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Ong DCT, Ho YM, Rudduck C, Chin K, Kuo WL, Lie DKH, Chua CLM, Tan PH, Eu KW, Seow-Choen F, Wong CY, Hong GS, Gray JW, Lee ASG. LARG at chromosome 11q23 has functional characteristics of a tumor suppressor in human breast and colorectal cancer. Oncogene 2009; 28:4189-200. [PMID: 19734946 PMCID: PMC2844776 DOI: 10.1038/onc.2009.266] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Deletion of 11q23-q24 is frequent in a diverse variety of malignancies, including breast and colorectal carcinoma, implicating the presence of a tumor suppressor gene at that chromosomal region. We examined a 6-Mb region on 11q23 by high-resolution deletion mapping, using both loss of heterozygosity analysis and customized microarray comparative genomic hybridization. LARG (leukemia-associated Rho guanine-nucleotide exchange factor) (also called ARHGEF12), identified from the analysed region, is frequently underexpressed in breast and colorectal carcinomas with a reduced expression observed in all breast cancer cell lines (n=11), in 12 of 38 (32%) primary breast cancers, 5 of 10 (50%) colorectal cell lines and in 20 of 37 (54%) primary colorectal cancers. Underexpression of the LARG transcript was significantly associated with genomic loss (P=0.00334). Hypermethylation of the LARG promoter was not detected in either breast or colorectal cancer, and treatment of four breast and four colorectal cancer cell lines with 5-aza-2'-deoxycytidine and/or trichostatin A did not result in a reactivation of LARG. Enforced expression of LARG in breast and colorectal cancer cells by stable transfection resulted in reduced cell proliferation and colony formation, as well as in a markedly slower cell migration rate in colorectal cancer cells, providing functional evidence for LARG as a candidate tumor suppressor gene.
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Tse GM, Tan PH, Moriya T. The role of immunohistochemistry in the differential diagnosis of papillary lesions of the breast. J Clin Pathol 2009; 62:407-13. [DOI: 10.1136/jcp.2008.063016] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Papillary lesions of the breast represent a heterogeneous group with differing biological behaviour. Correct diagnosis is crucial but may be difficult, as many benign and malignant papillary lesions have similar appearances. Immunohistochemistry plays a useful role in their differentiation. Myoepithelial markers can help in differentiating papilloma from papillary carcinoma, as the former usually shows a continuous layer of myoepithelial cells. In intracystic papillary carcinoma, there is controversy as to the presence of a complete myoepithelial cell layer around these lesions. p63 is the marker of choice as the staining is nuclear, cross-reactivity is minimal, and sensitivity is high. Papilloma may frequently be complicated by superimposed different types of epithelial hyperplasia, which range from usual to atypical or even ductal carcinoma in situ, and they many be morphologically similar. Basal cytokeratins (CKs) are useful to differentiate these entities; as usual hyperplasia is positive for basal CKs with a mosaic staining pattern. CK5/6 is probably the best marker. Neuroendocrine markers (chromogranin A and synaptophysin) may be positive in papillary carcinoma, particularly in the solid type, and there may be some overlap with the ductal carcinoma in situ with spindle cells or endocrine ductal carcinoma in situ. A panel of CK5/6, p63 and neuroendocrine markers can be useful in the diagnostic investigation of problematic papillary lesions of the breast. As the experience with these markers remains rather limited, it is too early to recommend basing treatment choices on these marker studies alone. Complete removal of lesion is probably still the treatment of choice.
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Law YM, Quek ST, Tan PH, Wong SLJ. Adenoid cystic carcinoma of the breast. Singapore Med J 2009; 50:e8-e11. [PMID: 19224074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Adenoid cystic carcinoma of the breast is a rare neoplasm that constitutes less than one percent of all mammary carcinomas. To date, there have been about 140 cases reported in the literature. It is a rare variant of adenocarcinoma that usually occurs in the salivary glands. In contrast to the aggressive nature of adenoid cystic carcinoma that occurs in the head and neck region, adenoid cystic carcinoma of the breast has a very favourable prognosis. Little has been published to date on its radiological features. We describe a 63-year-old woman with adenoid cystic carcinoma detected on mammography in our national breast screening programme, the radiological findings at presentation, the surgical management and a review of the literature.
