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Yuen PW, Lam KY, Chan AC, Wei WI, Lam LK. Clinicopathological analysis of local spread of carcinoma of the tongue. Am J Surg 1998; 175:242-4. [PMID: 9560130 DOI: 10.1016/s0002-9610(97)00282-1] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND The aims of the study are three-dimensional analysis of mode and distance of local spread of oral tongue carcinoma. METHODS The glossectomy specimens were examined in the coronal plane in 3 mm thickness section. RESULTS There were 50 glossectomy specimens. The maximum spread was 1.8 cm. Ninety-six percent of specimens had local spread within 1.2 cm. The distance of spread was not correlated with tumor size, including the diameter, depth, and volume. The incidence of local recurrence was 27% with positive histological margin. Perineural infiltration was the most important prognostic factor for local recurrence and survival. CONCLUSIONS A minimum of 1.5-cm surgical resection margin is recommended. A smaller margin is not recommended as it has significant risk of local recurrence. A maximum of 2-cm surgical resection margin is recommended; larger margins will increase the surgical morbidity without a significant advantage of local control.
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102
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Ng EK, Sung JJ, Ling TK, Ip SM, Lau JY, Chan AC, Liew CT, Chung SC. Helicobacter pylori and the null genotype of glutathione-S-transferase-mu in patients with gastric adenocarcinoma. Cancer 1998. [PMID: 9445181 DOI: 10.1002/(sici)1097-0142(19980115)82:2<268::aid-cncr4>3.0.co;2-n] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND Chronic Helicobacter pylori infection now is recognized as an important causative agent for gastric carcinoma. However, only a small minority of infected individuals develop the malignancy, even in areas with a high prevalence of gastric carcinoma. It has been postulated that the absence of glutathione-S-transferase-mu (GST-mu), which impairs detoxification of exogenous carcinogens, might predispose some infected individuals to the development of gastric carcinoma. METHODS Patients with histologically confirmed adenocarcinoma of the stomach were tested for H. pylori infection and the GST-mu genotype. Prevalence of GST-mu gene deletion was compared with the H. pylori status of the patients. A group of gender- and age-matched control subjects with known H. pylori-related nonulcer dyspepsia also were tested for the GST-mu genotype and compared with patients with H. pylori positive carcinoma. RESULTS Fifty-one patients with gastric adenocarcinoma were enrolled into the study. Thirty-five were found to have H. pylori in the resected specimens. The null genotype of GST-mu was significantly more common among those patients with H. pylori positive carcinoma compared with the H. pylori negative group (65.7% vs. 31.3%; P < 0.05). Homozygous deletion of GST-mu was significantly higher in the H. pylori positive carcinoma patients than in the H. pylori-infected, nonmalignant control group (65.7% vs. 37.1%; P < 0.05). CONCLUSIONS The null genotype for GST-mu is found more commonly in gastric carcinoma associated with H. pylori infection. The absence of the GST-mu enzyme may increase the risk of the development of gastric carcinoma in these patients.
