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Klauber-DeMore N, Tan LK, Liberman L, Kaptain S, Fey J, Borgen P, Heerdt A, Montgomery L, Paglia M, Petrek JA, Cody HS, Van Zee KJ. Sentinel lymph node biopsy: is it indicated in patients with high-risk ductal carcinoma-in-situ and ductal carcinoma-in-situ with microinvasion? Ann Surg Oncol 2000; 7:636-42. [PMID: 11034239 DOI: 10.1007/s10434-000-0636-2] [Citation(s) in RCA: 255] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND Axillary lymph node status is the strongest prognostic indicator of survival for women with breast cancer. The purpose of this study was to determine the incidence of sentinel node metastases in patients with high-risk ductal carcinoma-in-situ (DCIS) and DCIS with microinvasion (DCISM). METHODS From November 1997 to November 1999, all patients who underwent sentinel node biopsy for high-risk DCIS (n = 76) or DCISM (n = 31) were enrolled prospectively in our database. Patients with DCIS were considered high risk and were selected for sentinel lymph node biopsy if there was concern that an invasive component would be identified in the specimen obtained during the definitive surgery. Patients underwent intraoperative mapping that used both blue dye and radionuclide. Excised sentinel nodes were serially sectioned and were examined by hematoxylin and eosin and by immunohistochemistry. RESULTS Of 76 patients with high-risk DCIS, 9 (12%) had positive sentinel nodes; 7 of 9 patients were positive for micrometastases only. Of 31 patients with DCISM, 3 (10%) had positive sentinel nodes. 2 of 3 were positive for micrometastases only. Six of nine patients with DCIS and three of three with DCISM and positive sentinel nodes had completion axillary dissection; one patient with DCIS had an additional positive node detected by conventional histological analysis. CONCLUSIONS This study documents a high incidence of lymph node micrometastases as detected by sentinel node biopsy in patients with high-risk DCIS and DCISM. Although the biological significance of breast cancer micrometastases remains unclear at this time, these findings suggest that sentinel node biopsy should be considered in patients with high-risk DCIS and DCISM.
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Tan LK, Suri R, Lim HL, Ong SK. Immunoglobulin D multiple myeloma in our hospital--a rare occurrence. Singapore Med J 2000; 41:500-3. [PMID: 11281443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Immunoglobulin (Ig) D multiple myeloma is a rare presentation, usually with an aggressive course and a poorer prognosis. It accounts for about 1-2% of newly diagnosed mulitple myeloma patients. Due to its rarity, reports on Ig D multiple myeloma are limited in the literature. We therefore present 4 cases of Ig D multiple myeloma in our hospital over a period of 8 years between 1990 to 1998. The average age of presentation of our patients was 44 years old with a female preponderance. Common presenting symptoms were appetite and weight loss and bone pain. Two patients presented with neurological symptoms and 2 with renal impairment. Three patients had an associated lambda paraproteinaemia and the fourth had a kappa paraproteinaemia. A common finding in Ig D myeloma is a small or no spike seen on serum electrophoresis together with heavy Bence Jones proteinuria. A review of the literature on Ig D myeloma is also presented.
