Biomedical subjects
Publications and source records attributed to L Barnes.
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Two cases of mucoepidermoid carcinoma of the parotid gland associated with extensive central sclerosis and peripheral lymphoid response are reported. This unusual but distinctive variant of mucoepidermoid carcinoma can be difficult to recognize and may be confused with chronic sialoadenitis or even metastasis to an intraparotid lymph node.
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Lymphoepithelial carcinoma of the larynx, hypopharynx, and trachea is a rare neoplasm composed of large, poorly differentiated, nonkeratinized cells intermingled with small nonneoplastic lymphocytes and plasma cells. It is histologically similar to its more common counterpart occurring in the nasopharynx. In contrast to nasopharyngeal carcinoma, most cases have not been associated with Epstein-Barr virus (EBV), although rare cases have been reported to be EBV-positive. The diagnosis often requires immunohistochemistry or electron microscopy for confirmation. The neoplasm seems to behave in a fashion reminiscent of nasopharyngeal carcinoma. Lymph node metastasis occurs in the majority of patients, and eventual visceral dissemination occurs in one fourth. Radiotherapy is the main treatment for the primary tumor and regional metastases, but chemotherapy is indicated for more advanced disease. The initial stage is the primary determinant of prognosis. Death from disease occurs in about one third of patients.
BACKGROUND: Basal cell adenocarcinoma (BCAC) is a rare, recently described salivary gland tumor. The authors report the clinicopathologic features of 7 new cases and compare the results with 65 additional cases in the English literature to comprehend its natural history. METHODS: Seven cases were retrieved from the surgical pathology files at Presbyterian University Hospital and the Eye and Ear Institute Pavilion in Pittsburgh, Pennsylvania. The cases were accumulated between the years 1985 and 1995. Of these, five were outside consultations. RESULTS: The 6 women and 1 man ranged in age from 46 to 74 years and presented primarily with a slowly enlarging asymptomatic mass of either the parotid (6 cases) or submandibular gland (1 case). None had facial nerve paresis or cervical lymphadenopathy. Three tumors arose from preexisting basal cell adenomas. Two patients experienced local recurrences and one had distant metastasis. However, all the patients were alive and without known disease at last follow-up (average 30 months). CONCLUSIONS: Combining the current series with 65 additional cases in the literature indicated that BCAC is a low grade malignant tumor that occurs primarily in the parotid gland (89% of all cases) of older individuals (median 60 years) without gender predilection. Most arise de novo (77%), but occasionally some arise from preexisting basal cell adenomas (23%). Although local recurrences are common (37%), regional lymph node and distant metastasis are rare (8% and 4%, respectively). Local excision with tumor free margins is the treatment of choice.
Eight cases of lymphoepithelial carcinoma (LEC) of the larynx and hypopharynx were evaluated for clinicopathologic features, and the presence of the Epstein-Barr virus (EBV) and p53 alterations. The seven men and one woman, all of non-Asian descent, averaged 64 years of age. Eighty-eight percent had histologically confirmed cervical lymph node metastasis at diagnosis. None had systemic disease. Seven of eight patients available for follow-up (mean, 17.7 months) were alive and free of disease, although one did develop recurrent tumor in the neck. Four tumors were composed, histologically, of pure LEC. Four others had foci of both LEC and conventional squamous cell carcinoma. All eight tumors exhibited alterations in p53 expression, but none was positive for EBV. Combining these 8 cases with the 15 previously published cases in the English literature indicate that LEC in this site is a rare, rather aggressive tumor, primarily of older adults (mean, 62 years) with a propensity for early cervical lymph node metastasis and eventual distant dissemination and death from disease in about one third of patients. Although p53 alterations are common and of no apparent prognostic significance, LEC at this site seems to have little, if any, relationship to the EBV in patients of non-Asian origin.
