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Gritz ER, Carr CR, Rapkin D, Abemayor E, Chang LJ, Wong WK, Belin TR, Calcaterra T, Robbins KT, Chonkich G. Predictors of long-term smoking cessation in head and neck cancer patients. Cancer Epidemiol Biomarkers Prev 1993; 2:261-70. [PMID: 8318879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Cigarette smoking is a major risk factor for head and neck cancer, and individuals who continue to smoke past diagnosis and treatment are at elevated risk for further disease. In a randomized controlled trial, a state of the art provider-delivered smoking cessation intervention was compared to a usual care advice control condition. The intervention consisted of surgeon- or dentist-delivered advice to stop smoking, a contracted quit date, tailored written materials, and booster advice sessions. Subjects were 186 patients with newly diagnosed first primary squamous cell carcinomas of the upper aerodigestive tract who had smoked cigarettes within the past year. At randomization, 88.2% of subjects were current smokers. At 12-month follow-up, 70.2% of subjects completing the trial (n = 114) were continuous abstainers; among baseline smokers alone the continuous abstinence (CA) rate was 64.6%. The cotinine validation rate at 12 months was 89.6%. Modeling techniques were utilized in order to derive expected CA rates, which included noncompleter subjects (n = 72). The CA rate expected at 1 year for the entire patient population was 64.2%, and for smokers alone the expected CA rate was 59.4%. Logistic regression analysis carried out on baseline smokers identified predictors of 12-month CA status. These included medical treatment, stage of change, age, nicotine dependence, and race. The intervention effect was not significant, although the sign of the effect was positive. Based on these findings, we recommend systematic brief advice to stop smoking for head and neck cancer patients, with a stepped care approach for patients less able to quit.
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Abstract
In large part, malignancy is the end result of aberrant cell growth and differentiation. Control of these processes is anticipated to result in a suppression of oncogenicity. Retinoic acid (RA), a derivative of vitamin A, has been shown to inhibit proliferation, induce cell differentiation and reverse the malignant phenotype of a variety of tumor cell types. In order to further characterize the antitumor potential of RA, this study examined the in vitro and in vivo effects of this retinoid on cell lines derived from human neuroblastoma (NB). The in vitro phase of this study tested the ability of various compounds to raise intracellular cyclic adenosine 3':5'-monophosphate (cAMP) levels and either alone or in combination with RA, to promote differentiation of two relatively RA-resistant cell lines. Direct activation of the synthetic enzyme adenylate cyclase by forskolin or cholera toxin increased intracellular cAMP levels over 10-fold after 1 hour of treatment, declining over the next 16 to 24 hours. After 5 days of continuous growth in the presence of these agents, cAMP levels remained elevated 2- to 7-fold above control values and were accompanied by a decrease in cell proliferation and an increase in cell differentiation. All these effects were exaggerated in the presence of phosphodiesterase inhibitors. Isoproterenol and epinephrine did not alter cAMP levels and had no discernible biological effects. RA promoted differentiation with little effect on cAMP levels. Combination treatment of cells with RA plus agents that raised cAMP levels resulted in greater degrees of differentiation than seen with single-agent treatment. From these data, it was concluded that: 1. the cAMP synthetic and degradative pathways are functional in the NB cell lines studied; 2. elevation of cAMP is a sufficient but not necessary condition for inhibiting proliferation and promoting differentiation in these cells; 3. elevation of intracellular cAMP potentiates the differentiation-inducing activity of RA; and 4. overcoming retinoid resistance in some tumor cell lines may be feasible by alterations in the cAMP system. This would be of particular value in treating tumors that have lost retinoid responsiveness. The in vivo phase of this study examined the effects of single-agent treatment using RA on the development and growth in nude mice of tumors derived from a NB cell line.(ABSTRACT TRUNCATED AT 400 WORDS)
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Abstract
PURPOSE Tricholemmal cysts, sometimes termed pilomatrixomas, are benign skin neoplasms. This study was undertaken to evaluate the clinical experience with management of pilomatrixomas at a large, referral-based university hospital. PATIENTS AND METHODS The records of patients treated at the UCLA Medical Center were reviewed retrospectively. Patients treated during the years 1966 to 1991 inclusive were reviewed for details of the clinical course. All pathology slides were confirmed histologically. RESULTS Pilomatrixoma was confirmed in 53 patients. Of these, 29 patients (55%) had pilomatrixoma isolated to the head and neck region. All were treated with surgical excision. One patient (3%) experienced recurrence due to inadequate initial excision. Subsequent re-excision resulted in a cure. CONCLUSION Tricholemmal cysts present as solitary, painless, slow-growing cutaneous nodules often resulting in discoloration of the overlying skin. Simple excision cures this benign neoplasm, and recurrences are rare. Fine-needle aspiration biopsy may aid in the diagnostic workup.
