How medical students define surgical mentors

BACKGROUND: Current literature does not define ideal qualities of surgical mentors. We sought to define mentoring qualities desired by medical students in attending and resident surgeons. METHODS: We conducted a survey asking third-year medical students to identify the best attending surgeon and resident surgeon mentors during their surgical clerkship and to explain their selections. Comments were systematically evaluated using content analysis. RESULTS: The survey response rate was 94.8%. Attending surgeon mentors were described by 84 students; 70 students described resident surgeon mentors. Students most frequently described the "teacher" role for attending surgeons. For resident surgeon mentors, students most often ranked the "person" role. Students prioritized characteristics or attributes within roles differently for attending and resident surgeon mentors. CONCLUSIONS: Medical students' expectations of attending and resident surgeon mentors differ. Emphasis on behaviors consonant with identified characteristics may improve mentoring of medical students by surgeons and increase interest in surgical careers.     

Multicenter Selective Lymphadenectomy Trial‐I confirms the central role of sentinel node biopsy in contemporary melanoma management

Sentinel lymph node (SLN) biopsy has become a standard procedure for many patients with melanoma and is recommended in numerous national and professional melanoma guidelines. The Multicenter Selective Lymphadenectomy Trial (MSLT‐1) confirms earlier large database studies and prospective clinical trials in demonstrating the independent and unequalled prognostic value of the SLN. It also demonstrates the ability of biopsy‐directed management to provide effective regional disease control with the least possible morbidity. These benefits are not in question and provide ample justification for the procedure, even without evidence of a survival benefit. However, MSLT‐1 also provides strong evidence of a substantial reduction in the risk of melanoma death for patients with intermediate thickness melanomas who harbour occult nodal metastases at the time of presentation. Denying appropriately selected patients with melanoma the opportunity to undergo SLN biopsy is no longer reasonable or acceptable.     

Papillary tumor of the pineal region

Primary pineal gland malignancies are uncommon and seldom have papillary architecture. We report a case of a 22‐year‐old male patient who presented with progressive headache, horizontal nystagmus and worsening diplopia. MRI of the brain showed a lesion in the pineal region. The patient was taken for resection of the lesion which was classified as papillary tumor of pineal region (PTPR). Histologically, the neoplasm was cellular, characterized by eosinophilic cells with indistinct borders, large pleomorphic nuclei, numerous apoptotic figures without necrosis or microvascular proliferation. Prominent perivascular pseudorosettes were seen. Diffuse immunoreactivity for cytokeratin 8–18 was noted. Synaptophysin antibody showed membranous and cytoplasmic positivity. Weak staining for GFAP, vimentin, S‐100 protein, and neuron specific enolase (NSE) were observed only focally. This is a case report of this rare pineal region neoplasm which only recently has been described as a histopathologic entity. Although the clinicopathological characteristics of this tumor are not entirely understood, a brief review of the literature as well as our contribution suggest an indolent neoplasm with a tendency for local recurrence. Histologically, PTPR demonstrates a unique assortment of epithelial, ependymal, and neuroendocrine features. The differential diagnosis of papillary neoplasms of the pineal region is reviewed.     

Pulmonary arteriovenous malformations: techniques and long-term outcome of embolotherapy

Over a 10-year period, 276 pulmonary arteriovenous malformations (PAVMs) were occluded with balloon embolotherapy in 76 patients, 67 (88%) of whom had hereditary hemorrhagic telangiectasia. Eleven patients (14%) were discovered by means of family screening with measurement of arterial blood gases and chest radiography. Epistaxis, dyspnea, hemoptysis, and hemothorax occurred in 79%, 71%, 13%, and 9% of patients, respectively. Clinical histories of strokes and transient ischemic attacks were present in 18% and 37% of patients, respectively. Computed tomographic scans of 59 patients showed stroke in 36%. Sixty-five percent of PAVMs were located in the lower lobes, which correlated with the finding of more pronounced hypoxemia in the upright position. After embolotherapy, symptomatic hypoxemia was corrected, and serial values have remained constant for 5 years. Complications were minimal, and no patient required surgery. Balloon embolotherapy is effective long-term therapy for PAVMs, and family screening should be pursued because of the possibility of a higher frequency of paradoxical embolization (stroke) than previously recognized.     

Effectiveness of ECMO for burn-related acute respiratory distress syndrome

Introduction

Acute respiratory distress syndrome (ARDS) is a complication that affects approximately 40% of burn patients and is associated with high mortality rates. Extracorporeal membrane oxygenation (ECMO) therapy is a management option for severe refractory hypoxemic respiratory failure; however, there is little literature reporting the effectiveness of this therapy in burns. Our study objective was to review patient outcomes in burns following severe ARDS treated with ECMO.