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Ng EK, Sung JJ, Ling TK, Ip SM, Lau JY, Chan AC, Liew CT, Chung SC. Helicobacter pylori and the null genotype of glutathione-S-transferase-mu in patients with gastric adenocarcinoma. Cancer 1998. [PMID: 9445181 DOI: 10.1002/(sici)1097-0142(19980115)82: 2<268: : aid-cncr4>3.0.co; 2-n] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Chronic Helicobacter pylori infection now is recognized as an important causative agent for gastric carcinoma. However, only a small minority of infected individuals develop the malignancy, even in areas with a high prevalence of gastric carcinoma. It has been postulated that the absence of glutathione-S-transferase-mu (GST-mu), which impairs detoxification of exogenous carcinogens, might predispose some infected individuals to the development of gastric carcinoma. METHODS Patients with histologically confirmed adenocarcinoma of the stomach were tested for H. pylori infection and the GST-mu genotype. Prevalence of GST-mu gene deletion was compared with the H. pylori status of the patients. A group of gender- and age-matched control subjects with known H. pylori-related nonulcer dyspepsia also were tested for the GST-mu genotype and compared with patients with H. pylori positive carcinoma. RESULTS Fifty-one patients with gastric adenocarcinoma were enrolled into the study. Thirty-five were found to have H. pylori in the resected specimens. The null genotype of GST-mu was significantly more common among those patients with H. pylori positive carcinoma compared with the H. pylori negative group (65.7% vs. 31.3%; P < 0.05). Homozygous deletion of GST-mu was significantly higher in the H. pylori positive carcinoma patients than in the H. pylori-infected, nonmalignant control group (65.7% vs. 37.1%; P < 0.05). CONCLUSIONS The null genotype for GST-mu is found more commonly in gastric carcinoma associated with H. pylori infection. The absence of the GST-mu enzyme may increase the risk of the development of gastric carcinoma in these patients.
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Tang JC, Ho FC, Chan AC, Srivastava G. Clonality of lymphomas at multiple sites in SJL mice. J Transl Med 1998; 78:205-12. [PMID: 9484718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
SJL mice are an inbred strain of mice with a high incidence of spontaneous lymphomas of B-cell type often involving multiple abdominal organs, and are therefore a useful model for studying the clonal relationship among lymphomas at multiple sites. Thirteen SJL mice with well-developed tumors were killed at a median age of 56 weeks. Autopsy samples were taken from various enlarged lymphoid organs, and the histologic appearance of lymphomas was recorded. Using rearrangements of immunoglobulin genes (heavy and kappa-light chain genes) and integration patterns of murine leukemia virus as clonal markers, 7 of the 13 informative mice showed complete clonal identity among the different sites selected from each mouse; 5 of 13 mice demonstrated at least one shared clonal band with one or more markers being different among the different sites. The histologic appearance of the lymphomas from the various sites was found to be heterogeneous, even when there was clonal identity. These findings suggest that SJL lymphomas in multiple sites within one mouse are usually derived from a single clone but may show development of subclones within a major clonal population, thus supporting the notion that clonal evolution is a common event in the course of development of lymphoid neoplasia.
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105
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Ng EK, Sung JJ, Ling TK, Ip SM, Lau JY, Chan AC, Liew CT, Chung SC. Helicobacter pylori and the null genotype of glutathione-S-transferase-mu in patients with gastric adenocarcinoma. Cancer 1998; 82:268-73. [PMID: 9445181 DOI: 10.1002/(sici)1097-0142(19980115)82:2<268::aid-cncr4>3.0.co;2-n] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Chronic Helicobacter pylori infection now is recognized as an important causative agent for gastric carcinoma. However, only a small minority of infected individuals develop the malignancy, even in areas with a high prevalence of gastric carcinoma. It has been postulated that the absence of glutathione-S-transferase-mu (GST-mu), which impairs detoxification of exogenous carcinogens, might predispose some infected individuals to the development of gastric carcinoma. METHODS Patients with histologically confirmed adenocarcinoma of the stomach were tested for H. pylori infection and the GST-mu genotype. Prevalence of GST-mu gene deletion was compared with the H. pylori status of the patients. A group of gender- and age-matched control subjects with known H. pylori-related nonulcer dyspepsia also were tested for the GST-mu genotype and compared with patients with H. pylori positive carcinoma. RESULTS Fifty-one patients with gastric adenocarcinoma were enrolled into the study. Thirty-five were found to have H. pylori in the resected specimens. The null genotype of GST-mu was significantly more common among those patients with H. pylori positive carcinoma compared with the H. pylori negative group (65.7% vs. 31.3%; P < 0.05). Homozygous deletion of GST-mu was significantly higher in the H. pylori positive carcinoma patients than in the H. pylori-infected, nonmalignant control group (65.7% vs. 37.1%; P < 0.05). CONCLUSIONS The null genotype for GST-mu is found more commonly in gastric carcinoma associated with H. pylori infection. The absence of the GST-mu enzyme may increase the risk of the development of gastric carcinoma in these patients.