BACKGROUND: Surgically induced ischemia and reperfusion is frequently accompanied by local and remote organ injury. It was hypothesized that this procedure may produce injurious oxidants such as hydrogen peroxide (H2O2), which, if unscavenged, will generate the highly toxic hydroxyl radical (.OH). Accordingly, it was proposed that tourniquet-induced exsanguination for limb surgery may be a useful ischemia-reperfusion model to investigate the presence of oxidants, particularly H2O2. METHODS: In ten patients undergoing knee surgery, catheters were placed in the femoral vein of the limb operated on for collection of local blood and in a vein of the arm for sampling of systemic blood. Tourniquet-induced limb exsanguination was induced for about 2 h. After tourniquet release (reperfusion), blood samples were collected during a 2-h period for measurement of H2O2, xanthine oxidase activity, xanthine, uric acid (UA), glutathione, and glutathione disulfide. RESULTS: At 30 s of reperfusion, H2O2 concentrations increased (approximately 90%) from 133 +/- 5 to 248 +/- 8 nmol.ml-1 (P < 0.05) in local blood samples, but no change was evident in systemic blood. However, in both local and systemic blood, xanthine oxidase activity increased approximately 90% (1.91 +/- 0.07 to 3.93 +/- 0.41 and 2.19 +/- 0.07 to 3.57 +/- 0.12 nmol UA.ml-1.min-1, respectively) as did glutathione concentrations (1.27 +/- 0.04 to 2.69 +/- 0.14 and 1.27 +/- 0.03 to 2.43 +/- 0.13 mumol.ml-1, respectively). At 5 min reperfusion, in local blood, H2O2 concentrations and xanthine oxidase activity peaked at 796 +/- 38 nmol.ml-1 (approximately 500%) and 11.69 +/- 1.46 nmol UA.ml-1.min-1 (approximately 520%), respectively. In local blood, xanthine and UA increased from 1.49 +/- 0.07 to 8.36 +/- 0.33 nmol.ml-1 and 2.69 +/- 0.16 to 3.90 +/- 0.18 mumol.ml-1, respectively, whereas glutathione and glutathione disulfide increased to 5.13 +/- 0.36 mumol.ml-1 and 0.514 +/- 0.092 nmol.ml-1, respectively. In systemic blood, xanthine oxidase activity peaked at 4.75 +/- 0.20 UA nmol.ml-1.min-1. At 10 min reperfusion, local blood glutathione and UA peaked at 7.08 +/- 0.46 mumol.ml-1 and 4.67 +/- 0.26 mumol.ml-1, respectively, while the other metabolites decreased significantly toward pretourniquet levels. From 20 to 120 min, most metabolites returned to pretourniquet levels; however, local and systemic blood xanthine oxidase activity remained increased 3.76 +/- 0.29 and 3.57 +/- 0.37 nmol UA.ml-1.min-1, respectively. Systemic blood H2O2 was never increased during the study. During the burst period (approximately 5-10 min), local blood H2O2 concentrations and xanthine oxidase activities were highly correlated (r = 0.999). CONCLUSIONS: These studies suggest that tourniquet-induced exsanguination for limb surgery is a significant source for toxic oxygen production in the form of H2O2 and that xanthine oxidase is probably the H2O2-generating enzyme that is formed during the ischemia-reperfusion event. In contrast to the reperfused leg, the absence of H2O2 in arm blood demonstrated a balanced oxidant scavenging in the systemic circulation, despite the persistent increase in systemic xanthine oxidase activity.
We describe a 42-year-old woman in whom extensive lymphangiectasia of the vulva developed after recurrent severe episodes of cellulitis, producing changes rather similar to those seen in lymphangioma circumscriptum. We suspect that an underlying lymphatic abnormality predisposed her to cellulitis, resulting in local lymphatic fibrosis and vulvar lymphangiectasia.
Basaloid squamous cell carcinoma is a recently recognized variant of squamous cell carcinoma. The lesion is histologically distinctive and manifests a predilection for the supraglottis, pyriform sinus, and tongue base. The immunohistochemical profile is discussed. The differential diagnoses include adenoid cystic carcinoma, small cell neuroendocrine carcinoma, basal cell adenocarcinoma, adenosquamous carcinoma, squamous cell carcinoma, spindle cell squamous carcinoma, mucoepidermoid carcinoma, and adenoid squamous cell carcinoma. Basaloid squamous cell carcinoma is a biologically high-grade tumor with a propensity for nodal as well as systemic metastases. It is a morphologic and phenotypic entity with a separate prognostic significance.
Since a great deal of confusion surrounds the different uses made by clinicians, pathologists, and biologists of the term, this paper clarifies the concept of "early" cancer of the larynx. Clinically, this is usually a glottic neoplasm in which full cordal mobility is still present; early supraglottic cancer is infrequent, and usually a chance finding. Whatever the site, early laryngeal cancer is a minimally invasive neoplastic lesion that does not invade the muscle or cartilage, but is still capable of metastasis. Being confined to the lamina propria, it is more than a carcinoma in situ but less than a deeply infiltrating carcinoma. Superficial extending carcinoma is therefore an early cancer. Biologically, early cancer belongs to stage II.
