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L J McGuire

Publications and source records attributed to L J McGuire.

At least 19 recordsLinked to original sources
PubMed1997

Bronchoalveolar lavage: comparison of nucleopore filters and direct smear preparations.

To determine whether cytopreparation affects the diagnostic yield of bronchoalveolar lavage specimens, we compared 50 lavage samples by using two methods. One nucleopore filter preparation and four direct slides were prepared on each sample submitted. All slides were stained by the Papanicolaou method. Assessment of cellularity, cellular preservation, and an independent diagnosis were rendered on each sample for both preparatory methods. Statistical analysis showed no difference in cellularity between the two methods (P = .06). The degree of nuclear and cytoplasmic preservation was higher using the direct method, although this did not appear to affect diagnosis in this study. One major discrepancy in diagnosis was observed between the two methods. By prospectively comparing nucleopore filter and direct preparation of bronchoalveolar lavages, we found that there was minimal affect on either cellularity or diagnosis. We conclude that either method delivers reliable cytologic results.

Bronchoalveolar Lavage↗
PubMed1995

DLD-1 and HCT-15 cell lines derived separately from colorectal carcinomas have totally different chromosome changes but the same genetic origin.

Aneuploid DLD-1 and HCT-15 cell lines independently derived from a colon carcinoma by two researchers lacked a common marker chromosome or a concurrent numerical change. To further look into the genetic identity of these two cell lines, we used chromosome painting with fluorescence in situ hybridization (FISH) and confirmed the G-band identification on all chromosome changes. We have also found comparable results between these two cell lines on C-/Q- polymorphic bands of several chromosomes, and electrophoretic patterns of restriction fragment-length polymorphisms (RFLPs) from eight Y-chromosome-specific DNA probes with 13 restriction enzymes. These results strongly suggest that DLD-1 and HCT-15 are identical genetically. Clearly, cell lines bearing totally unrelated changes in karotypes can be generated from the same cancer specimen.

Blotting, Southern↗
PubMed1992

Cytodiagnosis of lesions presenting as salivary gland swellings: a report of seven cases.

The cytologic and histologic findings of seven cases presenting clinically as salivary gland swellings are described. These included two cases of pilomatrixoma of skin in the parotid region, two cases of neurilemmoma in the submandibular area, a case of Kimura's disease in the peri-mandibular gland lymphoid tissue, a case of Castleman's disease in intraparotid lymph node, and a case of branchial cleft cyst in the parotid region. It is important to recognize lesions that masquerade as salivary gland tumors so that misdiagnosis and overdiagnosis on smears can be avoided and the patients can be treated appropriately.

Adolescent↗
PubMed1991

Tumor growth fraction in cervical carcinoma.

Thirty-one cervical carcinomas have been studied immunohistochemically to determine tumor growth fraction by using the monoclonal antibody Ki-67, which reacts with a nuclear antigen expressed only by proliferating cells. The growth fraction of individual tumor is estimated as the percentage of stained nuclei in a population of 1000 tumor cells. There is a good correlation of the growth fraction measured by Ki-67 with mitotic index and high histological grade of cervical carcinoma. This study, together with that of D. C. Brown, D. Cole, K. C. Gatter, and D. Y. Mason [Brit. J. Cancer 57(2), 178-181 (1988)], shows the usefulness of Ki-67 in the evaluation of growth fraction in cervical carcinoma.

Adenocarcinoma↗
PubMed1990

Solitary fibrous tumor of pleura: expression of cytokeratins.

A case of solitary fibrous tumor of the pleura (SFT) is presented. The histogenesis of this uncommon tumor is debated with most investigators favouring origin in submesothelial fibroblasts. Part of the evidence supporting this has been the persistent negativity of the tumor cells for cytokeratin--a feature militating against origin in mesothelial-lining cells. Our case shows unequivocal focal cytokeratin positivity in tumor cells; we feel that although this indicates mesothelial differentiation it does not militate against origin in submesothelial fibroblasts since, in reactive conditions, these are capable of mesothelial differentiation including expression of cytokeratin. Indeed, it reinforces the hypothesis that SFT is of submesothelial origin. Solitary fibrous tumors can be cellular and atypical. The reactivity of the tumor with cytokeratin, albeit rarely, should be considered in differentiating SFT from sarcomatoid mesothelioma.

Aged↗
PubMed1990

The histopathologic diagnosis of nasopharyngeal carcinoma.

NPC is common in Hong Kong. In the broad sense, NPC includes keratinizing squamous cell carcinomas, nonkeratinizing carcinomas, undifferentiated carcinomas, and adenocarcinomas. It is mainly the undifferentiated carcinoma that is prevalent in the Hong Kong region. We report our histologic experiences with nasopharyngeal malignancies, emphasizing the undifferentiated carcinomas that make up 82.4% of all nasopharyngeal malignancies in the Prince of Wales Hospital, Hong Kong. Important features of histopathologic diagnosis of NPC are discussed in the context of the literature.

Adenocarcinoma↗
PubMed1989

Anaplastic large cell Ki-1 lymphoma. Delineation of two morphological types.