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Au WY, Chan AC, Lie AK, Chen FE, Liang R, Kwong YL. Recurrent isolated extramedullary relapses as granulocytic sarcomas following allogeneic bone marrow transplantation for acute myeloid leukemia. Bone Marrow Transplant 1998; 21:205-8. [PMID: 9489639 DOI: 10.1038/sj.bmt.1701043] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Isolated extramedullary relapses as granulocytic sarcomas (GS) following allogeneic bone marrow transplantation (BMT) for acute myeloid leukemia (AML) are rare events. We describe three such patients who presented with a unique pattern of GS relapse post-BMT. The clinical features included repeated relapses in multiple sites, absence of marrow involvement, and prolonged survival. Fluorescence in situ hybridization (FISH) demonstrated persistence of donor hematopoiesis despite disseminated GS. The findings indicated that a graft-versus-leukemia (GVL) effect might operate more strongly in the marrow than in peripheral sites. Finally, our observations suggest that isolated GS relapses after BMT might be compatible with long survivals, and that in patients with marrow hematopoiesis of donor origin, augmentation of the GVL effect might be of use.
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Cheung AN, Chan AC, Chung LP, Chan TM, Cheng IK, Chan KW. Post-transplantation lymphoproliferative disorder of donor origin in a sex-mismatched renal allograft as proven by chromosome in situ hybridization. Mod Pathol 1998; 11:99-102. [PMID: 9556430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We report a case of post-transplantation B-cell lymphoproliferative disorder (PTLPD) associated with Epstein-Barr virus (EBV) that developed in a renal allograft 5 months after transplantation. The lesion had a histologic appearance of diffuse large B-cell lymphoma with monoclonality demonstrated by in situ hybridization (ISH) for kappa and lambda mRNA. Both the male donor and the female recipient were EBV seropositive. The lymphoid cells in this lesion was proven to be of donor origin by ISH for the human Y chromosome on the paraffin-embedded sections of the allograft. The recipient of the other kidney from the same donor did not have evidence of lymphoma, and the patient was also free from disease 2 years after surgical removal of the lymphoma This case is an unusual PTLPD of donor origin; the majority of such lesions in solid organ transplantations are of recipient origin. Our findings demonstrate that the origin of PTLPD can be documented in selected cases using ISH with probes to the Y chromosome.
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Liang R, Chan WP, Kwong YL, Chan AC, Xu WS, Au WY, Srivastava G, Ho FC. Bcl-6 gene hypermutations in diffuse large B-cell lymphoma of primary gastric origin. Br J Haematol 1997; 99:668-70. [PMID: 9401082 DOI: 10.1046/j.1365-2141.1997.4443254.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The presence of the bcl-6 gene hypermutation was studied in 40 Hong Kong Chinese patients with diffuse large B-cell lymphoma. The primary sites of involvement were nodal in 18 cases and gastric in 22. Hypermutations at the E1.11 segment of bcl-6 gene were detectable in 16/22 (73%) primary gastric and 4/18 (22%) primary nodal lymphoma (P<0.01). Three of the 22 cases of primary gastric but none of the nodal lymphoma had mutations at E1.12. The proportion of hypermutated cases in the group with bcl-6 gene rearrangement was similar to that of the germ-line group (70% v 75%). High frequency of bcl-6 gene hypermutations was found in diffuse large B-cell lymphoma of the stomach and they were independent of rearrangement of the gene as detected by Southern analysis. Unlike gene rearrangement, hypermutations of the bcl-6 gene did not appear to carry any prognostic significance clinically.
