论文信息 - Validation of Neurokinin A Assays in the United States and Europe

Validation of Neurokinin A Assays in the United States and Europe

Objectives: International cooperative group trials require specific, sensitive biomarker assays that are validated between continents. Neurokinin A (NKA) has been shown to be a powerful independent predictor of a poor prognosis in well-differentiated midgut neuroendocrine tumors. We hypothesized that NKA concentrations of clinical specimens evaluated in NKA assays in the United States and the United Kingdom would be equivalent, even though assay techniques were significantly different. Methods: Frozen clinical specimen aliquots were shipped from the United States to the United Kingdom (n = 67), and from United Kingdom to the United States (n = 50). In addition, spiked plasma standards and medium-spiked standards were exchanged. Samples from the United States were directly assayed in a radioimmunoassay, whereas the UK specimens were extracted, and the reconstituted specimens assayed in the radioimmunoassay. Neurokinin A values from the 2 studies were analyzed by regression analysis. Results: The NKA values from the US and UK laboratories were essentially identical (United States to United Kingdom, r2 = 0.88, P < 0.0001; and United Kingdom to United States, r2 = 0.96, P < 0.0001). Conclusions: Validation of biomarker assays across continents will ensure that laboratory observations made by researchers are equivalent and that prediction of clinical outcomes based on these assays is also reliable.

[1] G. Mamikunian,et al. Development of a Highly Sensitive and Specific Carboxy-Terminal Human Pancreastatin Assay to Monitor Neuroendocrine Tumor Behavior , 2010, Pancreas.

[2] A. Vinik,et al. Biochemical Testing for Neuroendocrine Tumors , 2009, Pancreas.

[3] J. Ardill. Circulating markers for endocrine tumours of the gastroenteropancreatic tract , 2008, Annals of clinical biochemistry.

[4] C. Patterson,et al. A rapid rise in circulating pancreastatin in response to somatostatin analogue therapy is associated with poor survival in patients with neuroendocrine tumours , 2008, Annals of clinical biochemistry.

[5] M. Stridsberg,et al. Tachykinins in endocrine tumors and the carcinoid syndrome. , 2008, European journal of endocrinology.

[6] G. Mamikunian,et al. Validation of Serum Versus Plasma Measurements of Chromogranin A Levels in Patients With Carcinoid Tumors: Lack of Correlation Between Absolute Chromogranin A Levels and Symptom Frequency , 2006, Pancreas.

[7] C. Patterson,et al. Circulating markers of prognosis and response to treatment in patients with midgut carcinoid tumours , 2006, Gut.

[8] J. Ardill,et al. The importance of the measurement of circulating markers in patients with neuroendocrine tumours of the pancreas and gut. , 2003, Endocrine-related cancer.