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Weiser MR, Montgomery LL, Susnik B, Tan LK, Borgen PI, Cody HS. Is routine intraoperative frozen-section examination of sentinel lymph nodes in breast cancer worthwhile? Ann Surg Oncol 2000; 7:651-5. [PMID: 11034241 DOI: 10.1007/s10434-000-0651-3] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Routine intraoperative frozen section (FS) of sentinel lymph nodes (SLN) can detect metastatic disease, allowing immediate axillary dissection and avoiding the need for reoperation. Routine FS is also costly, increases operative time, and is subject to false-negative results. We examined the benefit of routine intraoperative FS among the first 1000 patients at Memorial Sloan Kettering Cancer Center who had SLN biopsy for breast cancer. METHODS We performed SLN biopsy with intraoperative FS in 890 consecutive breast cancer patients, none of whom had a back-up axillary dissection planned in advance. Serial sections and immunohistochemical staining for cytokeratins were performed on all SLN that proved negative on FS. The sensitivity of FS was determined as a function of (1) tumor size and (2) volume of metastatic disease in the SLN, and the benefit of FS was defined as the avoidance of a reoperative axillary dissection. RESULTS The sensitivity of FS ranged from 40% for patients with Tla to 76% for patients with T2 cancers. The volume of SLN metastasis was highly correlated with tumor size, and FS was far more effective in detecting macrometastatic disease (sensitivity 92%) than micrometastases (sensitivity 17%). The benefit of FS in avoiding reoperative axillary dissection ranged from 4% for Tla (6 of 143) to 38% for T2 (45 of 119) cancers. CONCLUSIONS In breast cancer patients having SLN biopsy, the failure of routine intraoperative FS is largely the failure to detect micrometastatic disease. The benefit of routine intraoperative FS increases with tumor size. Routine FS may not be indicated in patients with the smallest invasive cancers.
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Lim RL, Tan LK, Lau WF, Ming MC, Dunn R, Too HP, Chan L. Cloning and expression of immunoreactive antigens from Mycobacterium tuberculosis. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2000; 7:600-6. [PMID: 10882659 PMCID: PMC95921 DOI: 10.1128/cdli.7.4.600-606.2000] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/1999] [Accepted: 04/04/2000] [Indexed: 11/20/2022]
Abstract
Four immunoreactive proteins, B.4, B.6, B.10, and B.M, with molecular weights ranging from 16,000 to 58,000, were observed from immunoblots of Mycobacterium tuberculosis total lysates screened with sera from individuals with active tuberculosis. These proteins were identified from microsequence analyses, and genes of proteins with the highest homology were PCR amplified and cloned into the pQE30 vector for expression studies. In addition, a 37.5-kDa protein, designated C17, was identified from a phage expression library of M. tuberculosis genomic DNA. Preliminary immunoblot assays indicated that these five resultant recombinant proteins could detect antibodies in individuals with active pulmonary and extrapulmonary tuberculosis. The overall ranges of sensitivities, specificities, positive predictive values, and negative predictive values for the recombinant antigens were 20 to 58, 88 to 100, 69 to 100, and 56 to 71%, respectively. The B.6 antigen showed preferential reactivity to antibodies in pulmonary compared to nonpulmonary tuberculosis serum specimens. All of these recombinant antigens demonstrated potential for serodiagnosis of tuberculosis.
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Tan LK, Busmanis I. Spontaneous uterine perforation from uterine infarction: a rare case of acute abdomen. Aust N Z J Obstet Gynaecol 2000; 40:210-2. [PMID: 10925913 DOI: 10.1111/j.1479-828x.2000.tb01150.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
A case of spontaneous uterine perforation from uterine infarction is presented. The authors believe that this is the first reported case.
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Morris EA, Schwartz LH, Drotman MB, Kim SJ, Tan LK, Liberman L, Abramson AF, Van Zee KJ, Dershaw DD. Evaluation of pectoralis major muscle in patients with posterior breast tumors on breast MR images: early experience. Radiology 2000; 214:67-72. [PMID: 10644103 DOI: 10.1148/radiology.214.1.r00ja1667] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To evaluate the ability to use breast magnetic resonance (MR) imaging to assess disease extent in patients with posterior breast masses who are suspected to have tumor invasion into underlying muscle. MATERIALS AND METHODS Nineteen patients with posterior breast masses underwent three-dimensional, gradient-echo, 1.5-T MR imaging before and after the administration of gadopentetate dimeglumine. Thirteen had deep palpable masses that were clinically determined to be fixed to the underlying chest wall. Twelve had mammographic findings that caused muscle involvement to be suspected, and seven had normal mammograms. All patients underwent surgery. MR images were reviewed and were correlated with histologic findings. RESULTS Enhancing masses were identified on MR images in all 19 patients. Five (26%) of the 19 patients had masses that abutted the muscles, with obliteration of the fat plane and muscle enhancement. All five had muscle involvement at surgery. In the remaining 14 (74%) patients, no enhancement of muscle was seen; none of these had invasion of the muscle at surgery. CONCLUSION Extension of adjacent tumor into underlying musculature was indicated by abnormal enhancement within these structures. Violation of the fat plane between tumor and muscle, without other findings, did not indicate tumor involvement of these deep structures.
