Macrocalcitonin Is a Novel Pitfall in the Routine of Serum Calcitonin Immunoassay

Detalhes bibliográficos
Autor(a) principal: Alves, Thalita G. [UNIFESP]
Data de Publicação: 2016
Outros Autores: Kasamatsu, Teresa S. [UNIFESP], Yang, Ji H. [UNIFESP], Meneghetti, Maria Cecilia Z. [UNIFESP], Mendes, Aline [UNIFESP], Kunii, Ilda S. [UNIFESP], Lindsey, Susan C. [UNIFESP], Camacho, Cleber P. [UNIFESP], Dias da Silva, Magnus R. [UNIFESP], Maciel, Rui M. B. [UNIFESP], Vieira, Jose Gilberto H. [UNIFESP], Martins, Joao Roberto M. [UNIFESP]
Tipo de documento: Artigo
Idioma: eng
Título da fonte: Repositório Institucional da UNIFESP
Texto Completo: http://dx.doi.org/10.1210/jc.2015-3137
https://repositorio.unifesp.br/handle/11600/57993
Resumo: Context: Calcitonin (CT) is a sensitive marker of medullary thyroid carcinoma (MTC) and is used for primary diagnosis and follow-up after thyroidectomy. However, persistently elevated CT is observed even after complete surgical removal without evidence of a recurrent or persistent tumor. Objective: To investigate the presence of assay interference in the serum CT of MTC patients who are apparently without a structural disease. Patients and Methods: We studied three index MTC cases for CT assay interference and 14 patients with metastatic MTC. The CT level was measured using an immunofluorometric assay. Screening for assay interference was performed by determination of CT levels before and after serum treatment with polyethylene glycol. Additionally, samples were analyzed by chromatography on ultra-performance liquid chromatography and protein A-Sepharose. Results: Patients with biochemical and structural disease showed CT mean recovery of 84.1% after polyethylene glycol treatment, whereas patients suspected of interference showed recovery from 2-7%. The elution profile on UPLC showed that the immunometric CT from these three patients behaved like a high molecular mass aggregate (>300 kDa). Additionally, when these samples were applied to the protein A-Sepharose, CT immunoreactivity was retained on the column and was only released after lowering the pH. Conclusions: For the first time, our results show the presence of a novel pitfall in the CT immunoassay: "macrocalcitonin." Its etiology, frequency, and meaning remain to be defined, but its recognition is of interest and can help clinicians avoid unnecessary diagnostic investigations and treatment during the follow-up of MTC.
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spelling Macrocalcitonin Is a Novel Pitfall in the Routine of Serum Calcitonin ImmunoassayContext: Calcitonin (CT) is a sensitive marker of medullary thyroid carcinoma (MTC) and is used for primary diagnosis and follow-up after thyroidectomy. However, persistently elevated CT is observed even after complete surgical removal without evidence of a recurrent or persistent tumor. Objective: To investigate the presence of assay interference in the serum CT of MTC patients who are apparently without a structural disease. Patients and Methods: We studied three index MTC cases for CT assay interference and 14 patients with metastatic MTC. The CT level was measured using an immunofluorometric assay. Screening for assay interference was performed by determination of CT levels before and after serum treatment with polyethylene glycol. Additionally, samples were analyzed by chromatography on ultra-performance liquid chromatography and protein A-Sepharose. Results: Patients with biochemical and structural disease showed CT mean recovery of 84.1% after polyethylene glycol treatment, whereas patients suspected of interference showed recovery from 2-7%. The elution profile on UPLC showed that the immunometric CT from these three patients behaved like a high molecular mass aggregate (>300 kDa). Additionally, when these samples were applied to the protein A-Sepharose, CT immunoreactivity was retained on the column and was only released after lowering the pH. Conclusions: For the first time, our