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Lai PB, Leung KN, Chan AC, Leow CK, Lau WY. Case 18. Rupture of a splenic artery pseudoaneurysm into a pancreatic pseudocyst. Can J Surg 1997; 40:412, 430. [PMID: 9416249 PMCID: PMC3950028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
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110
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Chiang AK, Chan AC, Srivastava G, Ho FC. Nasal T/natural killer (NK)-cell lymphomas are derived from Epstein-Barr virus-infected cytotoxic lymphocytes of both NK- and T-cell lineage. Int J Cancer 1997; 73:332-8. [PMID: 9359478 DOI: 10.1002/(sici)1097-0215(19971104)73:3<332::aid-ijc5>3.0.co;2-0] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The cellular nature of nasal T/natural killer (NK)-cell lymphomas (NLs) remains controversial. It is still debatable whether these represent T-cell lymphomas with extensive loss of surface antigens or are, in fact, true NK-cell lymphomas. They are associated closely with Epstein-Barr virus (EBV), to the extent that EBV-encoded small non-polyadenylated RNAs (EBER) expression can be used as a marker for the neoplastic cells. The cell lineage of this group of lymphomas was examined further by correlating immunophenotype, genotype and EBV status with the expression of cytotoxic granule-associated proteins, perforin and T-cell intracellular antigen-1 (TIA-1) in 13 cases of NL. Combined immunophenotypic and gene rearrangement analyses demonstrated that NLs can be identified clearly as either NK-cell or T-cell tumours. Nasal NK-cell lymphomas lacked clonal rearrangement of both T-cell receptor (TCR) gamma and immunogloulin heavy chain (IgH) genes and were either CD3(Leu4)-CD56+ (8 cases) or CD3(Leu4)+CD56+ (2 cases), whereas nasal T-cell lymphomas had rearranged TCRgamma and germ-line IgH genes and were either CD3(Leu4)+CD56+ (2 cases) or CD3(Leu4)+CD56- (1 case). Immunohistochemical (IH) studies showed that both perforin and TIA-1 were expressed universally in NL, irrespective of NK- or T-cell lineage. Dual labelling of TIA-1 by IH and EBER by in situ hybridisation demonstrated that the granule proteins were expressed predominantly by the EBER+ tumour cells. Our results indicate that NLs are derived from EBV-infected cytotoxic lymphocytes of both NK- and T-cell lineage. We postulate that cytotoxic lymphocytes generated during the cellular immune response to EBV infection or re-activation at the nasal region themselves may become targets for EBV infection and subsequent transformation.
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MESH Headings
- Gene Rearrangement, B-Lymphocyte, Heavy Chain
- Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor
- Genotype
- Herpesvirus 4, Human
- Humans
- Killer Cells, Natural/immunology
- Killer Cells, Natural/pathology
- Lymphoma, T-Cell/genetics
- Lymphoma, T-Cell/immunology
- Lymphoma, T-Cell/pathology
- Lymphoma, T-Cell/virology
- Membrane Glycoproteins/analysis
- Membrane Proteins/analysis
- Neoplasm Proteins/analysis
- Nose Neoplasms/genetics
- Nose Neoplasms/immunology
- Nose Neoplasms/pathology
- Nose Neoplasms/virology
- Perforin
- Phenotype
- Poly(A)-Binding Proteins
- Pore Forming Cytotoxic Proteins
- Proteins
- RNA-Binding Proteins/analysis
- Ribosomal Proteins
- T-Cell Intracellular Antigen-1
- T-Lymphocytes, Cytotoxic/immunology
- T-Lymphocytes, Cytotoxic/pathology
- T-Lymphocytes, Cytotoxic/virology
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Fu C, Chan AC. Identification of two tyrosine phosphoproteins, pp70 and pp68, which interact with phospholipase Cgamma, Grb2, and Vav after B cell antigen receptor activation. J Biol Chem 1997; 272:27362-8. [PMID: 9341187 DOI: 10.1074/jbc.272.43.27362] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Tyrosine phosphorylation of cellular proteins mediates the assembly and localization of effector proteins through interactions facilitated by modular Src homology 2 (SH2) and phosphotyrosine binding domains. We describe here two tyrosine-phosphorylated proteins with Mr values of 70,000 and 68,000 that interact with Grb2, phospholipase C (PLCgamma1 and PLCgamma2), and Vav after B cell receptor cross-linking. The interaction of pp70 and pp68 with PLC and Vav is mediated by the carboxyl-terminal SH2 domain of PLC and the SH2 domain of Vav. In contrast, the interaction of pp70 and pp68 with Grb2 requires cooperative binding of the SH2 and SH3 domains of Grb2. Western blot analysis demonstrated that neither pp70 nor pp68 represented the recently described linker protein SLP-76, which binds Grb2, PLC, and Vav in T cells after T cell receptor activation. Moreover, SLP-76 protein was not detected in a number of B cell lines or in normal mouse B cells. Hence, we propose that pp70 and pp68 likely represent B cell homologs of SLP-76 which facilitate and coordinate B cell activation.