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Lee KH, Tan LK, Krishnan P, Tan KC. Successful living related liver transplantation from a donor with von Willebrand's disease. LIVER TRANSPLANTATION AND SURGERY : OFFICIAL PUBLICATION OF THE AMERICAN ASSOCIATION FOR THE STUDY OF LIVER DISEASES AND THE INTERNATIONAL LIVER TRANSPLANTATION SOCIETY 1999; 5:532-3. [PMID: 10545543 DOI: 10.1002/lt.500050609] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We report a successful living related liver transplantation from a donor with von Willebrand's disease. With proper preparation, a substantial liver resection can be performed safely in such patients, and the transplanted liver will function normally.
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Tan LK. Tonsillectomy--current practice and audit. Singapore Med J 1999; 40:618-9. [PMID: 10741186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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Tan LK, Tay SK. Two dosing regimens for preinduction cervical priming with intravaginal dinoprostone pessary: a randomised clinical trial. BRITISH JOURNAL OF OBSTETRICS AND GYNAECOLOGY 1999; 106:907-12. [PMID: 10492100 DOI: 10.1111/j.1471-0528.1999.tb08428.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To compare the efficacy within 24 hours of a three-times-a-day intensive dosing regimen with a standard once daily dosing regimen using dinoprostone vaginal pessary in preinduction cervical priming. DESIGN Randomised controlled trial. SETTING Department of Obstetrics and Gynaecology, Singapore General Hospital. PARTICIPANTS One hundred singleton term primigravidae with cephalic presentation with unfavourable cervical scores (Bishop score < or = 5) requiring induction of labour. METHODS Eligible women were randomly assigned the standard regimen (3000 microg dinoprostone [Prostin, Upjohn, Crawley, UK] once daily) or an intensive regimen (3000 microg dinoprostone given sequentially three times daily four hours apart) for cervical priming until successful priming (Bishop score of > or = 6) or the onset of active labour occurred. MAIN OUTCOME MEASURES Number of women whose cervices were ripened successfully or who entered active labour within 24 hours of starting cervical priming, priming to induction interval, and priming to delivery interval. RESULTS Forty-nine women were assigned to the standard regimen and 51 to the intensive regimen. The median number (range) of dinoprostone pessaries used was two (one to seven) in the standard regimen and three (one to nine) in the intensive regimen. Forty-two women (82.4%) who underwent the intensive regimen achieved successful cervical ripening or active labour within 24 hours, compared with 21 assigned to standard regimen (OR 6.2, 95% CI 2.3-17.4). This difference was statistically significant. The median intervals from priming to induction, and from priming to delivery, were also statistically significantly shorter in women treated with the intensive regimen. Thirty-five women (68.63%) assigned the intensive regimen experienced pain, compared with 21 (42.86%) in the standard regimen (OR 2.92, 95% CI 1.19-7.21), with two and one women in the respective regimens requiring opiate analgesics. Five women with oligohydramnios had transient cardiotocographic abnormalities during priming with the intensive regimen, none of which required immediate intervention, and the babies were born in good condition. There were no cases of uterine hypertonus and the outcomes of labour were similar for women from both regimens. CONCLUSIONS Preinduction cervical priming with the intensive dosing regimen improves the chances of successful ripening within 24 hours for primigravidae with unfavourable cervical scores at full term singleton pregnancies, and shortens the interval from priming to induction, and priming to delivery. This regimen may be more cost effective by shortening the period of hospital stay. The overall incidence of adverse reactions to the mother and fetus during priming was low. However, close fetal surveillance must be maintained, particularly in pregnancies complicated with oligohydramnios.
