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Focal neuroendocrine differentiation in colorectal adenomas (microcarcinoids)
S64
PATHOLOGY 2011 ABSTRACT SUPPLEMENT
PSEUDONORMO- AND PSEUDOHYPERNATRAEMIA IN SICK NEONATES R. I. King, R. J. MacKay, C. M. Florkowski Clinical Biochemistry, Canterbury Health Laboratories, Christchurch, New Zealand Introduction: Pseudohyponatraemia is well recognised when using indirect ion selective electrodes (ISE) in samples with raised plasma protein or lipid. ‘Ion-exclusion’ may also cause pseudonormo- or pseudohypernatraemia in low protein states which are common in sick neonates. We investigated the effect of hypoalbuminaemia on sodium measured by direct and indirect ISE in neonates. Method: This retrospective study compared electrolyte results from paired samples, performed on the Abbott Architect (indirect ISE) and neonatal unit blood-gas analyser (direct ISE). Results: Of 2420 paired results, hypoalbuminaemia (<30 g/L) was present in 44%. Sodium results were higher when measured by indirect ISE and the difference between results increased with decreasing albumin concentration; sodium [indirect – direct ISE] ¼ 7.64 – 0.22 albumin, 95%CI slope –0.19 to –0.25, r ¼ 0.309, p < 0.001. The absolute difference in sodium was >3 mmol/L (the allowable limit of performance) in 31% and led to the misclassification of results as pseudonormonatraemia (9.4%) and pseudohypernatraemia (5.3%). Discussion: Hypoalbuminaemia is common in sick neonates and concurrent measurement of electrolytes using direct and indirect ISEs frequently yields significantly different results leading to misclassification. In these patients, measurement of electrolytes by direct ISE may be more accurate.
FOCAL NEUROENDOCRINE DIFFERENTIATION IN COLORECTAL ADENOMAS (MICROCARCINOIDS) Mary-Ann Koh1, Ian Brown2, Daniel James1 1 Queensland Health, Royal Brisbane and Women’s Hospital and 2 Sullivan Nicolaides Pathology, Qld, Australia Microcarcinoids are small clusters or nests of neoplastic cells showing neuroendocrine differentiation. We present four cases of microcarcinoid arising within colorectal adenomas, a rare entity that has only recently been described in one other series. Our cases have been collected from routine biopsies over the last 2 years. In each case, the microcarcinoids are seen budding from the crypt base and forming separate small nests within the lamina propria. These lesions tend not to alter the overall architecture of the adenoma and form only a small proportion of the main lesion. Their appearance is distinct from the adjacent adenomatous epithelium. The cells range from round to cuboidal with eosinophillic cytoplasm, bland appearing nuclei and fine chromatin. It is important to recognise these lesions as they present a potential diagnostic pitfall and can easily be mistaken for microinvasion. The nature of these lesions can be confirmed with positive immunohistochemical markers for neuroendocrine differentiation such as chromogranin, synaptophysin, CD56 and neuron specific enolase. Reference Pulitzer M, Xu R, Suriawinata AA, et al. Microcarcinoids in large intestinal adenomas. Am J Surg Pathol 2006; 30: 1531–6.