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Tse GMK, Ma TKF, Lui PCW, Ng DCH, Yu AMC, Vong JSL, Niu Y, Chaiwun B, Lam WWM, Tan PH. Fine needle aspiration cytology of papillary lesions of the breast: how accurate is the diagnosis? J Clin Pathol 2008; 61:945-9. [DOI: 10.1136/jcp.2008.057489] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Tan PH, Janes SE, Handa AI, Friend PJ. More trouble ahead; is gene therapy coming of age? Expert Opin Biol Ther 2008; 8:561-7. [DOI: 10.1517/14712598.8.5.561] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Peh WCG, Koh WL, Kwek JW, Htoo MM, Tan PH. Imaging of painful solitary lesions of the sacrum. ACTA ACUST UNITED AC 2008; 51:507-15. [PMID: 17958684 DOI: 10.1111/j.1440-1673.2007.01861.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
In patients with sacral pain, the painful symptoms may be caused by a variety of bony and soft tissue lesions. Benign lesions include giant cell tumour, neurogenic tumour, insufficiency fracture, infection and giant bone island. Malignant lesions include primary bone tumours, Ewing sarcoma, plasmacytoma, lymphoma and chordoma. Soft tissue tumours adjacent to or involving the sacrum may cause painful symptoms. A multimodality approach to imaging is required for full assessment of these lesions. This pictorial essay describes a range of common solitary sacral lesions that may cause pain, with emphasis on imaging features.
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Tan PH, Wee KP, Sahelangi P. Remembering the Musi – SilkAir Flight MI 185 Crash Victim Identification. ANNALS OF THE ACADEMY OF MEDICINE, SINGAPORE 2007. [DOI: 10.47102/annals-acadmedsg.v36n10p861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
On 19 December 1997, SilkAir Flight MI 185, a Boeing B737-300 airliner crashed into the Musi River near Palembang, Southern Sumatra, enroute from Jakarta, Indonesia to Singapore. All 104 passengers and crew onboard were killed. Of the human remains recovered, 6 positive identifications were made, including that of one Singaporean. Two of the identifications were by dental records, 2 by fingerprints, 1 by age estimation and 1 by personal effects. This paper describes the crash victim identification of Flight MI 185. The authors were part of an Indonesia-Singapore forensic team deployed for 3 weeks in Palembang to assist the Indonesian authorities in human remains identification.
Key words: Boeing 737, Dental radiology, Disaster victim identification, Forensic odontology
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Tan PH, Wee KP, Sahelangi P. Remembering the Musi - SilkAir Flight MI 185 crash victim identification. ANNALS OF THE ACADEMY OF MEDICINE, SINGAPORE 2007; 36:861-866. [PMID: 17987240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
On 19 December 1997, SilkAir Flight MI 185, a Boeing B737-300 airliner crashed into the Musi River near Palembang, Southern Sumatra, enroute from Jakarta, Indonesia to Singapore. All 104 passengers and crew onboard were killed. Of the human remains recovered, 6 positive identifications were made, including that of one Singaporean. Two of the identifications were by dental records, 2 by fingerprints, 1 by age estimation and 1 by personal effects. This paper describes the crash victim identification of Flight MI 185. The authors were part of an Indonesia- Singapore forensic team deployed for 3 weeks in Palembang to assist the Indonesian authorities in human remains identification.
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Tan PH, Rozhin AG, Hasan T, Hu P, Scardaci V, Milne WI, Ferrari AC. Photoluminescence spectroscopy of carbon nanotube bundles: evidence for exciton energy transfer. PHYSICAL REVIEW LETTERS 2007; 99:137402. [PMID: 17930635 DOI: 10.1103/physrevlett.99.137402] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2007] [Indexed: 05/25/2023]
Abstract
We investigate photoluminescence of nanotube bundles. Their spectra are explained by exciton energy transfer between adjacent tubes, whereby excitation of large gap tubes induces emission from smaller gap ones. The consequent relaxation rate is faster than nonradiative recombination, leading to enhanced photoluminescence of acceptor tubes.