This report describes 16 cases of the recently recognized anaplastic large cell Ki-1 lymphoma. The disease showed a male:female ratio of 2.2:1 and a bimodal age distribution with peaks in the third and eighth decades. The clinical presentation was highly variable, with lymph node, skin, bone and gastrointestinal tract being the most commonly affected sites. The lymph nodes usually showed subtotal or sinusoidal involvement, and parenchymal fibrosis was common. The large neoplastic cells were almost invariably admixed with many reactive small lymphocytes, histiocytes and/or neutrophils. Two cytological types could be delineated: type I (pale cell, four cases) consisted of large polygonal cells with distinct pink-staining cell membrane and pale cytoplasm and pleomorphic nuclei showing marked chromatin clearing; and type II (basophilic cell, 12 cases) consisted of round or oval cells with basophilic cytoplasm and/or paranuclear pale hof, pleomorphic nuclei often reniform or lobulated and with frequent multinucleated wreath-like and Reed-Sternberg-like cells. Immunohistochemical studies showed that nine cases (56.3%) exhibited a T-cell phenotype, three cases (18.8%) each exhibited a B-cell or null-cell phenotype, while one case exhibited both T- and B-cell markers. Cutaneous involvement at presentation was associated with a favourable outcome, and spontaneous regression was common. For patients with non-cutaneous presentation, the prognosis was relatively good for young patients treated with aggressive chemotherapy, but was grave for old patients.

Adolescent↗
PubMed1989

Intrathoracic stapled anastomosis after oesophagectomy for cancer.

Fifty consecutive oesophagectomies for cancer are reported which were performed using a two-stage technique with an intrathoracic stapled anastomosis. The oesophagus was resected through a right thoracotomy. Continuity was restored using orthotopic stomach, mobilized through an abdominal incision and anastomosed to the oesophagus at the apex of the thorax. No deaths occurred within 30 days, but two patients died without leaving hospital. Routine contrast study revealed no anastomotic leaks. Major complications were: chylothorax (one), transient bilateral recurrent laryngeal nerve palsy (one), anastomotic bleed (one), respiratory failure (one) and brain abscess (one). Four upper resection margins contained tumour (all in middle third tumours). With this technique, a reliable anastomosis can be made high in the chest. The amount of oesophagus removed is comparable with that obtained with the 'three-stage' or transhiatal procedures. The problem of occult submucosal spread in oesophageal tumours remains.

Adult↗
PubMed1989

Coexpression of cytokeratin and vimentin.

The reported incidence of cytokeratin and vimentin intermediate filament coexpression is rapidly expanding. An up-do-date list of the instances in which this occurs is presented and the implications of this event are discussed.

Adult↗
PubMed1988

Primary malignant lymphoma of the deep tissues of the hand.

A 39-year-old tailor was seen initially with primary extranodal malignant lymphoma of the deep soft tissues of the right hand. The diagnosis was confirmed by immunocytochemical staining technique on the biopsy material. Review of the literature showed that this is a rare presentation. The prognosis is related to histologic grading. The patient received radiotherapy and the lesion responded rapidly. He was free of the disease 1 year later.

Adult↗
PubMed1988

Epstein-Barr virus genome in thymoma and thymic lymphoid hyperplasia.

In a study of 23 consecutive thymectomies from patients with myasthenia gravis (MG), 10 (43.5%) were thymomas, 8 (34.8%) were thymic lymphoid hyperplasia (TLH), and 5 (21.7%) were normal/involuted thymuses. The incidence of thymoma in MG appears to be considerably higher in Hong Kong than in similar series from Western countries. Six patients from this group were examined for the presence of Epstein-Barr virus (EBV) genome by Southern blot, as were a thymoma from a patient without MG, a patient with TLH in the absence of MG, and 3 normal control thymuses. All 3 thymomas (2 of 2 with MG, 1 of 1 without MG), 2 of 4 TLH with MG, and 1 of 1 TLH without MG were positive for EBV genome. Thymoma should be included, along with nasopharyngeal carcinoma and malignant lymphoepithelial lesions of the salivary gland, as EBV-related epithelial tumors, all of which are prevalent in this region.

Adult↗
PubMed1978

Repeated partial hepatectomy as a promoting stimulus for carcinogenic response of liver to nitrosamines in rats.

Partial hepatectomy 24 h before a single i.p. dose of dimethylnitrosamine, diethylnitrosamine or ethylmethylnitrosamine increased the carcinogenic response in the liver of rats as determined by the number of tumours and the number of "focal proliferations" produced. Secondly, in rats given a single i.p. dose of diethylnitrosamine, 3 partial hepatectomies 5, 10 and 15 weeks after dosing the animals increased the carcinogenic response in the liver. The stimulus of repeated partial hepatectomy therefore appears to act as a "promoting agent" for liver carcinogenesis, that is if the single dose of diethylnitrosamine is regarded as an "initiating agent" in the terms of the two-stage hypothesis.

Animals↗
PubMed1978

Influence of repeated liver regeneration on hepatic carcinogenesis by diethylnitrosamine in mice.

In mice given a single dose of diethylnitrosamine, a hepatonecrotic dose of carbon tetrachloride, 5 weeks after dosing with DEN and repeated 6 times at 4-weekly intervals, augmented the tumour yield in the livers. A single hepatonecrotic dose of CCl4 24 h before a single dose of DEN also increased the number of tumours produced. The effect of the repeated administration of CCl4 after the dose of DEN occurred in addition to, and was therefore independent of, the enhancing effect of a single dose of CCl4 before DEN. These results may be interpreted as implying (1) that the liver in the regenerative phase after a hepatonecrotic dose of CCl4 is more susceptible to an initiating action of DEN, i.e. produces more potential foci of tumour growth than in the normal liver and (2) that the repeated doses of CCl4 leading to repeated phases of regeneration, after the dose of DEN, provide a promoting stimulus.

Animals↗