Pathology (2011), 43(S1)
MULTIPLE NOVEL APOPTOTIC PATHWAYS ARE UPREGULATED IN EXTRAMAMMARY PAGET’S DISEASE Fiona Lehane, Jane E. Armes, Rohan Lourie, Melissa Hillas Department of Anatomical Pathology, Mater Pathology Services, South Brisbane, Qld, Australia Aim: To investigate the expression of the novel anti-apoptotic markers GRP78 and MUC13 in extramammary Paget’s disease (EMPD). Method: Twelve archival cases of EMPD, accessioned from 2001 until 2010 were assessed for expression of bcl-2, GRP78 and MUC13 using standard immunohistochemical and immunofluorescent techniques. Results: Twelve cases of EMPD were examined, four of which included an invasive component. Eight of twelve cases (67%) were positive for bcl2. Eight of eleven cases (72%), and four of eight cases (50%) with available tissue were positive for GRP78 and MUC13, respectively. Discussion: Bcl2 is a well known regulator of apoptosis. GRP78 overexpression has been shown to significantly increase resistance to apoptosis in vitro and in vivo. MUC13 is overexpressed in a range of epithelial malignancies, and has poorly defined antiapoptotic properties, as well as a role in proliferation activity via the p38MAPK signalling pathway, and anti-adhesive roles promoting cell motility. Our study has demonstrated an overexpression of the anti-apoptotic markers GRP78, MUC13, and bcl2 in EMPD. Overexpression of these anti-apoptotic markers is a novel finding in this disease and likely to be important in the pathogenesis of EMPD. EVALUATION OF THYROGLOBULIN ASSAYED BY BECKMAN ACCESS Xunjun Low, Roger Johnson, Linda Henderson Department of Chemical Pathology, Labplus, Auckland City Hospital, Auckland, New Zealand Aims: To evaluate a thyroglobulin chemiluminescent immunoassay (CLIA) on the Access (Beckman Coulter) as a possible replacement for the thyroglobulin CLIA on Immulite 2000 (Siemens). Methods and Results: 20 patient samples (0.14–473 mg/L) assayed in duplicate on the Access had an average CV (of duplicates) of 1.0% with none greater than 6%. Immulite QC plus a low pool sample (range 0.14–129.8 mg/L) run (n ¼ 41) over 3 weeks gave interbatch imprecision (CV) of 3.1–11.7%. A comparison between Access and Immulite method (as reference) using 20 patient samples (up to 600 mg/L) gave a slope of 0.70 and negligible intercept by Passing-Bablok analysis; least squares linear regression gave similar information. 17 samples containing different proportions of thyroglobulin were found on the Access to be linear up to 450 mg/L, the highest concentration tested. Interference from lipaemia, icterus, or haemolysis showed a difference from control of –2.6 to 0.3%. Discussion: Access thyroglobulin immunoassay has good precision, is linear to at least 450 mg/L, and suffers negligible interference from haemolysis, icterus and lipaemia. The major disparity with the Immulite assay is a negative bias (equivalent to slope of about 0.7), giving an upper limit of the reference interval of 40 mg/L rather than 55 mg/L as at present.
Copyright © Royal College of pathologists of Australasia. Unauthorized reproduction of this article is prohibited.
PATHOLOGY 2011 ABSTRACT SUPPLEMENT
PSEUDONORMO- AND PSEUDOHYPERNATRAEMIA IN SICK NEONATES R. I. King, R. J. MacKay, C. M. Florkowski Clinical Biochemistry, Canterbury Health Laboratories, Christchurch, New Zealand Introduction: Pseudohyponatraemia is well recognised when using indirect ion selective electrodes (ISE) in samples with raised plasma protein or lipid. ‘Ion-exclusion’ may also cause pseudonormo- or pseudohypernatraemia in low protein states which are common in sick neonates. We investigated the effect of hypoalbuminaemia on sodium measured by direct and indirect ISE in neonates. Method: This retrospective study compared electrolyte results from paired samples, performed on the Abbott Architect (indirect ISE) and neonatal unit blood-gas analyser (direct ISE). Results: Of 2420 paired results, hypoalbuminaemia (<30 g/L) was present in 44%. Sodium results were higher when measured by indirect ISE and the difference between results increased with decreasing albumin concentration; sodium [indirect – direct ISE] ¼ 7.64 – 0.22 albumin, 95%CI slope –0.19 to –0.25, r ¼ 0.309, p < 0.001. The absolute difference in sodium was >3 mmol/L (the allowable limit of performance) in 31% and led to the misclassification of results as pseudonormonatraemia (9.4%) and pseudohypernatraemia (5.3%). Discussion: Hypoalbuminaemia is common in sick neonates and concurrent measurement of electrolytes using direct and indirect ISEs frequently yields significantly different results leading to misclassification. In these patients, measurement of electrolytes by direct ISE may be more accurate.