results show the presence of a novel pitfall in the CT immunoassay: "macrocalcitonin." Its etiology, frequency, and meaning remain to be defined, but its recognition is of interest and can help clinicians avoid unnecessary diagnostic investigations and treatment during the follow-up of MTC.Univ Fed Sao Paulo, Escola Paulista Med, Div Endocrinol, Dept Med,Thyroid Dis Ctr, BR-04039032 Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Escola Paulista Med, Div Endocrinol, Dept Med,Lab Mol & Translat Endocrinol, BR-04039032 Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Escola Paulista Med, Dept Biochem, Div Mol Biol, BR-04044020 Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Escola Paulista Med, Div Endocrinol, Dept Med,Thyroid Dis Ctr, BR-04039032 Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Escola Paulista Med, Div Endocrinol, Dept Med,Lab Mol & Translat Endocrinol, BR-04039032 Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Escola Paulista Med, Dept Biochem, Div Mol Biol, BR-04044020 Sao Paulo, SP, BrazilWeb of ScienceSao Paulo State Research Foundation-FAPESPFAPESPFederal Agency of Support and Evaluation of Postgraduate Education (Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior)National Council for Scientific and Technological DevelopmentFAPESP: 2006/60402-1FAPESP: 2010/51547-1FAPESP: 2010/19478Endocrine Soc2020-08-21T17:00:26Z2020-08-21T17:00:26Z2016info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersion653-658application/pdfhttp://dx.doi.org/10.1210/jc.2015-3137Journal Of Clinical Endocrinology & Metabolism. Washington, v. 101, n. 2, p. 653-658, 2016.10.1210/jc.2015-3137WOS000378642700035.pdf0021-972Xhttps://repositorio.unifesp.br/handle/11600/57993WOS:000378642700035engJournal Of Clinical Endocrinology & MetabolismWashingtoninfo:eu-repo/semantics/openAccessAlves, Thalita G. [UNIFESP]Kasamatsu, Teresa S. [UNIFESP]Yang, Ji H. [UNIFESP]Meneghetti, Maria Cecilia Z. [UNIFESP]Mendes, Aline [UNIFESP]Kunii, Ilda S. [UNIFESP]Lindsey, Susan C. [UNIFESP]Camacho, Cleber P. [UNIFESP]Dias da Silva, Magnus R. [UNIFESP]Maciel, Rui M. B. [UNIFESP]Vieira, Jose Gilberto H. [UNIFESP]Martins, Joao Roberto M. [UNIFESP]reponame:Repositório Institucional da UNIFESPinstname:Universidade Federal de São Paulo (UNIFESP)instacron:UNIFESP2024-08-09T10:57:55Zoai:repositorio.unifesp.br/:11600/57993Repositório InstitucionalPUBhttp://www.repositorio.unifesp.br/oai/requestbiblioteca.csp@unifesp.bropendoar:34652024-08-09T10:57:55Repositório Institucional da UNIFESP - Universidade Federal de São Paulo (UNIFESP)false
dc.title.none.fl_str_mv Macrocalcitonin Is a Novel Pitfall in the Routine of Serum Calcitonin Immunoassay
title Macrocalcitonin Is a Novel Pitfall in the Routine of Serum Calcitonin Immunoassay
spellingShingle Macrocalcitonin Is a Novel Pitfall in the Routine of Serum Calcitonin Immunoassay
Alves, Thalita G. [UNIFESP]
title_short Macrocalcitonin Is a Novel Pitfall in the Routine of Serum Calcitonin Immunoassay
title_full Macrocalcitonin Is a Novel Pitfall in the Routine of Serum Calcitonin Immunoassay
title_fullStr Macrocalcitonin Is a Novel Pitfall in the Routine of Serum Calcitonin Immunoassay
title_full_unstemmed Macrocalcitonin Is a Novel Pitfall in the Routine of Serum Calcitonin Immunoassay
title_sort Macrocalcitonin Is a Novel Pitfall in the Routine of Serum Calcitonin Immunoassay
author Alves, Thalita G. [UNIFESP]
author_facet Alves, Thalita G. [UNIFESP]
Kasamatsu, Teresa S. [UNIFESP]
Yang, Ji H. [UNIFESP]
Meneghetti, Maria Cecilia Z. [UNIFESP]
Mendes, Aline [UNIFESP]
Kunii, Ilda S. [UNIFESP]
Lindsey, Susan C. [UNIFESP]
Camacho, Cleber P. [UNIFESP]
Dias da Silva, Magnus R. [UNIFESP]
Maciel, Rui M. B. [UNIFESP]
Vieira, Jose Gilberto H. [UNIFESP]
Martins, Joao Roberto M. [UNIFESP]
author_role author
author2 Kasamatsu, Teresa S. [UNIFESP]
Yang, Ji H. [UNIFESP]
Meneghetti, Maria Cecilia Z. [UNIFESP]
Mendes, Aline [UNIFESP]
Kunii, Ilda S. [UNIFESP]
Lindsey, Susan C. [UNIFESP]
Camacho, Cleber P. [UNIFESP]