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Tran K, Lee E, Wong J, Man RY, Jay FT, Chan AC, Choy PC. Vitamin E (alpha-tocopherol) enhances arachidonic acid release in rat heart myoblastic cells through the activation of cytosolic phospholipase A2. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1997; 407:123-9. [PMID: 9321942 DOI: 10.1007/978-1-4899-1813-0_19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Cheng AM, Negishi I, Anderson SJ, Chan AC, Bolen J, Loh DY, Pawson T. The Syk and ZAP-70 SH2-containing tyrosine kinases are implicated in pre-T cell receptor signaling. Proc Natl Acad Sci U S A 1997; 94:9797-801. [PMID: 9275205 PMCID: PMC23271 DOI: 10.1073/pnas.94.18.9797] [Citation(s) in RCA: 140] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
An early stage in thymocyte development, after rearrangement of the beta chain genes of the T cell receptor (TCR), involves expression of the pre-TCR complex and accompanying differentiation of CD4(-)CD8(-) double negative (DN) cells to CD4(+)CD8(+) double positive (DP) cells. The ZAP-70 and Syk tyrosine kinases each contain two N-terminal SH2 domains that bind phosphorylated motifs in antigen receptor subunits and are implicated in pre-T receptor signaling. However, mice deficient in either ZAP-70 or Syk have no defect in the formation of DP thymocytes. Here we show that, in mice lacking both Syk and ZAP-70, DN thymocytes undergo beta chain gene rearrangement but fail to initiate clonal expansion and are incapable of differentiating into DP cells after expression of the pre-TCR. These data suggest that the ZAP-70 and Syk tyrosine kinases have crucial but overlapping functions in signaling from the pre-TCR and hence in early thymocyte development.
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D'Orazio PA, Maley TC, McCaffrey RR, Chan AC, Orvedahl D, Foos J, Blake D, Degnan S, Benco J, Murphy C, Edelman PG, Ludi H. Planar (bio)sensors for critical care diagnostics. Clin Chem 1997; 43:1804-5. [PMID: 9299990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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115
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Gong Q, White L, Johnson R, White M, Negishi I, Thomas M, Chan AC. Restoration of thymocyte development and function in zap-70-/- mice by the Syk protein tyrosine kinase. Immunity 1997; 7:369-77. [PMID: 9324357 DOI: 10.1016/s1074-7613(00)80358-1] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The Syk family of protein tyrosine kinases, consisting of ZAP-70 and Syk, associate with the pre- and alphabeta T cell antigen receptors (TCRs) and undergo tyrosine phosphorylation and activation following receptor engagement. Thymocyte development in zap-70-/- mice is blocked at the CD4+CD8+ TCR(lo) stage. The presence of Syk in the thymus has raised the possibility that Syk may be able to mediate TCR function. To determine if Syk can play a role in thymocyte development, we generated zap-70-/- mice expressing a human syk cDNA. Syk expression restored both thymocyte development and function. In addition, Syk function required the CD45 transmembrane protein tyrosine phosphatase. Hence, ZAP-70 and Syk can play overlapping functions and exhibit similar regulatory mechanisms in mediating alphabeta T cell development.