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Mann GB, Port ER, Rizza C, Tan LK, Borgen PI, Van Zee KJ. Six-year follow-up of patients with microinvasive, T1a, and T1b breast carcinoma. Ann Surg Oncol 1999; 6:591-8. [PMID: 10493629 DOI: 10.1007/s10434-999-0591-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Management of patients with breast cancers < or = 1 cm remains controversial. Reports of infrequent nodal metastases in tumors < or = 5 mm has led to suggestions that axillary dissection should be selective, and that tumor characteristics should guide adjuvant therapy. METHODS A retrospective review of 290 patients with breast cancer 1 cm in size or smaller from 1989 to 1991 was done. Distant disease-free survival (DDFS) was the primary outcome measure. RESULTS There were 95 T1a (< or = 5 mm) and 196 T1b (6-10 mm) cancers. Nodal metastases were found in 8 T1a and 26 T1b tumors. Larger size, poorer differentiation, and lymphovascular invasion (LVI) were associated with more nodal metastases, but none of these trends reached statistical significance. The 6-year DDFS was 93% for node-negative and 87% for node-positive patients (P = .02). Overall, breast cancers with poorer differentiation and LVI trended toward a poorer outcome. For patients with node-negative tumors, LVI was associated with a poorer outcome (P = .03). The size of the primary tumor was not predictive of outcome. There were no nodal metastases or recurrences in the 18 patients with microinvasive breast cancer. CONCLUSIONS Lymph node status is the major determinant of outcome in breast cancers 1 cm in size or smaller. Accurate axillary assessment remains crucial in management of small breast cancer.
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Tercel M, Gieseg MA, Milbank JB, Boyd M, Fan JY, Tan LK, Wilson WR, Denny WA. Cytotoxicity and DNA interaction of the enantiomers of 6-amino-3-(chloromethyl)-1-[(5,6,7-trimethoxyindol-2-yl)carbonyl]indo- line (amino-seco-CI-TMI). Chem Res Toxicol 1999; 12:700-6. [PMID: 10458703 DOI: 10.1021/tx990069o] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The enantiomers of the previously reported racemic 6-amino-3-(chloromethyl)-1-[(5,6,7-trimethoxyindol-2-yl)carbonyl] indoline (amino-seco-CI-TMI) were prepared via resolution of a precursor by chiral HPLC. The only detectable product isolated from reaction of the racemic compound with calf thymus DNA, followed by thermal cleavage, was shown by mass spectrometry and two-dimensional NMR spectroscopy to be the adenine N3 adduct. Polyacrylamide gel electrophoresis assays with the racemate and with each enantiomer also showed adenine to be the only site of alkylation. While the racemic amino compound exhibited sequence selectivity identical to that of the previously characterized phenol analogue, the enantiomers exhibited distinctly different sequence selectivities, allowing the (+) enantiomer to be assigned the "natural" S configuration. The (+)-(S) enantiomer is 3-fold more cytotoxic than the (-)-(R) enantiomer (IC(50) values of 240 and 700 nM, respectively, in AA8 cells, after exposure for 4 h).