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155
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Bailet JW, Mark RJ, Abemayor E, Lee SP, Tran LM, Juillard G, Ward PH. Nasopharyngeal carcinoma: treatment results with primary radiation therapy. Laryngoscope 1992; 102:965-72. [PMID: 1518360 DOI: 10.1288/00005537-199209000-00002] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
One hundred three patients with nasopharyngeal carcinoma were treated with radiotherapy at UCLA Medical Center from January 1955 to December 1990. Overall survival, disease-free survival, and local control rates were analyzed. In addition, survival from 1955 to 1978 and from 1979 to 1990 were evaluated. Overall 5- and 10-year actuarial survival rates for all patients were 58% and 47%, respectively. Disease-free survival rates at 3 and 5 years were 45% and 30%, respectively. Local, persistent, or recurrent disease in the nasopharynx was the primary cause of failure, occurring in 32% of patients and correlating with the initial tumor size (T stage). Twenty-four percent of patients developed distant metastases, which correlated with nodal status but not with T stage. Seventy-nine percent of patients failed either locally or distally by 4 years. Sex, race, age, and T and N stage categories were evaluated as prognostic variables in terms of survival. Control of primary disease is important in determining long-term outcome. Modern imaging techniques have greatly assisted in the evaluation of disease extent and treatment options.
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Abstract
Silvadene cream and Sulfamylon make up the treatment regimen for one contributor (Dr. Crumley). No systemic antibiotics would be given. Any areas of obvious third-degree burns would be debrided and grafted. The tympanic membrane perforation would be treated with antibiotic/steroid drops. The second author concurs with use of Silvadene cream and would avoid any pressure on the area (Dr. Abemayor). While he agrees that systemic antibiotics should be avoided, he also would not prescribe ear drops. He recommends evaluation for a pulmonary or ophthalmologic injury. There is a disagreement regarding imaging studies. One expert would order a CT scan to rule out facial fractures (Dr. Crumley). His counterpart would not order a CT but would check a baseline chest x-ray if there were any sign of pulmonary compromise (Dr. Abemayor). Both experts would obtain an audiogram after the acute problems are treated. In the case of foul drainage, burn reconstruction would be delayed. In addition to treating the otorrhea with ear drops, one physician would add oral antibiotics (Dr. Abemayor). The other author believes tympanoplasty should be performed prior to reconstruction (Dr. Crumley). There were several procedures suggested for the reconstruction. Both authors discuss a method of creating a postauricular pocket, burying the ear pedicle, and using costal cartilage for an inlay helical graft. Another approach involves minimal debridement of the cartilage and letting the wound mature for 6 to 8 months. At that time the area would be debrided and the postauricular skin used for external coverage (Dr. Crumley). If the facial scar is a cosmetic problem 1 year after the injury, triamcinolone injections and local massage should be considered.(ABSTRACT TRUNCATED AT 250 WORDS)
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157
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Bailet JW, Abemayor E, Jabour BA, Hawkins RA, Ho C, Ward PH. Positron emission tomography: a new, precise imaging modality for detection of primary head and neck tumors and assessment of cervical adenopathy. Laryngoscope 1992; 102:281-8. [PMID: 1545657 DOI: 10.1288/00005537-199203000-00010] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Positron emission tomography (PET) has been shown to be effective in detecting intracranial malignancies based on cerebral glucose metabolism. To evaluate the ability of PET to detect extracranial head and neck neoplasms and cervical metastases, 16 patients with primary squamous cell carcinomas were examined. All patients received preoperative computerized tomography (CT) and magnetic resonance imaging (MRI) scans and underwent PET evaluation using intravenous 18F-2-fluoro-2-deoxy-D-glucose (FDG). Histopathologic analysis compared tumor invasion and positive lymph nodes with findings on MRI, CT, and PET images. All primary tumors were delineated by PET, while MRI and CT failed to detect one superficial tumor involving the anterior tongue. Ten nodes were detected by CT and MRI versus 12 nodes demonstrated by PET. PET is highly effective in detecting head and neck carcinomas as well as metastatic cervical lymph nodes. In addition, PET may be useful in evaluating postsurgery and postradiotherapy patients for recurrent and new primary tumors.