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Abstract
Breast lesions with mucin represent a broad spectrum of entities, ranging from benign fibrocystic changes with luminal mucin to mucocele-like lesions (MLL), which can be associated with banal epithelial alterations, atypical ductal hyperplasia or ductal carcinoma in situ. Occasionally invasive mucinous carcinoma can be identified in contiguity with MLL. Diagnostic challenges are enumerated, histological differentials are discussed, and a practical approach towards resolving some of these issues is provided. In addition to these lesions with abundant extracellular mucin, there are also conditions that feature stromal mucinous or myxoid material, as well as rare entities that demonstrate both epithelial extracellular and stromal mucin.
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Lian D, Cheah E, Tan PH, Thng CH, Tan SM. Phyllodes tumour with intraductal growth: a rare cause of nipple discharge. Histopathology 2007; 50:666-9. [PMID: 17394506 DOI: 10.1111/j.1365-2559.2007.02627.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Wu JI, Lo Y, Chia YY, Liu K, Fong WP, Yang LC, Tan PH. Prevention of postoperative nausea and vomiting after intrathecal morphine for Cesarean section: a randomized comparison of dexamethasone, droperidol, and a combination. Int J Obstet Anesth 2007; 16:122-7. [PMID: 17275282 DOI: 10.1016/j.ijoa.2006.11.004] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2006] [Accepted: 11/01/2006] [Indexed: 12/11/2022]
Abstract
BACKGROUND Intrathecal morphine provides good analgesia after cesarean delivery but the side effects include nausea and vomiting. Low-dose droperidol (0.625 mg) combined with dexamethasone 4 mg is postulated to have an additive antiemetic effect with less side effects. We therefore compared single doses of dexamethasone and droperidol alone with a low-dose combination of the two, to prevent spinal morphine-induced nausea and vomiting after cesarean section. METHODS In a double-blind study, 120 women undergoing elective cesarean section under spinal anesthesia (using 0.5% bupivacaine 10 mg and morphine 0.2 mg) were allocated randomly to receive dexamethasone 8 mg, droperidol 1.25 mg, dexamethasone 4 mg and droperidol 0.625 mg, or placebo, before the end of surgery. The incidences of nausea and vomiting, sedative score, pain score, and side effects were recorded. RESULTS The incidence of nausea and vomiting within 6 h postoperatively was lower and incidence of no nausea and vomiting for 24 h postoperatively was significantly higher for the combination group compared to the placebo group and the dexamethasone only group. Sedation scores within 3 h postoperatively and incidence of restlessness for the combination group were significantly lower than in the droperidol only group. CONCLUSION An additive antiemetic effect and no significant side effects were shown for the combination of dexamethasone 4 mg and droperidol 0.625 mg. This combination was more effective than either dexamethasone 8 mg or droperidol 1.25 mg alone in preventing nausea and vomiting after spinal anesthesia using 0.5% bupivacaine and morphine 0.2 mg.
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Ho BCS, Tan HW, Lee VKM, Tan PH. Preoperative and intraoperative diagnosis of low-grade adenosquamous carcinoma of the breast: potential diagnostic pitfalls. Histopathology 2007; 49:603-11. [PMID: 17163845 DOI: 10.1111/j.1365-2559.2006.02524.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
AIMS Low-grade adenosquamous carcinoma (LGAC), a rare variant of metaplastic breast cancer, may mimic benign or other low-grade malignant lesions histologically. Diagnostic difficulty may be encountered when evaluating breast cytology, core needle biopsy or intraoperative frozen section specimens. METHODS AND RESULTS Pathology reports, cytology aspirates and histological slides of LGAC diagnosed at the Department of Pathology, Singapore General Hospital, were reviewed. Four cases of LGAC were analysed. Cytology from the first case showed atypical cells and the subsequent surgical excision specimen showed a complex sclerosing lesion with LGAC. The second and third cases were investigated by core needle biopsies: the preoperative histological features were suggestive of but not diagnostic of LGAC, until further excision biopsies were performed. The fourth case entailed a frozen section specimen, for which definitive diagnosis was deferred to paraffins. The patients remained well with no evidence of recurrent disease to date. CONCLUSIONS When limited material, in the form of needle aspirates, core biopsy specimens or frozen sections, is submitted for histology, making a diagnosis of LGAC is not only challenging, but may be impossible. In difficult cases, careful pathological assessment, clinicopathological correlation and follow-up or complete excision biopsy may prove invaluable in establishing a definitive diagnosis.