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Busam KJ, Tan LK, Granter SR, Kohler S, Junkins-Hopkins J, Berwick M, Rosen PP. Epidermal growth factor, estrogen, and progesterone receptor expression in primary sweat gland carcinomas and primary and metastatic mammary carcinomas. Mod Pathol 1999; 12:786-93. [PMID: 10463481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
The distinction between primary sweat gland carcinomas and metastatic breast carcinoma to the skin is sometimes difficult. In an effort to improve this discrimination, we compared the immunohistochemical staining pattern of 42 primary sweat gland carcinomas (SGCs) with 30 metastases from breast carcinoma (BC) to the skin, 125 primary BCs, and 30 noncutaneous metastases from BCs. The antibodies used were against the receptors for epidermal growth factor (EGF-R), estrogen receptor (ER), and progesterone receptor (PR). The frequencies of positive staining were as follows for EGF-R: 34 (81%) of 42 SGCs, 5 (17%) of 30 BCs metastatic to skin, 28 (22%) of 125 primary BCs, and 6 (20%) of 30 noncutaneous BC metastases. For ER, the frequencies were 9 (21%) of 42 SGCs and 10 (33%) of 30 BCs metastatic to skin. The frequencies for PR were 8 (19%) of 42 SGCs and 8 (27%) of 30 BCs metastatic to skin. These results suggest that expression of EGF-R may be diagnostically helpful, because it is strongly associated with SGCs when compared with metastatic BCs (P < .0001). This association is also present when ductal eccrine and apocrine types of SGC, which are the histologic subtypes of SGC most difficult to distinguish from metastatic BC, are separately analyzed (P < .001). The frequencies of expression of ER and PR in SGCs and BCs metastatic to skin were not significantly different.
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Tan LK. Chloramphenicol-induced aplastic anaemia--should its topical use be abandoned? Singapore Med J 1999; 40:445-6. [PMID: 10560268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
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Teo MS, Tan LK, Lim TK. Lymphangiomyomatosis: radiological and measured lung function deterioration after contrast-enhanced computed tomography. AUSTRALASIAN RADIOLOGY 1999; 43:249-52. [PMID: 10901911 DOI: 10.1046/j.1440-1673.1999.00642.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Pulmonary lymphangiomyomatosis (LAM) is a rare disease of unknown aetiology which occurs exclusively in women, usually of reproductive age. The findings on CT and high-resolution CT (HRCT) are well described and characteristic, and in a young woman they are virtually pathognomonic. A case of symptomatic, radiological and measured lung function deterioration following contrast-enhanced CT in a patient with LAM are reported here. These observations, to the authors' knowledge, have never been reported before. The authors attempt to explain these observations based on the known pathology of LAM.
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Abstract
Epistaxis is a common clinical problem. The widespread availability of endoscopic equipment is shifting management philosophy toward targeting the bleeding point. This shift may have a significant impact on decreasing length of stay and blood transfusion rates. Advances in interventional radiology have also reduced the risk of embolization. Patient education, especially teaching first-aid measures to patients at high risk for nosebleeds, also encourages more effective use of health care resources.
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Tay SK, Tan LK. Outcome of early cervical carcinoma treated by Wertheim hysterectomy with selective postoperative radiotherapy. ANNALS OF THE ACADEMY OF MEDICINE, SINGAPORE 1998; 27:613-7. [PMID: 9919326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Seventy-five consecutive patients with histologically confirmed FIGO stage IB-IIA cervical carcinoma who underwent Wertheim hysterectomy were studied retrospectively. Poor prognostic factors were found in 42 (56%) patients in whom postoperative adjuvant pelvic irradiation was given. The overall disease-free survival rate was 78% at 5 years and 75% at 9 years. The tumour recurrence rate was 12.1% in the low-risk patients and 35.7% in the high-risk patients. Tumour recurrences occurred significantly more frequently in patients with tumours with high grade squamous cell carcinomas and adenosquamous carcinoma. No recurrences occurred in patients with adenocarcinomas. After adjuvant radiotherapy, there was no statistically significant difference in the recurrence rates between lymph node positive and negative patients (26.7% and 19.6% respectively), however extrapelvic recurrences were more common in those with diseased lymph nodes. The recurrence rate was 40% in patients with involved resection margins compared to 16.7% of patients with clear margins. The recurrence rates were similar for patients with and without tumour embolisation of vascular/lymphatic channels. Wertheim hysterectomy with postoperative pelvic irradiation for selected high-risk patients was an effective treatment for FIGO stage IB-IIA cervical carcinoma. Despite radiotherapy, the high-risk patients still experienced a high tumour recurrence rate.