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Abstract
Much has been learned over the past few years about how protein tyrosine kinases mediate pre-TCR and mature alphabetaTCR function. The highlights include understanding the roles and the distinct effects of the Src and Syk families of protein tyrosine kinases in thymocyte development and function.
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Abstract
Two cases of fatal strongyloidiasis associated with diabetes mellitus and malnutrition are reported. The patients presented with repeated vomiting and upper gastrointestinal bleeding respectively. Unusual findings in these two patients included: unexplained peripheral leukocytosis, pulmonary infiltrates, gastric aspirate leukocytosis, progression of gastrointestinal symptoms and concurrent presence of adult worms, eggs, filariform and rhabditiform larvae of Strongyloides stercoralis in alimentary canal specimens. Both patients succumbed while receiving treatment with mebendazole. The present report illustrates that unexplained gastrointestinal symptoms with extensive scratch marks below the umbilicus can be important clues to early diagnosis of the disease. In addition, the various presentations of S. stercoralis infestation are discussed with reference to predisposing factors. Current trends in laboratory diagnosis and therapeutic considerations are also delineated.
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Abstract
Conventional surgical access to the oesophagus often requires a thoracotomy. The application of techniques borrowed from laparoscopic surgery allows transthoracic dissection of oesophagus without thoracotomy. These techniques are useful in treatment of oesophageal leiomyomas, motility disorders and iatrogenic perforations. Oesophageal resection for cancer can be accomplished using minimal access, either thoracoscopically or with the aid of an operating mediastinoscope. Whether these techniques should replace transthoracic or transhiatal oesophagectomy for most patients with cancer remains to be seen.
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119
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Lau JY, Sung JJ, Chan AC, Lai GW, Lau JT, Ng EK, Chung SC, Li AK. Stigmata of hemorrhage in bleeding peptic ulcers: an interobserver agreement study among international experts. Gastrointest Endosc 1997; 46:33-6. [PMID: 9260702 DOI: 10.1016/s0016-5107(97)70206-2] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND Stigmata of hemorrhage predict rebleeding and outcome of patients with bleeding peptic ulcers. There are variabilities in reported incidences of stigmata and their respective rebleeding risks. We sought to study the interobserver agreement among experts. METHODS Between June 1994 and July 1994, 100 consecutive patients with bleeding peptic ulcers underwent videoendoscopy within 24 hours of their admissions. An edited videotape of these ulcers was compiled and sent to an international panel of 14 experts. They independently rated these ulcers exclusively into one of the six categories: spurting, oozing, nonbleeding visible vessel, adherent clot, flat pigmented spot, or clean based. Agreement between any two experts was expressed by a kappa estimate (kappa). Agreements over individual stigmata and a composite kappa estimate (kappa(w)) signifying overall agreement were also computed. RESULTS Out of the possible 91 pairwise kappa estimates among 14 experts, 35 (38.5%) were less than or equal to 0.40, indicating poor agreement. None of the kappa estimates was greater than 0.75. Composite kappa estimates for individual stigmata were as follows: spurting kappa = 0.664, oozing kappa = 0.420, nonbleeding visible vessel kappa = 0.342, adherent clot kappa = 0.426, flat pigmented spot kappa = 0.393, and clean-based ulcer kappa = 0.371. The weighted kappa estimate was 0.426. CONCLUSION Agreement between experts was poor in more than a third of occasions. Although the overall interobserver agreement was fair (0.4 < kappa < 0.75), agreements for nonbleeding visible vessels, flat pigmented spots, and clean-based ulcers were poor.