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Tan PH, Giles K, Tan PL. The Transplantation Society--new key opinion leaders of tomorrow 2006. Expert Opin Biol Ther 2006; 7:149-52. [PMID: 17150026 DOI: 10.1517/14712598.7.1.149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
One of the new initiatives taken by the immediate past president of The Transplantation Society, KJ Wood, is to introduce a new series of meetings named 'New Key Opinion Leaders of Tomorrow'. The Transplantation Society invites the leading young investigators in the field of transplantation to participate in this meeting together with the present leaders of the field. The key objective of this meeting is to identify the potential key opinion leaders of tomorrow. Each presentation during the meeting was jointly given by the senior and junior investigators. The meeting in Buenos Aires covered six main topics on clinical, translational and basic transplantation. These included: innate immunity and inflammation; transplant infectious diseases; tumour and transplantation; medical and ethical aspects of transplantation; dendritic cells (stimulating and manipulating the immune response to a transplant); and ABO incompatible donor recipient pairs. This report focuses on the emerging biological therapeutics and their ramifications on clinical transplantation.
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Chew I, Tan Y, Tan PH. Cytology is useful in breast screening: results and long-term follow-up of the Singapore Breast Screening Pilot Project. Cytopathology 2006; 17:227-32. [PMID: 16961649 DOI: 10.1111/j.1365-2303.2006.00328.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE The Singapore Breast Screening Pilot Project (SBSPP) was embarked upon (1994-1997) to determine if mammography was useful in early breast cancer detection among Asian women. PATIENTS AND MEASUREMENTS Of 28 231 women screened, fine needle aspiration cytology (FNAC) was performed in 232 individuals as part of the triple assessment. RESULTS Absolute and complete sensitivities for the diagnosis of carcinoma were 46.7% and 82.2%, respectively, based on the results of FNAC. Specificity was 63.3%. The inadequate rate was 31%. Five women who were considered cancer-free on triple assessment and, in two cases open diagnostic biopsy during the SBSPP, subsequently developed breast cancer after a median follow-up of 6 years. CONCLUSION Although our FNAC results compared relatively well with international standards, they reflect a small cohort, and may face additional difficulties in a larger programme.
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Tan PH. World Transplant Congress. Boston, Massachusetts, USA, 22-27 July 2006. Expert Opin Biol Ther 2006; 6:1061-5. [PMID: 16989588 DOI: 10.1517/14712598.6.10.1061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The World Transplant Congress (WTC) is the first joint international transplant meeting co-organised by the Transplantation Society, the American Society of Transplantation (AST) and the American Society of Transplant Surgeons (ASTS). It was the first meeting of this calibre that was being held by three world-renowned authorities in the field of transplantation. Under the direction of the congress president, AB Cosimi, the attendance of this meeting is a 'must' for all working in the field of transplantation. The congress had provided an important forum for the exchange of new scientific and clinical information that is relevant to solid organ and tissue transplantation. In addition, it also created an arena for the interchange of ideas regarding the care and management of transplant recipients. There were many sessions that were engineered in order to facilitate the discussion of socioeconomic, ethical and regulatory issues related transplantation. On the whole, the meeting has set a very high standard for any future transplant congresses to match-providing the delegates with updates on transplantation with the new scientific prospectives in T cell costimulation, innate immunity (dendritic cells), anatomy of immune response and regulatory T cell biology. More importantly, it has highlighted the potentials of harnessing these new findings for future biological therapies in preventing rejection and inducing tolerance.