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Kolquist KA, Ellisen LW, Counter CM, Meyerson M, Tan LK, Weinberg RA, Haber DA, Gerald WL. Expression of TERT in early premalignant lesions and a subset of cells in normal tissues. Nat Genet 1998; 19:182-6. [PMID: 9620778 DOI: 10.1038/554] [Citation(s) in RCA: 293] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Activation of telomerase, the enzyme that synthesizes the telomere ends of linear chromosomes, has been implicated in human cell immortalization and cancer cell pathogenesis. Enzyme activity is undetectable in most normal cells and tissues, but present in immortal cells and cancer tissues. While expression of TERC, the RNA component of telomerase, is widespread, the restricted expression pattern of TERT, the telomerase catalytic subunit gene, is correlated with telomerase activity, and its ectopic expression in telomerase-negative cells is sufficient to reconstitute telomerase activity and extend cellular lifespan. We have used in situ hybridization to study TERT expression at the single-cell level in normal tissues and in various stages of tumour progression. In normal tissues, including some that are known to be telomerase-negative, TERT mRNA was present in specific subsets of cells thought to have long-term proliferative capacity. This included mitotically inactive breast lobular epithelium in addition to some actively regenerating cells such as the stratum basale of the skin. TERT expression appeared early during tumorigenesis in vivo, beginning with early pre-invasive changes in human breast and colon tissues and increasing gradually during progression, both in the amount of TERT mRNA present within individual cells and in the number of expressing cells within a neoplastic lesion. The physiological expression of TERT within normal epithelial cells that retain proliferative potential and its presence at the earliest stages of tumorigenesis have implications for the regulation of telomerase expression and for the identification of cells that may be targets for malignant transformation.
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Port ER, Tan LK, Borgen PI, Van Zee KJ. Incidence of axillary lymph node metastases in T1a and T1b breast carcinoma. Ann Surg Oncol 1998; 5:23-7. [PMID: 9524703 DOI: 10.1007/bf02303759] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND We investigated the incidence of axillary lymph node metastases in patients with T1a (< or = 0.5 cm) and T1b (> 0.5 cm and < or = 1.0 cm) breast cancers. METHODS The charts of 2000 patients who underwent axillary lymph node dissection for breast cancer at our institution from 1989 to 1991 were reviewed. Of these, 81 patients had T1a and 166 had T1b primary breast cancers. RESULTS Among the 247 patients with T1a and T1b breast cancers, nodal metastases were present in 30 (12.1%), with a 7.4% positivity rate for patients with T1a and 14.5% positivity rate for T1b tumors. Of the 212 patients who had > or = 10 nodes dissected, 29 (13.7%) had positive nodes. Of those, 6 of 60 (10.0%) patients with T1a and 23 of 152 (15.1%) with T1b tumors had positive nodes. The presence of lymphovascular invasion (LVI) predicted a significantly higher nodal positivity rate (27.8% vs. 10.9%, p = 0.05). CONCLUSIONS Of patients with adequately evaluated axillae, 10% with T1a and 15% with T1b cancers were found to have nodal metastases. Although LVI was significantly associated with a higher risk of lymph node metastases, we could not characterize any subgroup at acceptably low risk of nodal positivity. Until a more useful prognostic indicator is discovered, axillary dissection should continue to be part of the mainstay of management for small breast cancers.
