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S K Chan

Publications and source records attributed to S K Chan.

85 records · Page 5Linked to original sources

Cytomegalovirus-induced tubulointerstitial nephritis in a renal allograft treated by foscarnet therapy.

We report a female patient suffering from cytomegalovirus (CMV)-induced tubulointerstitial nephritis in a renal allograft 70 days after a cadaveric renal transplantation. CMV-induced renal allograft injury reported in the literature mainly related to immune-mediated mechanisms. In our patient, acute tubulointerstitial nephritis, associated with histological evidence of CMV infection, was demonstrated in the renal allograft biopsy. There were no histological features of allograft rejection, cyclosporin nephrotoxicity nor 'CMV glomerulopathy'. She was successfully treated by foscarnet therapy and a reduction in immunosuppression. Her renal function returned to baseline afterwards.

Adult↗

Pulmonary sclerosing hemangioma. Report of a case with diagnosis by fine needle aspiration.

Sclerosing hemangioma is a rare but well-recognized benign lesion of the lung. We report a case of pulmonary sclerosing hemangioma correctly diagnosed by fine needle aspiration (FNA) cytology. The sharp and smooth contour of the discrete mass in the left lower zone of the chest roentgenogram raised the possibility of a benign lesion, including pulmonary sclerosing hemangioma. The characteristic "blood spaces" with surrounding regular, bland polygonal tumor cells in the FNA smears provided an essential clue to the diagnosis of sclerosing hemangioma. It was confirmed by Surecut biopsy of the lesion. The patient remained well one year after the investigation and was spared an unnecessary diagnostic thoracotomy. The cytologic features and differential diagnoses of pulmonary sclerosing hemangioma are discussed. Besides delineating the cytologic characteristics of pulmonary sclerosing hemangioma, this case illustrates the importance of a careful clinicopathologic correlation, which should be exercised by the cytopathologist in all instances.

Aged↗

Fine needle aspiration diagnosis of pilomatrixoma. A monomorphic population of basaloid cells with squamous differentiation not to be mistaken for carcinoma.

In a case of pilomatrixoma, an initial fine needle aspiration (FNA) biopsy of a skin lesion yielded only a monomorphic population of mitotically active basaloid cells with squamous differentiation, without anucleated ghost cells, chronic inflammatory cells or foreign-body giant cells. These findings suggested a metastatic squamous-cell carcinoma or a malignant tumor of adnexal skin. The correct diagnosis was made by repeat FNA, which yielded the basaloid cells and ghost cells characteristics of pilomatrixoma; the FNA diagnosis was confirmed by subsequent excisional biopsy. This case demonstrates that pilomatrixoma should be considered in the differential diagnosis of skin aspirates that contain a dominant population of basaloid cells. The differentiation of pilomatrixoma from malignant lesions of the head and neck region is discussed.

Biopsy, Needle↗

Application of the immunoperoxidase technique to cell block preparations from fine needle aspirates.

Immunocytochemistry on fine needle aspiration (FNA) material has been mainly performed on cytologic preparations; there have been few reports on the use of FNA cell blocks. This study compared the intensity scores of immunoperoxidase staining on FNA cell block preparations from 21 breast, 12 thyroid and 10 lymph node aspirates with the scores on the corresponding surgically excised specimens. FNA materials for cell blocks were fixed in formalin and embedded in agar. Ten commercially available antibodies forming three panels were studied using standard peroxidase-antiperoxidase and avidin-biotin complex techniques. In general, the staining results on the FNA cell block sections agreed with those on the surgical specimens; in addition, there were fewer aberrant positive staining results and much less background staining in the cell block sections. These phenomena were most striking with the cytokeratin antibodies. It is concluded that immunoperoxidase staining on FNA cell block preparations is reliable; the advantages of the use of cell block sections as opposed to smears are discussed.

Antibodies, Monoclonal↗

Fine needle aspiration cytodiagnosis of leiomyosarcoma of the renal pelvis. A case report with immunohistochemical study.

Leiomyosarcoma of the renal pelvis is extremely rare. We report one such case correctly diagnosed by ultrasound-guided fine needle aspiration cytology (FNAC). The FNAC smears showed a monotonous population of closely packed, spindled tumor cells arranged in interlacing bundles. Those cells possessed markedly pleomorphic, hyperchromatic, elongated nuclei and a moderate amount of eosinophilic, fibrillary cytoplasm. Fascicles of similar spindle tumor cells arranged in a whorled pattern were seen in the section of the cell block. Immunohistochemistry was performed on the sections of the cell block preparation, showing intensely positive cytoplasmic staining of the tumor cells for muscle-specific actin but negative staining for CAM 5.2, AE1/AE3, S-100 protein and HMB-45. This staining pattern of the tumor allows its differentiation from other primary sarcomas of the kidney, sarcomatoid renal cell carcinoma, peripheral nerve sheath tumor and renal angiomyolipoma. The extreme degree of nuclear pleomorphism and hyperchromatism is not to be expected in renal leiomyoma or the usual cases of mesoblastic nephroma. Besides delineating the FNAC features of leiomyosarcoma of the renal pelvis, the present case illustrates the value of using the cell block preparation in FNAC.

Actins↗