Intestinal-type adenocarcinoma (ITAC) of the nasal cavity and paranasal sinuses is an uncommon neoplasm manifesting a variety of histologic growth patterns, most of which are reminiscent of colorectal adenocarcinoma. To determine whether this morphologic resemblance is mirrored in equivalent genetic alterations, a series of ITAC was genotyped using archival, formalin-fixed tissues for point mutational damage in K-ras-2 oncogene and p53 tumor suppressor gene, forms of DNA damage frequently found in colorectal adenocarcinoma. In contrast to colorectal adenocarcinoma, which demonstrates K-ras-2 mutation in about 50% of cases, ITAC showed no evidence of K-ras-2 mutation. p53 mutations were present in 18% of ITAC (2 of 11) compared to more than 75% incidence of p53 mutation seen in colorectal adenocarcinoma. Fifty-eight percent of ITAC demonstrated scattered positive p53 immunohistochemical nuclear staining, but no mutations were identified in exon-5 through exon-8 by genotyping. There was no specific p53 alterations with respect to histologic subtype of ITAC. Although ITAC and colorectal adenocarcinoma are histologically similar, there are important differences at the genetic level based on expression of K-ras-2 and p53 abnormalities.
OBJECTIVE: To examine prospectively porphyrin metabolism in a human immunodeficiency virus (HIV)-positive population. SETTING: Specialist referral unit at the Department of Genitourinary Medicine, St James's Hospital, Dublin, Ireland. PATIENTS: Twenty-eight men and 5 women (age range, 18-35 years). Twenty-nine were current or previous intravenous drug abusers. Four were thought to have sexually acquired HIV infection. All had a history of acquired immunodeficiency syndrome-defining illnesses. The patients were selected as a consecutive sample from the inpatient department. Eligibility criteria were cooperation with urine and stool collection and confirmed HIV seropositivity. The patients were matched to 2 groups: 1 with normal results of porphyrin studies and the other with abnormal findings from porphyrin studies. INTERVENTION: None. MAIN OUTCOME MEASURES: Plasma, urine, and stool porphyrin excretion patterns. RESULTS: Of the 33 patients in the study, 13 (40%) had increased urinary porphyrin excretion. All but 2 of these patients were seropositive for hepatitis C virus. No study patient had clinical evidence of porphyria. Four patients (12%), however, had urine and stool porphyrin excretion patterns that were classic for porphyria cutanea tarda. All 4 of these patients were hepatitis C virus-positive. Patients with porphyrinuria had a greater degree of immunosuppression (P = .002) than those with normal porphyrin metabolism, and they were more likely to be taking zidovudine (P = .009). CONCLUSIONS: Commonly, porphyrin metabolism is abnormal in persons with established HIV infection. Hepatitis C may contribute to abnormal porphyrin metabolism. An unexpected number of patients studied had porphyrin excretion patterns that were characteristic of porphyria cutanea tarda, and all of these were hepatitis C virus-positive. A diagnosis of porphyria cutanea tarda, especially in a young patient, should prompt investigation for underlying HIV and hepatitis C virus infections. Dermatologists should be aware of the infectious risk associated with the vesicles and erosions in these patients. Porphyrin studies should be performed in any patient with HIV and photosensitivity.
Interleukin-6 (IL-6) is a multifunctional cytokine that regulates immune responses and acute phase reactions. It has demonstrated a growth factor function in several tumors, including those of salivary, plasma cell, and renal origin. We performed immunohistochemical staining for IL-6 localization on 57 salivary tumors. Reactivity was scored by intensity (0 to 4+) and percentage of cells staining, and the tumors were classified into three groups representing low (0 to 1+, 0% to 30%), moderate (2 to 3+, 31% to 75%), or high (> 3 to 4+, 76% to 100%) reactors. High reactivity was found in all primary pleomorphic adenomas (N = 10), five of eight recurrent pleomorphic adenomas, and all polymorphous low grade adenocarcinomas (N = 4). Moderate reactivity was observed in four of seven basal cell adenomas and three of five myoepitheliomas. Low reactivity characterized all acinic cell carcinomas (N = 3) and mucoepidermoid carcinomas (N = 3) as well as six of nine primary adenoid cystic carcinomas and all metastatic adenoid cystic carcinomas (N = 3). Carcinoma ex pleomorphic adenoma (N = 5) had three low and two moderate reactors. A pattern emerged in which the benign and low grade malignant tumors showed stronger reactivity than the metastatic or high grade malignant tumors. This suggests an inverse relationship between the presence of IL-6 and the biological aggressiveness of salivary gland tumors. The function of IL-6 in salivary gland neoplasia awaits further study and elucidation.
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An unusual case of post-radiation primary intranodal leiomyosarcoma of the cervical lymph node is presented. The patient was a 32-year-old white man who was treated in 1986 with hemiglossectomy and right neck dissection, followed by radiation therapy, for squamous cell carcinoma of the tongue. Six years later, he presented with an enlarged left cervical lymph node which on biopsy showed a high grade spindle cell malignant neoplasm. Immunohistochemistry and electron microscopic study verified the smooth muscle origin of the tumour. Extensive work-up for a second primary lesion was negative. Primary intranodal leiomyosarcoma is extremely rare. We briefly discuss the histological differential diagnosis of spindle cell lesions of lymph nodes, leiomyosarcoma of the vessel wall and radiation-associated sarcoma.
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