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Abstract
Although in endometrioid type endometrial carcinoma depth of invasion is a powerful predictor of extrauterine disease and survival, in serous carcinoma its importance is unclear. Recurrences and death in patients with serous tumors confined to the endometrium or an endometrial polyp have been reported. In other studies, however, the absence of myometrial invasion was correlated with a more favorable course. In an attempt to clarify this issue, we reviewed 13 completely staged, stage IA serous carcinomas with follow-up from 10 to 93 months (median 38), in which extensive histologic examination had been performed. Serous carcinoma was identified in an endometrial polyp in six cases, in an endometrial polyp and associated endometrium in four, and solely in the endometrium in three cases. No other histologic types of endometrial carcinoma were present, and there was no myometrial invasion. Multifocal serous intraepithelial carcinoma was also seen in 12 cases. Two of the patients died of disease with intraabdominal carcinomatosis at 10 and 14 months after presentation. The overall estimated survival was 83%, showing a relatively favorable prognosis. In conclusion, although the absence of histologically detected myometrial invasion may be associated with recurrences and death in serous carcinoma, an accurately assessed stage based on a careful histologic examination appears to be, at present, the most reliable predictor of survival.
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Calvano JE, Rush EB, Tan LK, Rosen PP, Borgen PI, Van Zee KJ. Absence of p16 gene (CDKN2) deletions in microdissected primary breast carcinoma specimens. Ann Surg Oncol 1997; 4:416-20. [PMID: 9259969 DOI: 10.1007/bf02305555] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND The p16 gene (CDKN2), a tumor suppressor gene located on chromosome 9p21, has been demonstrated to be mutated or deleted with high frequency in a variety of tumor cell lines, including breast. While previous studies have not demonstrated CDKN2 mutations in primary breast carcinomas, it is possible that gene deletion in neoplastic DNA was marked by the presence of contaminating normal stromal DNA in breast carcinoma specimens. METHODS We investigated the incidence of homozygous deletion of CDKN2 by analyzing 20 microdissected pure populations of primary breast carcinoma cells. Using polymerase chain reaction (PCR) techniques, the entire coding region and intervening introns of CDKN2 were amplified. The PCR products were resolved by agarose gel electrophoresis and single-strand conformation polymorphism (SSCP) analysis. RESULTS We detected no deletions or mutations of the p16 gene. CONCLUSIONS CDKN2 is not deleted with high frequency in primary breast carcinomas, and the p16 gene does not play a role in breast carcinogenesis via this mechanism.
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Tan LK, Ogden GR. p53 over-expression in laryngeal carcinoma is not predictive of response to radiotherapy. Oral Oncol 1997; 33:177-81. [PMID: 9307726 DOI: 10.1016/s0964-1955(96)00082-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
It has been suggested that alteration involving the p53 gene may influence tumour response to radiotherapy. If this were so, then p53 overexpression (which is usually associated with p53 mutation and readily detectable in routine diagnostic pathology) may help determine the most appropriate form of cancer therapy. p53 expression was assessed in 90 formalin-fixed paraffin-embedded laryngeal carcinomas that were subsequently treated with radiotherapy. The polyclonal antibody DO1 (1 in 50 dilution) was used, together with an avidin-biotin immunoperoxidase technique, but in the absence of any additional antigen retrieval techniques. p53 expression was assessed and correlated with various clinicopathological parameters. Using Chi square analysis, no significant difference between p53 positive and p53 negative lesions was found for response to radiotherapy, as measured by survival and recurrence rates. Furthermore, no correlation with p53 expression was found for tumour size, nodal metastasis, sex, age, alcohol intake, tobacco habit and histological grade. This absence of correlation may in part be explained by discrepancies between immunohistochemical detection of p53 and p53 mutation, although the lack of predictive response to radiotherapy mimics that recently found for irradiated head and neck cancer cell lines.