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Buckland M, Jago CB, Fazekasova H, Scott K, Tan PH, George AJT, Lechler R, Lombardi G. Aspirin-treated human DCs up-regulate ILT-3 and induce hyporesponsiveness and regulatory activity in responder T cells. Am J Transplant 2006; 6:2046-59. [PMID: 16869801 DOI: 10.1111/j.1600-6143.2006.01450.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Mature dendritic cells (mDCs) are potent antigen presenting cells, but immature DCs (iDCs) have been shown to have reduced antigen stimulatory capacity. Different strategies have been investigated to augment the tolerogenic capacity of dendritic cells (DCs). We demonstrate that in aspirin-treated human DCs, there is reduced expression of CD1a, HLA-DR and CD86, up-regulation of ILT-3 expression and marginal increases in PDL-1. Aspirin-treated DCs are partially resistant to phenotypic changes following maturational stimuli, such as lipopolysaccharide (LPS) or TNFalpha, IL-1alpha and PGE2. Aspirin-treated DCs demonstrate normal endocytic function, but have a reduced ability to stimulate allogeneic T cells, which is comparable to iDCs. Furthermore, they induce hyporesponsiveness and regulatory activity in responder naïve and memory T cells; for naïve T cells this is achieved more quickly and efficiently than with iDCs. We investigated the mechanism of this regulatory activity and found that both cell-cell contact and inhibitory cytokine activity are involved, although no one cytokine predominates in importance. Blocking ILT-3 or IL-12 does not diminish the capacity of these DCs to induce regulation or Foxp3 expression on the regulatory T cells. Results demonstrate that aspirin-treated DCs display tolerogenic potential, which is of interest in their therapeutic potential in reducing chronic allograft rejection.
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Abstract
The American Society of Gene Therapy, under the presidency of Mark Kay, held its annual meeting in Baltimore, MD, USA this year. This meeting was well received by academics and industry alike in order to promote research, development and application of gene therapy. Exchange of information, promotion of education and development of clinical translation have been the main aims of this society. On face value, the meeting seems to highlight that gene-based treatment is coming of age. Many drawbacks of gene-based treatments were discussed at this meeting with an intense vigour. Immunology has been the major hurdle in restricting the full realisation of gene therapy in the clinical arena. In summary, the field of gene therapy has progressed from its infancy stage of trying to get it to work, to another stage where attempts are being made to overcome the problems associated with its application, in particular, in relation to human immune responses to the vector and the transgene. This progress should be celebrated and not treated as a failure of this form of therapy, as to make this progress is indeed an achievement for any form of therapy.
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Ong CK, Leong C, Tan PH, Van T, Huynh H. The role of 5′ untranslated region in translational suppression of OKL38 mRNA in hepatocellular carcinoma. Oncogene 2006; 26:1155-65. [PMID: 16924236 DOI: 10.1038/sj.onc.1209896] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide. OKL38 is a pregnancy-induced growth inhibitory gene and its expression is lost in various breast cancer cell lines and kidney tumor. To determine the role of OKL38 expression in HCC, we investigated its expression in various HCC samples and liver cancer cell lines. Western blot analysis revealed that OKL38 protein was absent or reduced in 64.2% (18 of 28) of the HCCs examined and four liver cancer cell lines. Immunohistochemistry study demonstrated that OKL38 protein was undetectable in 41.3% (38 of 92) of HCC, whereas 39.1% (36 of 92) of HCC showed low expression of the protein. Lost or reduced expression level of OKL38 protein was significantly correlated to high tumor stages in HCC (P=0.0042). Overexpression of the OKL38 caused cell death in Chang liver cells. 5' Untranslated region (5'UTR) deletion studies demonstrated that OKL38 was downregulated via translation suppression associated with the 5'UTR of its mRNA. Taken together, the 5'UTRs of OKL38 might play an important role in downregulation of its protein and the absence of OKL38 could lead to the development or progression of HCC.