FOCAL NEUROENDOCRINE DIFFERENTIATION IN COLORECTAL ADENOMAS (MICROCARCINOIDS) Mary-Ann Koh1, Ian Brown2, Daniel James1 1 Queensland Health, Royal Brisbane and Women’s Hospital and 2 Sullivan Nicolaides Pathology, Qld, Australia Microcarcinoids are small clusters or nests of neoplastic cells showing neuroendocrine differentiation. We present four cases of microcarcinoid arising within colorectal adenomas, a rare entity that has only recently been described in one other series. Our cases have been collected from routine biopsies over the last 2 years. In each case, the microcarcinoids are seen budding from the crypt base and forming separate small nests within the lamina propria. These lesions tend not to alter the overall architecture of the adenoma and form only a small proportion of the main lesion. Their appearance is distinct from the adjacent adenomatous epithelium. The cells range from round to cuboidal with eosinophillic cytoplasm, bland appearing nuclei and fine chromatin. It is important to recognise these lesions as they present a potential diagnostic pitfall and can easily be mistaken for microinvasion. The nature of these lesions can be confirmed with positive immunohistochemical markers for neuroendocrine differentiation such as chromogranin, synaptophysin, CD56 and neuron specific enolase. Reference Pulitzer M, Xu R, Suriawinata AA, et al. Microcarcinoids in large intestinal adenomas. Am J Surg Pathol 2006; 30: 1531–6.
Pathology (2011), 43(S1)
MULTIPLE NOVEL APOPTOTIC PATHWAYS ARE UPREGULATED IN EXTRAMAMMARY PAGET’S DISEASE Fiona Lehane, Jane E. Armes, Rohan Lourie, Melissa Hillas Department of Anatomical Pathology, Mater Pathology Services, South Brisbane, Qld, Australia Aim: To investigate the expression of the novel anti-apoptotic markers GRP78 and MUC13 in extramammary Paget’s disease (EMPD). Method: Twelve archival cases of EMPD, accessioned from 2001 until 2010 were assessed for expression of bcl-2, GRP78 and MUC13 using standard immunohistochemical and immunofluorescent techniques. Results: Twelve cases of EMPD were examined, four of which included an invasive component. Eight of twelve cases (67%) were positive for bcl2. Eight of eleven cases (72%), and four of eight cases (50%) with available tissue were positive for GRP78 and MUC13, respectively. Discussion: Bcl2 is a well known regulator of apoptosis. GRP78 overexpression has been shown to significantly increase resistance to apoptosis in vitro and in vivo. MUC13 is overexpressed in a range of epithelial malignancies, and has poorly defined antiapoptotic properties, as well as a role in proliferation activity via the p38MAPK signalling pathway, and anti-adhesive roles promoting cell motility. Our study has demonstrated an overexpression of the anti-apoptotic markers GRP78, MUC13, and bcl2 in EMPD. Overexpression of these anti-apoptotic markers is a novel finding in this disease and likely to be important in the pathogenesis of EMPD. EVALUATION OF THYROGLOBULIN ASSAYED BY BECKMAN ACCESS Xunjun Low, Roger Johnson, Linda Henderson Department of Chemical Pathology, Labplus, Auckland City Hospital, Auckland, New Zealand Aims: To evaluate a thyroglobulin chemiluminescent immunoassay (CLIA) on the Access (Beckman Coulter) as a possible replacement for the thyroglobulin CLIA on Immulite 2000 (Siemens). Methods and Results: 20 patient samples (0.14–473 mg/L) assayed in duplicate on the Access had an average CV (of duplicates) of 1.0% with none greater than 6%. Immulite QC plus a low pool sample (range 0.14–129.8 mg/L) run (n ¼ 41) over 3 weeks gave interbatch imprecision (CV) of 3.1–11.7%. A comparison between Access and Immulite method (as reference) using 20 patient samples (up to 600 mg/L) gave a slope of 0.70 and negligible intercept by Passing-Bablok analysis; least squares linear regression gave similar information. 17 samples containing different proportions of thyroglobulin were found on the Access to be linear up to 450 mg/L, the highest concentration tested. Interference from lipaemia, icterus, or haemolysis showed a difference from control of –2.6 to 0.3%. Discussion: Access thyroglobulin immunoassay has good precision, is linear to at least 450 mg/L, and suffers negligible interference from haemolysis, icterus and lipaemia. The major disparity with the Immulite assay is a negative bias (equivalent to slope of about 0.7), giving an upper limit of the reference interval of 40 mg/L rather than 55 mg/L as at present.
Copyright © Royal College of pathologists of Australasia. Unauthorized reproduction of this article is prohibited.