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White PS, Frizelle FA, Hanna GB, Tan LK, Gardiner Q, Cuschieri A. Comparison of direct monocular endoscopic, two- and three-dimensional display systems on surgical task performance in functional endoscopic sinus surgery. Clin Otolaryngol 1997; 22:65-7. [PMID: 9088684 DOI: 10.1046/j.1365-2273.1997.00868.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Surgeons performing functional endoscopic sinus surgery (FESS) traditionally rely on direct endoscopic viewing through a single monocular Hopkins rod lens telescope. While the majority of surgeons have found this satisfactory, most other endoscopic surgical specialties have moved to 2-D video endoscopy, where a monoscopic image is presented on a television monitor. This study set out to determine whether 2-D or 3-D display systems had any advantage over direct endoscopy in FESS. Ten otolaryngology trainees performed a series of standardized procedures on a FESS model using direct endoscopic vision, 2-D and 3-D. A performance score was obtained by dividing the execution time by the number of tasks achieved. There was a significant difference in both surgical and diagnostic task performance with 2-D (mean scores 56.8 and 41.1) performing better than direct endoscopy (mean scores 94.1 and 74.1) (P < 0.05). Tasks were also performed significantly better with 3-D compared with 2-D (P < 0.05).
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Abstract
In vitro studies have suggested that beta 2-adrenergic agents increase the ciliary beat frequency in human respiratory epithelium. We carried out a randomized, double-blind placebo-controlled trial to investigate the effects of a topical spray, salmeterol, on nasal mucociliary clearance using the saccharin test. Thirty-three healthy adults were recruited. There was a 21% reduction of nasal mucociliary transport time of saccharin with salmeterol compared to placebo (P = 0.0001). There was no effect of age, sex, order of treatment, interval between spray and saccharin test, or history of seasonal allergic rhinitis on the improvement in clearance times.
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74
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Abstract
PURPOSE To describe the mammographic and sonographic appearance of a pattern of spiculation of the contour of axillary lymph nodes. MATERIALS AND METHODS Eleven cases of axillary nodes with spiculated contour were prospectively identified on routine mammograms. All cases were in women with breast cancer. Sonograms of axillary nodes were available in three cases. Medical records were reviewed, and histologic and nodal histopathologic findings and patient outcome were correlated. RESULTS All women had primary, invasive breast carcinoma. Although disease was evident mammographically, four of nine women for whom the results of the physical examination were known did not have palpable adenopathy. Nodes were iso-to hyperdense (compared with breast parenchyma) on mammograms and were hypoechoic with irregular margins on sonograms. The spiculated pattern of the nodes correlated with extension of metastatic tumor in axillary nodes into perinodal fat. At a mean follow-up of 17 months, one patient was dead of disease, eight were alive with disease, and two were alive without disease. CONCLUSION A pattern of spiculated axillary adenopathy in a patient with breast cancer appears to be consistent with extranodal extension of tumor into perinodal fat. This finding suggests a biologically aggressive tumor with a poor prognosis.
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Talwar M, Moyana TN, Bharadwaj B, Tan LK. The effect of a synthetic analogue of prostaglandin E2 on wound healing in rats. ANNALS OF CLINICAL AND LABORATORY SCIENCE 1996; 26:451-7. [PMID: 8879363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
This was a prospective, randomized, double-blind experimental study to assess the effect of a long-acting prostaglandin (PG) analogue on wound healing in rats. Eight-cm long, dorsal midline skin incisions were made on rats (n = 44) and immediately resutured. The treatment group (n = 22) received daily intraperitoneal injections of 16,16-dimethyl prostaglandin E2-methyl ester (di-MPGE2) for 7 days, whereas the controls (n = 22) received normal saline. The rats were sacrificed in groups of 11 at 7 and 14 days, respectively. The wounds were excised and analyzed. Histology showed that there was increased fibrosis (p < 0.03) and a decreased number of macrophages (p < 0.02) in the PG group at 7 days. Tensile strength and hydroxyproline content also increased but did not attain significant levels. The differences between the PG and control groups at 14 days similarly did not attain statistical significance. The results suggest that in wound healing, the administration of di-MPGE2 may be beneficial during the early stages of inflammation, rather than during the later stages of remodelling.
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