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Ho H, Chen YD, Tan PH, Wang M, Lau WKO, Cheng C. Inverted papilloma of urinary bladder: Is long-term cystoscopic surveillance needed? A single center’s experience. Urology 2006; 68:333-6. [PMID: 16904447 DOI: 10.1016/j.urology.2006.03.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2005] [Revised: 01/20/2006] [Accepted: 03/08/2006] [Indexed: 10/24/2022]
Abstract
OBJECTIVES To review all cases of urinary bladder inverted papilloma (IP) in our institution and determine the need for cystoscopic surveillance. IP is an uncommon benign tumor of the urinary tract. Its multiplicity, recurrence, and association with transitional cell carcinoma (TCC) suggest possible malignant potential, leading to conflicting clinical conclusions regarding the need for surveillance. METHODS All consecutive patients from January 1991 to December 2004 with IP were included in this study. A single pathologist performed the histologic review. The patients had undergone cystoscopy and ultrasound evaluation of the kidneys every 6 months. RESULTS Of the 52 patients, 45 were men and 7 were women. The average age at presentation was 58.9 +/- 11.8 years (range 30 to 79). No patient had a synchronous or previous bladder tumor. The most common complaint was macroscopic hematuria. Ten cases were incidental findings during bladder ultrasonography or cystoscopy. All were solitary tumors, most commonly found at the bladder neck. The average follow-up period was 62 +/- 23 months, with no recurrence. One case of subsequent noninvasive papillary TCC developed 15 months later. The initial histologic findings had revealed cytologic atypia, with suspicious urine cytology findings. On review, it was more compatible with TCC with an inverted pattern. CONCLUSIONS Although our cases exhibited benign biologic behavior, the presence of cytologic atypia and suspicious urine cytology require exclusion of TCC with an inverted pattern. Thus, in histologically proven solitary bladder IP with no associated TCC, cystoscopic surveillance may not be necessary.
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Tan PH, Lai LM, Carrington EV, Opaluwa AS, Ravikumar KH, Chetty N, Kaplan V, Kelley CJ, Babu ED. Fat necrosis of the breast—A review. Breast 2006; 15:313-8. [PMID: 16198567 DOI: 10.1016/j.breast.2005.07.003] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2005] [Accepted: 07/20/2005] [Indexed: 12/01/2022] Open
Abstract
Fat necrosis of the breast is a benign condition that most frequently affects peri-menopausal women. It can mimic breast cancer clinically or radiologically. In other cases it can obscure malignant lesions. The core of this review is derived from a MEDLINE database literature search from 1966-2004. Further references were from lateral search. In this paper, we review the pathogenesis and pathology clinical and radiological features of fat necrosis of the breast. The implication of fat necrosis in the management of patients with breast lump is also discussed. Fat necrosis of breast is a complex process. Therefore, a systematic review of this condition will enable surgeons, radiologists and oncologists working in the field of breast disease to understand it better and improve its management.
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Beutelspacher SC, Tan PH, McClure MO, Larkin DFP, Lechler RI, George AJT. Expression of indoleamine 2,3-dioxygenase (IDO) by endothelial cells: implications for the control of alloresponses. Am J Transplant 2006; 6:1320-30. [PMID: 16686756 DOI: 10.1111/j.1600-6143.2006.01324.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Indoleamine 2,3-dioxygenase (IDO) is an important enzyme in the regulation of immune responses; cells that express IDO can suppress T-cell responses and promote tolerance. Because of the critical role of endothelial cells in graft rejection, we have investigated the role of IDO expression by vascular endothelial cells and its consequence on immunoregulation. We compared the expression of IDO by primary human umbilical vein endothelial cells (HUVECs), human saphenous vein endothelial cells (HSVECs) and arterially derived endothelial cells using reverse transcriptase PCR, Western blotting and assays for enzymatic activity. In HUVECs IDO is upregulated by incubation with cytokines or in mycoplasma-infected cells. On the other hand HSVECs and arterially derived endothelial cells express little IDO, which is poorly upregulated upon activation (except by mycoplasma). Inhibition of IDO activity improved the ability of HUVECs to stimulate allogeneic T-cell responses. If either HUVECs or HSVECs are transfected with the gene encoding IDO, then they are incapable of stimulating allogeneic T-cell responses and induce anergy in allospecific T cells (which can also act as regulatory cells). The variable expression of IDO in different endothelial cells is important not only in understanding the role of endothelial cells in the regulation of graft rejection, but also as a potential therapeutic strategy.