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158
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Bailet JW, Abemayor E, Andrews JC, Rowland JP, Fu YS, Dawson DE. Malignant nerve sheath tumors of the head and neck: a combined experience from two university hospitals. Laryngoscope 1991; 101:1044-9. [PMID: 1921630 DOI: 10.1288/00005537-199110000-00003] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Malignant schwannoma is an aggressive neoplasm whose cell of origin and histologic characteristics remain controversial. Despite advances in diagnostic techniques, the natural history of this tumor remains uncertain. The charts of all patients with malignant schwannoma who were treated at the UCLA Center for the Health Sciences and the University of Iowa Hospital and Clinics were retrospectively reviewed. Sixteen patients received surgery and radiotherapy in combination or as sole therapy. Irrespective of treatment modality, prognosis was poor with an overall survival of 15%. Recent advances in imaging and histologic techniques that assist in establishing the diagnosis and delineating tumor location are discussed. In addition, the literature pertaining to malignant schwannoma of the head and neck is reviewed.
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159
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Bates ES, Abemayor E. Slide presentation graphics using a personal computer. A comparative evaluation of available software. ARCHIVES OF OTOLARYNGOLOGY--HEAD & NECK SURGERY 1991; 117:26-30. [PMID: 1716921 DOI: 10.1001/archotol.1991.01870210098020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Most of the available methods for preparing professional slides to be used in oral presentations can be cumbersome, time-consuming, and expensive. Creating high-quality 35-mm slides may require the use of expensive medical illustrators and photographic equipment not available to all physicians. More recently, technology has emerged that permits professional in-office generation of quality slides using commercially available computer graphics software and film recorders. Such a system is simple to establish and maintain when compared with commercial slide production facilities. We will review the hardware requirements of such a system, as well as the advantages and disadvantages of several commercially available software packages. Using a personal computer-based slide-making system, any physician communicating with small or large groups of people can now produce professional-looking slides easily, rapidly, and inexpensively.
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160
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Abemayor E. Intraoperative I-125 seed implantation for extensive recurrent head and neck carcinomas. Am J Otolaryngol 1991. [DOI: 10.1016/0196-0709(91)90126-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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161
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Lando M, Abemayor E, Mendoza V. Pathologic quiz case 1. Nodular fasciitis of the parotid gland. ARCHIVES OF OTOLARYNGOLOGY--HEAD & NECK SURGERY 1991; 117:336-8. [PMID: 1998576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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162
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Abemayor E, Chang B, Sidell N. Effects of retinoic acid on the in vivo growth of human neuroblastoma cells. Cancer Lett 1990; 55:1-5. [PMID: 2245404 DOI: 10.1016/0304-3835(90)90057-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We have investigated the effects of retinoic acid (RA) on the development and growth in nude mice of tumors derived from the human neuroblastoma cell line LA-N-5. When cells were treated with 4 x 10(-6) M RA in vitro there was a marked reduction in the number of mice developing tumors when compared to solvent-treated controls. In vivo treatment with RA reduced tumor formation when the retinoid was given for 5 days before tumor injection and continued for 14 days thereafter. In established tumors, RA inhibited progressive tumor growth. There was no demonstrable effect of RA in vivo on the morphologic phenotype of the tumor cells when these regimens were used. We conclude that oral retinoid administration may prove useful in inhibiting or arresting the growth of neuroblastoma, particularly when there is a small initial tumor burden.