Comparison of cytological features of myxopapillary ependymomas on crush preparations

Myxopapillary ependymoma (ME) is a rare neoplasm found predominantly in the sacro‐coccygeal region in adults and is characterized by its distinct epithelial and stromal components. From 1990 to April 2008, a total of 10 ME cases were recorded at our institution. Six out of 10 cases underwent frozen section examination with concomitant crush preparations, which forms the basis of this study. The clinical and cytologic findings in all six cases were reviewed. There were four males and two females. The age ranges from 15 to 36 years with a mean age of 27 years. The epithelial component of ME is strikingly similar for all six cases showing tumor cells appearing singly or in loose clusters, most with papillary branching. There was also presence of indistinct cell boundaries, tapered cytoplasmic prolongations, wispy/fragile cytoplasm, and uniform oval‐to‐fusiform shaped nuclei with an evenly distributed chromatin pattern. The stromal component was composed mainly of thick, metachromatic material and adenoid cystic‐like areas. One case showed rosette‐like structures. These aforementioned characteristics can be utilized to distinguish ME from other primary and metastatic tumors such as meningioma, adenoid cystic carcinoma, chordoma, mucinous adenocarcinoma, chondrosarcoma, and germ cell tumors. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.     

Infrequent p53 mutations in 7,12-dimethylbenz[a]anthracene–induced mammary tumors in BALB/c and p53 hemizygous mice

We conducted experiments to determine if p53 alterations, which are frequent in human breast cancers, were also common in murine mammary tumors. In 13 mammary tumors from 7,12-dimethylbenz[a]anthracene (DMBA)-treated BALB/c mice were immunohistochemically analyzed for overexpression of p53; p53 protein was not detectable. Three of the tumors were established as cell lines in vitro. p53 protein was rarely detected at passage 4 in these lines but was overexpressed by passage 8 in two of them. The p53 nucleotide sequence was shown to be wild type in one primary mammary tumor and in the two p53-overexpressing cell lines. One cell line that overexpressed p53 in vitro was implanted into BALB/c mice. The resulting tumors retained the wild-type p53 nucleotide sequence but no longer expressed detectable levels of p53 protein, suggesting that the overexpression of wild-type p53 was related to in vitro culture conditions. The effect of DMBA on mammary-tumor development was also tested in mice rendered hemizygous for p53. These mice and wild-type littermate controls had no differences in susceptibility to induction of mammary tumors by oral administration of DMBA. Furthermore, Southern blot hybridizations detected no gross alterations in the wild-type p53 allele in mammary tumors from the p53-deficient mice. Point mutation of the wild-type p53 allele was also infrequent in the DMBA-induced mammary tumors from hemizygous p53 mice; it occured in only one of seven tumors. Thus, the p53 gene is apparently not a primary target for genetic alterations in DMBA-induced mammary tumors. Next, we examined mammary tumors derived from D1 and D2 transplantable hyperplastic alveolar nodule (HAN) outgrowths, which rapidly form tumors containing Ha-ras mutations after DMBA treatment. As ras and p53 mutants can cooperate in transformation, we examined whether D1 and D2 HAN outgrowths have p53 mutations. Unlike in the DMBA-induced primary mammary tumors, nuclear p53 accumulation was observed frequently (10 of 14) in tumors that arose from D1 and D2 HAN outgrowths. Direct sequencing of the entire coding region of the p53 cDNA from six D1 and D2 tumors confirmed that the sequence was wild type. Although wild-type p53 was retained in both DMBA-induced mammary tumors and mammary tumors derived from D1 and D2 preneoplastic outgrowths, wild-type p53 overexpression was detected only in D1 and D2 tumors. Therefore, D1 and D2 tumors appear to arise by a pathway in which p53 expression is altered, whereas DMBA induction affects a different pathway that does not require such alteration. © 1994 Wiley-Liss, Inc.     

Hyperbilirubinemia, hypocarbia and periventricular leukomalacia in preterm infants: relationship to cerebral palsy

This study comprised 103 preterm infants with a gestational age less than 33 weeks who were born in Tampere University Hospital and who were followed up to two years of age. Sixty-four perinatal variables were compared to ultrasound findings in the neonatal period and neurologic handicap at the age of two years. Duration of hypocarbia (PCO2 < or = 30 mmHg) during the first 72 h and hyperbilirubinemia (the mean level of serum total bilirubin) at three days of age were independently and significantly related to periventricular leukomalacia, but not directly to cerebral palsy. The only perinatal variables related independently and significantly to cerebral palsy at two years of age were periventricular leukomalacia and ventriculomegaly. According to these results, periventricular leukomalacia was the main predictor of cerebral palsy in preterm infants. In addition to hypocarbia, hyperbilirubinemia may also be involved in the pathogenesis of extensive (severe cystic) periventricular leukomalacia.     

Magnetic resonance angiography findings in the early post-carotid endarterectomy period

This preliminary study was designed to investigate the ability of multiple axial volume three-dimensional fourier transform (3DFT) time-of-flight (TOF) magnetic resonance angiography (MRA) to depict the carotid bifurcation in the early post-carotid endarterectomy period. Five patients underwent intra-operative digital subtraction angiography (DSA) and carotid MRA within 5 days of carotid endarterectomy. An axial volume fast imaging in steady-state precession (FISP) gradient-echo 3DFT TOF carotid MRA technique in this limited series appeared to display accurately the surgically significant abnormalities at the carotid bifurcation after endarterectomy. However, in normal or near-normal intra-operative DSA studies, overestimation of internal carotid artery stenoses was encountered. Postoperative MRA demonstrates potential as a useful non-invasive investigation after carotid endarterectomy but should be interpreted with caution until larger studies become available.