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120
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Kwong YL, Chan AC, Liang R, Chiang AK, Chim CS, Chan TK, Todd D, Ho FC. CD56+ NK lymphomas: clinicopathological features and prognosis. Br J Haematol 1997; 97:821-9. [PMID: 9217183 DOI: 10.1046/j.1365-2141.1997.1462962.x] [Citation(s) in RCA: 207] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The surface molecule CD56 marks a category of malignant lymphoma of putative natural killer (NK) cell origin. We conducted a retrospective analysis of 24 cases of CD56+ NK lymphoma/leukaemia to define the clinicopathologic and prognostic features of this specific group of lymphomas. 56 cases of nasal lymphomas and 204 cases with an initial diagnosis of peripheral T-cell lymphoma were retrospectively analysed. To specifically examine lymphomas of putative NK origin, only those that were negative for surface expression of CD3 but positive for CD56 were analysed. 24 cases were identified. The initial predominant sites of involvement were nasal (n = 18), palate (n = 1), nodal (n = 1) and multi-organ (n = 4). Clinically, in patients with disease localized to one anatomical site (n = 20), most had symptoms confined to the nose, with a high percentage in early stage (I: 91%; IV: 9%). The marrow was not involved in any of these cases. However, patients with multi-organ involvement at presentation (n = 4) behaved differently. All presented acutely with pancytopenia, hepatosplenomegaly, and marrow infiltration with haemophagocytosis. A leukaemic phase was observed in one case. Anthracycline containing combination chemotherapy resulted in complete remission in 75% of patients with localized disease, but only in 25% with multi-organ involvement. The median survival of patients with localized disease was 12 months, compared with 2 months in the multi-organ group (P = 0.06); the disease-free survival was significantly better in the former (P < 0.01). The overall median survival of all patients was still poor at 11 months. We conclude that CD56+ NK lymphomas could be divided into two main patterns of disease presentations: localized (predominantly nasal), and multi-organ involvement. Each has different clinicopathologic and prognostic features. Conventional chemotherapy appeared ineffective for the majority of patients, and innovative treatment modalities are needed to improve outcome.
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MESH Headings
- Adolescent
- Adult
- Aged
- Antigens, Neoplasm/metabolism
- Antineoplastic Combined Chemotherapy Protocols/therapeutic use
- Biomarkers, Tumor/metabolism
- CD56 Antigen/metabolism
- Female
- Humans
- Immunophenotyping
- Killer Cells, Natural/pathology
- Lymphoma, Non-Hodgkin/diagnosis
- Lymphoma, Non-Hodgkin/drug therapy
- Lymphoma, Non-Hodgkin/radiotherapy
- Lymphoma, T-Cell, Peripheral/diagnosis
- Lymphoma, T-Cell, Peripheral/drug therapy
- Lymphoma, T-Cell, Peripheral/radiotherapy
- Male
- Middle Aged
- Nose Neoplasms/diagnosis
- Nose Neoplasms/drug therapy
- Nose Neoplasms/radiotherapy
- Retrospective Studies
- Treatment Outcome
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Chung SS, Lau JY, Sung JJ, Chan AC, Lai CW, Ng EK, Chan FK, Yung MY, Li AK. Randomised comparison between adrenaline injection alone and adrenaline injection plus heat probe treatment for actively bleeding ulcers. BMJ (CLINICAL RESEARCH ED.) 1997; 314:1307-11. [PMID: 9158465 PMCID: PMC2126544 DOI: 10.1136/bmj.314.7090.1307] [Citation(s) in RCA: 169] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To compare endoscopic adrenaline injection alone and adrenaline injection plus heat probe for the treatment of actively bleeding peptic ulcers. DESIGN Randomised prospective study of patients admitted with actively bleeding peptic ulcers. SETTING One university hospital. SUBJECTS 276 patients with actively bleeding ulcers detected by endoscopy within 24 hours of admission: 136 patients were randomised to endoscopic adrenaline injection alone and 140 to adrenaline injection plus heat probe treatment. MAIN OUTCOME MEASURES Initial endoscopic haemostasis; clinical rebleeding; requirement for operation; requirement for blood transfusion; hospital stay, ulcer healing at four weeks; and mortality in hospital. RESULTS Initial haemostasis was achieved in 131/134 patients (98%) who received adrenaline injection alone and 135/136 patients (99%) who received additional heat probe treatment (P = 0.33). Outcome as measured by clinical rebleeding (12 v 5), requirement for emergency operation (14 v 8), blood transfusion (2 v 3 units), hospital stay (4 v 4 days), ulcer healing at four weeks (79.1% v 74%), and in hospital mortality (7 v 8) were not significantly different in the two groups. In the subgroup of patients with spurting haemorrhage 8/27 (29.6%; 14.5% to 50.3%) patients from the adrenaline injection alone group and 2/31 (6.5%; 1.1% to 22.9%) patients from the dual treatment group required operative intervention. The relative risk of this was lower in the dual treatment group (0.17; 0.03 to 0.87). Hospital stay was significantly shorter in the dual treatment group than the adrenaline injection alone group (4 v 6 days, P = 0.01). CONCLUSION The addition of heat probe treatment after endoscopic adrenaline injection confers an advantage in ulcers with spurting haemorrhage.