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163
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Ator GA, Abemayor E, Lufkin RB, Hanafee WN, Ward PH. Evaluation of mandibular tumor invasion with magnetic resonance imaging. ARCHIVES OF OTOLARYNGOLOGY--HEAD & NECK SURGERY 1990; 116:454-9. [PMID: 2317328 DOI: 10.1001/archotol.1990.01870040076017] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Evaluating the extent of tumor invasion of the mandible is clinically important in the management of mandibular tumors. Conventional imaging studies including panoramic radiography, bone scans, and computed tomography, as well as clinical evaluation can be unreliable in defining the extent of neoplastic marrow invasion. This study presents the initial UCLA, Los Angeles, Calif, experience with magnetic resonance imaging in evaluating mandibular invasion by benign and malignant neoplasms. Magnetic resonance imaging, using T1 and T2 images, was compared with conventional imaging methods in 11 patients with malignant lesions and nine patients with benign lesions. In all cases, magnetic resonance imaging most accurately determined the full extent of tumor invasion in the mandibular marrow spaces. Magnetic resonance imaging appears to be superior to offer clear benefits over conventional imaging methods, including computed tomography, for the evaluation of tumor invasion of the mandible.
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164
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Lando M, Abemayor E, Verity MA, Sidell N. Modulation of intracellular cyclic adenosine monophosphate levels and the differentiation response of human neuroblastoma cells. Cancer Res 1990; 50:722-7. [PMID: 2153444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We have tested the ability of various compounds to raise intracellular cyclic AMP (cAMP) levels and, either alone or in combination with retinoic acid (RA), to promote differentiation of two "RA-resistant" sublines of LA-N-5 human neuroblastoma cells, designated LA-N-5HP and LA-N-5R9. Direct activation of adenylate cyclase by forskolin and cholera toxin increased intracellular cAMP levels over 10-fold in both cell lines after 1 h of treatment, after which the levels slowly declined for the next 16 to 24 h. After 5 days of continuous treatment, cAMP levels still remained 2- to 7-fold elevated above controls and were accompanied by a decrease in cell proliferation and an increase in neurite outgrowth. All these effects were exaggerated when the agents were combined with phosphodiesterase enzyme inhibitors. Increasing cAMP levels (up to 24-fold) with N6,O2'-dibutyryl cyclic AMP (dbcAMP) or 8-bromo-cAMP also resulted in decreased proliferation and an increase in morphological differentiation. Isoproterenol and epinephrine did not alter cAMP levels and had no discernible biological effects. Of the agents that raised cAMP levels, only dbcAMP caused an increase in acetylcholinesterase activity. This effect was duplicated with sodium butyrate and prostaglandin E1 in the absence of an increase in cAMP. RA promoted differentiation but also had little effect on cAMP levels. Combination treatment of cells with RA plus agents that raised cAMP levels resulted in greater degrees of differentiation than seen with single agent treatments. We conclude that: (a) the cAMP synthetic and degradative pathways are functional in LA-N-5HP and LA-N-5R9 cells; (b) elevation of cAMP is sufficient for inhibiting proliferation and promoting neurite outgrowth from these cells, but is not a necessary condition for inducing differentiation; and (c) elevation of intracellular cAMP potentiates the differentiation-inducing activity of RA.
