PubMed Health⌕ Search

Biomedical subjects

B Mackay

Publications and source records attributed to B Mackay.

At least 37 records · Page 2Linked to original sources
PubMed1993

Congenital hemangiopericytoma. An ultrastructural, immunocytochemical, and flow cytometric study.

Congenital (infantile) hemangiopericytoma is a rare soft-tissue tumor that has been described as a distinct subtype of the classic hemangiopericytoma. We report the ultrastructural, immunocytochemical, and flow cytometric features of a case diagnosed in a male neonate 3 days after birth. The tumor appeared structurally similar to its adult counterpart, meriting the designation hemangiopericytoma, but the improved prognosis that has been reported in young children supports according the infantile form the status of an entity rather than merging it with its adult counterpart.

Cytoskeletal Proteins↗
PubMed1992

Sarcomatoid carcinoma of the prostate. A clinicopathologic study of 12 patients.

Sarcomatoid carcinoma of the prostate is a rare tumor that can be difficult to distinguish from a true sarcoma. The authors report 12 patients in whom the typical light microscopic appearance of prostatic adenocarcinoma was accompanied by the appearance of spindled or pleomorphic sarcomatoid areas within the same specimen or in subsequent accessions. Immunostaining or electron microscopic study demonstrated epithelial differentiation within the sarcomatoid area(s) in 6 of the 11 patients in whom special studies were performed. All nine patients for whom follow-up data were available died of disease within 3 to 48 months (median time until death, 12.0 months) after the appearance of the sarcomatoid carcinoma, and the clinical course in each instance was characterized by aggressive local recurrence. Our experience confirms that sarcomatoid carcinoma of the prostate is an aggressive variant of prostatic adenocarcinoma.

Aged↗
PubMed1992

Small cell carcinoma of the urinary bladder. A clinicopathologic analysis of 22 cases.

Small cell carcinoma of the urinary bladder is an uncommon tumor. The authors report the clinicopathologic findings in a series of 22 cases. Fifteen men and 7 women were studied; their ages ranged from 51 to 87 years (mean, 62.4 years). The most frequent presentation was hematuria (94.4%). At diagnosis, three patients had Stage B disease, six had Stage C, and ten had Stage D (unknown stage in three). Histologically, 6 were oat cell type tumors, 11 were of intermediate cell type, and 5 were of combined cell type. Immunohistochemical studies demonstrated positivity for neuron-specific enolase in ten of ten cases, cytokeratin in seven of ten cases, chromogranin in eight of nine cases, serotonin in seven of nine cases, and S-100 protein in four of ten cases. Neuroendocrine differentiation was seen in five of seven cases examined by electron microscopy. Treatment and follow-up data were available for 19 patients: 10 (52.6%) were dead of disease, 5 (26.3%) were alive and well, 3 (15.8%) were alive with disease, and 1 (5.3%) died of an unrelated cause. The 2-year survival rate was 50% for patients with Stage B, 25% for patients with Stage C, and 33% for patients with Stage D disease. Although overall survival was poor, some cases responded well to therapy. Based on the authors' experience, radical cystectomy with adjuvant chemotherapy appears to be the treatment of choice.

Aged↗
PubMed1992

Pediatric lung transplantation: an emerging program.

Success has many measures, and team members each have personal criteria, but the success of our program is measured in the lives of our patients. To this end, every person associated with the program had a sense of ownership in it. It was imperative, in overcoming resistances, to treat people as individuals with valuable input, involve those affected in the planning, and provide complete and accurate information. Every person understood the process as a team effort. No one person acted alone, although key persons orchestrated the efforts of many. The instruments used were team building, communication, commitment, and collaboration. Problems and resultant pressures were viewed as challenges and opportunities for growth. When mistakes were made, we tried to learn from them, support each other, and move forward. Emphasis was on accomplishments, strengths, and unrealized potential. We learned from each other and from our patients. A close-knit team is an essential component of a successful program. The team is composed of professionals as active participants with mutual goals and a common purpose. Each member brings unique expertise, insights, personality, and experience in a cooperative venture to exchange information, identify problems, and reach a consensus. Time acts as a catalyst for members to learn to respect and appreciate each other. Cohesiveness evolves in a climate of acceptance, flexibility, and understanding. Members support and help each other. Consumers are involved with team members to participate in planning for care. In the space of 1 year, in spite of initial chaos from the Ready! Fire! Aim! approach, we have developed a sophisticated, comprehensive program for children with end-stage lung disease that can grow from a solid foundation. As we approach the second year and gain experience, we continue to evaluate our results and refine our aim.