Dias da Silva, Magnus R. [UNIFESP]
Maciel, Rui M. B. [UNIFESP]
Vieira, Jose Gilberto H. [UNIFESP]
Martins, Joao Roberto M. [UNIFESP]
author2_role author
author
author
author
author
author
author
author
author
author
author
dc.contributor.author.fl_str_mv Alves, Thalita G. [UNIFESP]
Kasamatsu, Teresa S. [UNIFESP]
Yang, Ji H. [UNIFESP]
Meneghetti, Maria Cecilia Z. [UNIFESP]
Mendes, Aline [UNIFESP]
Kunii, Ilda S. [UNIFESP]
Lindsey, Susan C. [UNIFESP]
Camacho, Cleber P. [UNIFESP]
Dias da Silva, Magnus R. [UNIFESP]
Maciel, Rui M. B. [UNIFESP]
Vieira, Jose Gilberto H. [UNIFESP]
Martins, Joao Roberto M. [UNIFESP]
description Context: Calcitonin (CT) is a sensitive marker of medullary thyroid carcinoma (MTC) and is used for primary diagnosis and follow-up after thyroidectomy. However, persistently elevated CT is observed even after complete surgical removal without evidence of a recurrent or persistent tumor. Objective: To investigate the presence of assay interference in the serum CT of MTC patients who are apparently without a structural disease. Patients and Methods: We studied three index MTC cases for CT assay interference and 14 patients with metastatic MTC. The CT level was measured using an immunofluorometric assay. Screening for assay interference was performed by determination of CT levels before and after serum treatment with polyethylene glycol. Additionally, samples were analyzed by chromatography on ultra-performance liquid chromatography and protein A-Sepharose. Results: Patients with biochemical and structural disease showed CT mean recovery of 84.1% after polyethylene glycol treatment, whereas patients suspected of interference showed recovery from 2-7%. The elution profile on UPLC showed that the immunometric CT from these three patients behaved like a high molecular mass aggregate (>300 kDa). Additionally, when these samples were applied to the protein A-Sepharose, CT immunoreactivity was retained on the column and was only released after lowering the pH. Conclusions: For the first time, our results show the presence of a novel pitfall in the CT immunoassay: "macrocalcitonin." Its etiology, frequency, and meaning remain to be defined, but its recognition is of interest and can help clinicians avoid unnecessary diagnostic investigations and treatment during the follow-up of MTC.
publishDate 2016
dc.date.none.fl_str_mv 2016
2020-08-21T17:00:26Z
2020-08-21T17:00:26Z
dc.type.driver.fl_str_mv info:eu-repo/semantics/article
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
format article
status_str publishedVersion
dc.identifier.uri.fl_str_mv http://dx.doi.org/10.1210/jc.2015-3137
Journal Of Clinical Endocrinology & Metabolism. Washington, v. 101, n. 2, p. 653-658, 2016.
10.1210/jc.2015-3137
WOS000378642700035.pdf
0021-972X
https://repositorio.unifesp.br/handle/11600/57993
WOS:000378642700035
url http://dx.doi.org/10.1210/jc.2015-3137
https://repositorio.unifesp.br/handle/11600/57993
identifier_str_mv Journal Of Clinical Endocrinology & Metabolism. Washington, v. 101, n. 2, p. 653-658, 2016.
10.1210/jc.2015-3137
WOS000378642700035.pdf
0021-972X
WOS:000378642700035
dc.language.iso.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv Journal Of Clinical Endocrinology & Metabolism
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv 653-658
application/pdf
dc.coverage.none.fl_str_mv Washington
dc.publisher.none.fl_str_mv Endocrine Soc
publisher.none.fl_str_mv Endocrine Soc
dc.source.none.fl_str_mv reponame:Repositório Institucional da UNIFESP
instname:Universidade Federal de São Paulo (UNIFESP)
instacron:UNIFESP
instname_str Universidade Federal de São Paulo (UNIFESP)
instacron_str UNIFESP
institution UNIFESP
reponame_str Repositório Institucional da UNIFESP
collection Repositório Institucional da UNIFESP
repository.name.fl_str_mv Repositório Institucional da UNIFESP - Universidade Federal de São Paulo (UNIFESP)
repository.mail.fl_str_mv biblioteca.csp@unifesp.br
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