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165
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Strasnick B, Moore DM, Abemayor E, Juillard G, Fu YS. Occult primary tumors. The management of isolated submandibular lymph node metastases. ARCHIVES OF OTOLARYNGOLOGY--HEAD & NECK SURGERY 1990; 116:173-6. [PMID: 2297408 DOI: 10.1001/archotol.1990.01870020049013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The management of patients with cervical metastases from unknown primary tumors presents a therapeutic challenge to both the head and neck surgeon and radiotherapist. If after careful search the primary tumor remains truly occult, traditional methods of radiotherapy encompassing fields from the base of skull to clavicles are often employed, with significant attendant morbidity. To determine if more limited therapy would be effective in cases of isolated regional lymph node metastases, the patterns of tumor spread to nodes in the submandibular region were studied. A retrospective analysis of 472 radical neck specimens obtained from 1975 to 1985 revealed 19 cases (4.0%) of cervical metastases limited to the submandibular triangle. Sources of these tumors included lip (3), buccal mucosa (4), nasal vestibule (1), floor of mouth (4), alveolar ridge (3), oral tongue (1), and unknown (3). It appears that solitary submandibular nodal metastases predominantly arise from sites in the oral or nasal cavity. This suggests that in patients with isolated submandibular lymph node metastases from occult primary sites, a more conservative therapeutic approach to potential primary sites is indicated after treatment of the metastatic focus.
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166
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Abemayor E. Instructional Courses, Volume 1, 1988. Ann Plast Surg 1990. [DOI: 10.1097/00000637-199002000-00020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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167
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Bredenkamp JK, Abemayor E, Wackym PA, Ward PH. Tonsillectomy under local anesthesia: a safe and effective alternative. Am J Otolaryngol 1990; 11:18-22. [PMID: 2108585 DOI: 10.1016/0196-0709(90)90165-r] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Tonsillectomy using local anesthesia (local tonsillectomy) is a safe and effective alternative to general anesthesia in the healthy cooperative teenage or adult patient. This retrospective analysis involved 64 local tonsillectomies performed over the past 7 years in a minor operating room using only local anesthesia with intravenous sedation. Operations were performed by residents in training as well as by experienced head and neck surgeons. Blood loss, morbidity, complications, and patient satisfaction were reviewed and compared with tonsillectomies done under general anesthesia. The average blood loss was 42 mL in the local tonsillectomy group with no cases of postoperative hemorrhage, compared with 198 mL in the general anesthesia group with two cases of postoperative hemorrhage. There was one major complication related to postoperative antibiotic use in the local anesthesia group, and follow-up interviews revealed that patients were satisfied with the procedure and would recommend and choose local anesthesia again. We conclude that local tonsillectomies have high patient acceptance and are associated with minimal morbidity and complications. Furthermore, they are cost-effective.
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168
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Canalis RF, Abemayor E, McClean P. Preservation of hearing in cholesteatomas with inner ear invasion. THE JOURNAL OF OTOLARYNGOLOGY 1989; 18:374-9. [PMID: 2687485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Two cases of inner ear destruction by cholesteatoma are presented. There was total demineralization of the cochlea in one and significant vestibular destruction in the other. Eradication and exteriorization of the disease was accomplished with preservation of hearing in both cases. Safe management was enhanced by aggressive infection control and accurate surgical planning aided by current imaging techniques. The factors which protect auditory function in these lesions remain unclear. However, the site and extent of the disease as well as local tissue reaction leading to separation of the inflammatory process from the sensory epithelium appear to play a significant role in preservation of hearing despite the presence of invasive, destructive disease.
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169
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Canalis RF, Gussen R, Abemayor E. Endolymphatic hydrops after fenestration: a temporal bone study with implications on the function of the utriculo-endolymphatic valve. Am J Otolaryngol 1989; 10:404-9. [PMID: 2596627 DOI: 10.1016/0196-0709(89)90036-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A temporal bone specimen demonstrating endolymphatic hydrops 13 years after fenestration of the lateral semicircular canal is presented. Fibro-osseous tissue extending from the lateral semicircular canal and reaching the vestibule produced fixation of the membranous wall of the utricle to the bony wall. Fixation and retraction of the utricule appears to have resulted in a permanently open utriculo-endolymphatic valve leaflet. Similar findings of fibro-osseous changes arising from the area of the crus commune and an open valve were found in a Meniere's disease specimen. The implications of these findings on the function of the valve are discussed.