Child↗
PubMed1991

Bronchioloalveolar adenocarcinoma with myoepithelial cells.

A unique variant of papillary lung carcinoma in a 58-year-old woman with both Clara cell and myoepithelial components is reported. The tumor was characterized by the presence of glandular spaces lined by two cell layers. The superficial (luminal) layer was made up of columnar cells with ultrastructural and immunohistochemical features of Clara cells, and occasional interspersed type 2 pneumocytes. The cells of the basal layer possessed ultrastructural and immunohistochemical features of myoepithelial cells. Myoepithelial cells have not previously been reported in a bronchioloalveolar adenocarcinoma.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1991

Paraganglioma of the urinary bladder: immunohistochemical, ultrastructural, and DNA flow cytometric studies.

Primary paraganglioma arises infrequently in the urinary bladder. We present the clinicopathologic, immunohistochemical, ultrastructural, and DNA flow cytometric findings in three cases (one man and two women). Ages at diagnosis were 19, 35, and 45 years. One female presented with paroxysmal headaches and hypertension that followed urination; the remaining two patients presented with hematuria. Immunohistochemical studies revealed positive reactivity for chromogranin (three patients), met-enkephalin (three), leu-enkephalin (three), vasoactive intestinal polypeptide (two), serotonin (one), and S-100 protein (one; sustentacular cells only). Neurosecretory granules were identified in all cases; in the patient with hypertension, the granules were small with eccentric cores similar to those of adrenal pheochromocytomas. A nondiploid DNA flow cytometric pattern was present in all three patients, an aneuploid pattern was present in two, and a tetraploid pattern was present in one. After diagnosis, one patient was alive without progression at 7 years, one died of an uncertain cause at 5 years, and one suffered multiple recurrences over a 24-year period before developing metastatic disease. While the presence of aneuploidy has been shown to be a predictor of malignant behavior in adrenal pheochromocytomas, our study illustrates that DNA ploidy cannot be used as a diagnostic criterion for malignancy in urinary bladder paraganglioma.

Adult↗
PubMed1991

Intraluminal crystalloids in struma ovarii. Immunohistochemical, DNA flow cytometric, and ultrastructural study.

We recently encountered a unique case of follicular variant of papillary carcinoma arising in struma ovarii that contained numerous intrafollicular crystalloids. There was no evidence of capsular or vascular invasion or metastases, though the DNA content of the papillary carcinoma was aneuploid. In contrast, diploid DNA was manifested in the histologically benign thyroid tissue. The nature of the crystalloids and the significance of aneuploid DNA content are discussed.

Aged↗
PubMed1990

Sarcomatoid carcinoma of the stomach. A report of three cases with immunohistochemical and ultrastructural observations.

The authors report three cases of sarcomatoid carcinoma arising in the stomach. This uncommon tumor is characterized by a mixture of malignant epithelial and spindle cell elements. All three tumors were large (average diameter, 5 cm) and infiltrated deep into the stomach wall. Two of the tumors had a polypoid configuration; the third was ulcerated and endophytic. Intestinal metaplasia was present adjacent to the tumor in all cases, with dysplasia in two. Immunohistochemical studies showed positivity for cytokeratin, carcinoembryonic antigen, and epithelial membrane antigen in the epithelial component of all tumors, and Leu-M1 was positive in the epithelial component of one. The spindle cell components contained vimentin, and in tumor 2, the spindle cell component was also positive for desmin. Two tumors showed focal positivity for cytokeratin in the spindle cells immediately adjacent to the epithelial component. Ultrastructurally, the spindle cell component of two tumors was composed of undifferentiated cells without specific epithelial or mesenchymal features. The third tumor contained occasional cells with features of myofibroblasts.

Aged↗
PubMed1990

Stromal neoplasms of the breast: a comparative flow cytometric study.

