregatibacter actinomycetemcomitans. J Periodont Res 2009; doi: 10.1111/j.1600‐0765.2009.01211.x. © 2009 John Wiley & Sons A/S Background and Objective: Quinol peroxidase (QPO) catalyzes peroxidase activity using quinol in the respiratory chain as a substrate. Quinol peroxidase is essential for the secretion of leukotoxin (LtxA), which destroys leukocytes and erythrocytes in humans and is one of the major virulence factors of Aggregatibacter actinomycetemcomitans, which is associated with localized aggressive periodontitis. In the present study, we aimed to find a highly potent QPO inhibitor to attenuate the virulence of A. actinomycetemcomitans. Material and Methods: For screening of QPO inhibitors, QPO activity was measured kinetically by SpectraMax Plus with 96‐well UV plates. Three hundred compounds in the Kitasato Institute for Life Sciences Chemical Library were screened. Secretion of LtxA in the culture supernatant was examined by sodium dodecyl sulfate–polyacrylamide gel electrophoresis. Cytotoxicity against human promyelocytic leukemia cell line (HL‐60) cells from the culture supernatant was measured by Trypan Blue exclusion test. Results: The present study characterized ascofuranone as a highly potent inhibitor of QPO (K_i = 9.557 ± 0.865 nm ). Ascofuranone inhibited secretion of LtxA by A. actinomycetemcomitans in a dose‐dependent manner, making A. actinomycetemcomitans less pathogenic to HL‐60 cells. Conclusion: Quinol peroxidase inhibitors are promising candidates as alternative drugs for the treatment and prevention of the onset of localized aggressive periodontitis. Using ascofuranone as a seed compound, further study of QPO inhibitors could provide novel chemotherapeutic strategies for controlling localized aggressive periodontitis.     

Therapeutic results using high-dose-rate intracavitary irradiation in cases of cervical cancer

A comparison of the 5-year relative survival rates has been made between cases of cancer of the uterine cervix treated with 226Ra low-dose-rate intracavitary irradiation and those treated with 60Co high-dose-rate intracavitary irradiation (using the remote afterloading system, RALS). External irradiation using LINAC was also administered in both groups. The 5-year relative survival rates of the low-dose-rate cases were 82.6, 55.4, 49.0, and 18.2% in stage I, II, III, and IV cases, respectively, whereas they were 97.4, 55.1, 56.8, and 29.0% in the respective high-dose-rate cases. The differences between the two groups were not statistically significant. Delayed radiation complications of the rectum were frequent in both groups (approximately 14%) and those of the urinary bladder were somewhat less frequent (approximately 8%). The incidence of such complications did not differ significantly between the two groups.