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170
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Christianson R, Lufkin RB, Abemayor E, Hanafee W. IRM de la mandibule. Surg Radiol Anat 1989. [DOI: 10.1007/bf02098820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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171
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Abstract
Eighteen patients with abnormalities of the mandible and two normal volunteers were studied with MRI. Correlation was made with MR, CT, plain X-rays, clinical examination, and surgical findings when possible. In primary tumors of the mandible, MR was able to differentiate between solid and cystic lesions. In the cases of secondary invasion of the mandible by malignant tumors, MR was able to demonstrate replacement of the normal high signal bone marrow by low signal tumor. In some cases, the extent of marrow involvement shown on MR and confirmed at surgery was significantly underestimated by clinical examination, plain films, and CT. From this limited experience, it appears that MR may play an important role in imaging pathology of the mandible.
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172
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Abemayor E, Sidell N, Juillard G. Human medullary thyroid carcinoma. Initial characterization and in vitro differentiation of two new cell lines. ARCHIVES OF OTOLARYNGOLOGY--HEAD & NECK SURGERY 1989; 115:478-83. [PMID: 2538133 DOI: 10.1001/archotol.1989.01860280076020] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Medullary carcinoma of the thyroid (MCT), a tumor of calcitonin (CT)-secreting C cells, can display a variable malignant potential with poor prognosis linked to decreased cell differentiation. In vitro study of MCT has been hampered by the fact that few cell lines derived from this neoplasm have been available for study. Herein are reported the characteristics of two new lines derived from human MCT that are tumorigenic in athymic mice and do not secrete CT. After treatment with various concentrations of retinoic acid (a vitamin A derivative) and cyclic adenosine monophosphate, both lines exhibit the traits of more differentiated cells with a decrease in cellular proliferation and an increase in cytoplasmic CT content as shown by in situ immunoperoxidase staining. These cell lines should prove of great value in the study of the biology of MCT and the mechanisms underlying induced differentiation in this type of tumor.
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173
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Abemayor E, Sidell N. Human neuroblastoma cell lines as models for the in vitro study of neoplastic and neuronal cell differentiation. ENVIRONMENTAL HEALTH PERSPECTIVES 1989; 80:3-15. [PMID: 2538324 PMCID: PMC1567609 DOI: 10.1289/ehp.89803] [Citation(s) in RCA: 117] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Neuroblastoma is a childhood solid tumor composed of primitive cells derived from precursors of the autonomic nervous system. This neoplasm has the highest rate of spontaneous regression of all cancer types and has been noted to undergo spontaneous and chemically induced differentiation into elements resembling mature nervous tissue. As such, neuroblastoma has been a prime model system for the study of neuronal differentiation and the process of cancer cell maturation. In this paper we review those agents that have been described to induce the differentiation of neuroblastoma, with an emphasis on the effects and possible mechanisms of action of a group of related compounds, the retinoids. With this model system and the availability of subclones that are both responsive and resistant to chemically induced differentiation, fundamental questions regarding the mechanisms and processes underlying cell maturation have become more amenable to in vitro study.
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174
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Andrews JC, Abemayor E, Alessi DM, Canalis RF. Parotitis and facial nerve dysfunction. ARCHIVES OF OTOLARYNGOLOGY--HEAD & NECK SURGERY 1989; 115:240-2. [PMID: 2914097 DOI: 10.1001/archotol.1989.01860260114026] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Paralysis of the facial nerve in association with suppurative parotitis is rare, with only ten previously reported cases. In some situations, inflammation surrounding a benign neoplasm accounted for the observed paralysis. In this article, three new cases of parotitis with associated facial nerve dysfunction are described, none of which was associated with a neoplasm. In one, an occult abscess was present and in another an aggressive necrotizing process was seen. The treatment of this disease should initially be conservative management with high doses of wide-spectrum antibiotics. In the majority of cases, resolution of the facial paralysis should follow. However, persistence of a parotid mass with continued facial palsy mandates surgical exploration to exclude the presence of an underlying neoplasm.
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175
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Trapp T, Lufkin R, Abemayor E, Layfield L, Hanafee W, Ward P. A new needle and technique for MRI-guided aspiration cytology of the head and neck. Laryngoscope 1989; 99:105-8. [PMID: 2909813 DOI: 10.1288/00005537-198901000-00019] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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