We analyzed 42 mammary spindle cell neoplasms (10 conventional fibroadenomas, 8 giant fibroadenomas, 17 cystosarcoma phyllodes, and 7 stromal sarcomas) by flow cytometry to assess the diagnostic and prognostic relevance of DNA content analysis in the pathologic evaluation of these lesions. Our data indicate that all fibroadenomas were diploid, cystosarcoma phyllodes displayed diploid and aneuploid DNA content irrespective of their histological categorization, and that stromal sarcomas were all aneuploid and clinically aggressive. Diploid cystosarcoma phyllodes were biologically indolent, whereas most of the aneuploid neoplasms killed their hosts (P = 0.03). The present study indicates that a DNA content abnormality it is a reliable marker of malignancy in these neoplasms, and it may identify subsets of patients with variable biologic courses within the histopathologic spectrum of cystosarcoma phyllodes.

Adenofibroma↗
PubMed1990

Synovial sarcoma: an immunohistochemical and ultrastructural study.

Thirty-nine primary synovial sarcomas (15 biphasic, 24 monophasic), and 19 metastatic synovial sarcomas were studied with a battery of antibodies directed to keratin, epithelial membrane antigen (EMA), carcinoembryonic antigen (CEA), vimentin, desmin, muscle-specific actin, smooth muscle actin, S-100 protein, Leu-7, chromogranin A, laminin, collagen IV, Ulex europaeus agglutinin I (UEAI), and the HMB-45 antimelanoma antibody. Twenty-two primary and 18 metastatic synovial sarcomas were also examined by electron microscopy. Epithelial and/or spindle cells in every biphasic tumor, primary and metastatic, reacted for keratin and EMA, but only six primary tumors (five biphasic and one monophasic) showed weak reactivity for CEA which, in the biphasic tumors, was confined to the epithelial component. Of the monophasic tumors, 15 primary (63%) and four metastatic (25%) stained for keratin, whereas seven primary (29%) and two metastatic (13%) tumors reacted for EMA. Only one primary monophasic synovial sarcoma stained for CEA. Tumors that stained for EMA or CEA also stained for keratin which is, therefore, the most useful epithelial marker. Immunostaining for epithelial markers, UEAI, collagen IV, and laminin serves to delineate the epithelial component when it is obscure in routine sections. Electron microscopy facilitates the diagnosis when epithelial markers are not expressed and aids in separating monophasic synovial sarcomas from other sarcomas that they resemble by light microscopy.

Adolescent↗
PubMed1990

Merkel cell carcinoma metastatic to the testis.

Tumor metastases to the testes are rare and are usually found incidentally at autopsy or after orchiectomy for prostatic carcinoma. It is even more unusual for testicular metastases to be clinically detected or symptomatic. The authors report two cases of clinically detected testicular metastases from Merkel cell carcinoma of the skin. Merkel cell carcinoma metastatic to the testes has not been reported previously. The two tumors, to some degree, resembled testicular lymphomas and the interstitial type of seminoma.

Aged↗
PubMed1990

Establishment of a new human pancreatic adenocarcinoma cell line, MDAPanc-3.

A new cell line was established from a liver metastasis of a human pancreatic adenocarcinoma. The cell line, MDAPanc-3, which arose from a moderately differentiated adenocarcinoma, produces carbonic anhydrase II mRNA, but no detectable levels of insulin or alpha amylase mRNA. The stem line chromosome number was determined to be 43, with six marker chromosomes. Growth of MDAPanc-3 is stimulated by cholecystokinin (CCK) fragment 26-33. The cell line will be useful in further studies on the mechanism(s) by which CCK stimulates growth of certain human pancreatic adenocarcinomas and normal human pancreatic exocrine tissue.

Adenocarcinoma↗
PubMed1989

Renal cell carcinoma metastatic to the thyroid.

Metastatic renal cell carcinoma to the thyroid is an uncommon occurrence that can cause clinical and pathologic problems in diagnosis. The authors report seven cases from the files of The University of Texas M.D. Anderson Cancer Center, Houston, Texas. Each presented clinically as a palpable thyroid nodule months or years after the primary renal cell carcinoma had been resected. Although renal cell carcinoma is more common in men, we found a female predominance of 6:1 in this series. These lesions appear as solitary "cold" nodules on iodine 131 scans and may be misdiagnosed as primary thyroid neoplasms, especially if the renal primary is still unrecognized. A correct diagnosis is important because surgical management can be curative. The diagnosis is facilitated by the use of fat stains, electron microscopic study, and immunoperoxidase stains.

Aged↗