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Fernandopulle SM, Hwang JSG, Kuick CH, Lui J, Tan PH, Siow WY, Wong M. Rosai-Dorfman disease of the testis: an unusual entity that mimics testicular malignancy. J Clin Pathol 2006; 59:325-7. [PMID: 16505287 PMCID: PMC1860335 DOI: 10.1136/jcp.2005.028423] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
A 47 year old Chinese man with diabetes mellitus and previously treated pulmonary tuberculosis presented with painless right testicular enlargement of 1 month's duration. He underwent an orchidectomy for presumed testicular neoplasm corroborated clinicoradiologically. Histological examination of the testicular mass revealed an inflammatory lesion comprising lymphocytes, plasma cells and sheets of pale staining histiocytes, some containing lymphocytes within their ample cytoplasm, suggestive of emperipolesis. S100 immunohistochemistry stained the histiocytes, while ultrastructural examination confirmed emperipolesis. A diagnosis of Rosai-Dorfman disease was made, an exceedingly rare testicular lesion. Clinicoradiological findings mimicked a neoplasm, while the inflammatory histological appearances with occasionally discerned multinucleated cells raised the possibility of xanthogranulomatous orchitis. Tuberculous orchitis was excluded through negative Ziehl-Neelsen stains and PCR for mycobacterium, while seminoma, which sometimes features a predominant inflammatory component obscuring neoplastic cells, was excluded by absent immunostaining for placental alkaline phosphatase and CD117.
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Tan PH, Chan CLH, George AJT. Strategies to improve non-viral vectors – potential applications in clinical transplantation. Expert Opin Biol Ther 2006; 6:619-30. [PMID: 16706608 DOI: 10.1517/14712598.6.6.619] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Prevention of acute rejection has been well controlled with immunosuppressive drugs. However, the long-term control of rejection is less satisfactory and the side effects of chronic usage of these drugs are far from acceptable. Thus, more imaginative options for therapy need to be explored. Gene therapy has potential promise in preserving allografts, preventing rejection and inducing tolerance. Despite this initial promise in many animal models, the translation of gene therapy to the clinical arena has been slow. This may be related in part to the deficiencies in vector development. Existing viral vectors are efficient at transducing allografts, but they induce inflammatory and pathogenic effects. Although the alternative non-viral systems are relatively innocuous, they are less efficient at gene delivery. This review systematically analyses the limitations of non-viral vector technology and the strategies that have been developed to overcome these limitations. Future development of non-viral vectors may have potential application in clinical transplantation.
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Tan HW, Chuah KL, Goh SGN, Yap WM, Tan PH. An unusual cause of granulomatous inflammation: eosinophilic abscess in Langerhans cell histiocytosis. J Clin Pathol 2006; 59:548-9. [PMID: 16644888 PMCID: PMC1860294 DOI: 10.1136/jcp.2005.029785] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/25/2005] [Indexed: 11/03/2022]
Abstract
Eosinophilic abscess inciting a granulomatous response has rarely been reported and appears not to have been described in the setting of a neoplasm. In this report, a case is described where a granulomatous response occurred around eosinophilic abscesses in a patient with Langerhans cell histiocytosis, an association which has not previously been documented. On histology, the excised lymph node showed the presence of eosinophilic abscess and necrosis surrounded by granulomas, which in turn were surrounded by Langerhans cells, a feature confirmed on immunohistochemistry. Although rare, this case highlights the importance of careful examination of eosinophilic abscess with granulomatous inflammation in order to exclude an underlying neoplasm.
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