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Chan AC, Chung SC, Yim AP, Lau JY, Ng EK, Li AK. Comparison of two-dimensional vs three-dimensional camera systems in laparoscopic surgery. Surg Endosc 1997; 11:438-40. [PMID: 9153170 DOI: 10.1007/s004649900385] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND The lack of depth perception and spatial orientation in video vision are the drawbacks of laparoscopic surgery. The advent of a three-dimensional camera system enables surgeons to regain binocular vision and may be advantageous in complex laparoscopic procedures. METHODS We prospectively studied two groups of surgeons (with and without experiences in laparoscopic surgery) who performed a designated standardized laparoscopic task using a two-dimensional camera system (Olympus OTV-S4) vs a three-dimensional camera system (Baxter-V. Mueller VS7700) and compared their time performances. RESULTS The results suggested that only experience in laparoscopic surgery had significant effect on individual's performance. We could not demonstrate any superiority of the 3D system over the 2D system. However, two-thirds of the surgeons commented that the depth perception did improve. CONCLUSIONS With further refinement of the technology, the 3D system may improve its potential in laparoscopic surgery.
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Abstract
Malignancies arising from cells of putative natural killer (NK) cell origin have increasingly been recognized as distinct clinicopathological entities. These malignancies are marked by tumour cells with NK cell characteristics, including the immunophenotype of CD2+, surface CD3-, cytoplasmic CD3 epsilon+, CD7 +/-, and CD56+, and the genotype of germline T cell receptor gene. A consistent association with monoclonal Epstein-Barr virus infection in the tumour cell has been observed. These tumours are now regarded as putative NK cell lymphoma/leukemia. Pathologically, tumour cells show variable cytological appearances, with frequent angiocentricity and angioinvasion, associated with zonal necrosis. Clinically, most cases occur in the nasal area and upper aerodigestive tract. However, occurrence in non-nasal sites such as the skin, gastrointestinal tract and testis is also observed. A particularly aggressive form of NK lymphoma/leukemia presents fulminantly as disseminated disease sometimes with a leukemic phase. All types of NK lymphoma/leukemia have an extremely poor prognosis with a median survival of less than a year. New modalities of treatment, including the use of high dose chemotherapy and stem cell rescue may be needed to improve treatment outcome.
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Kwong YL, Chan AC, Chan TK. Widespread skin-limited Langerhans cell histiocytosis: complete remission with interferon alfa. J Am Acad Dermatol 1997; 36:628-9. [PMID: 9092752 DOI: 10.1016/s0190-9622(97)70254-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Kwong YL, Chan AC. Absence of Kaposi's sarcoma associated herpesvirus-like DNA sequences (KSHV) in HIV-negative multicentric Castleman's disease complicated by KSHV-positive Kaposi's sarcoma. Br J Haematol 1997; 96:881-2. [PMID: 9074443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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