(90 days)
The CellSearch™ Circulating Tumor Cell Kit is intended for the enumeration of circulating tumor cells (CTC) of epithelial origin (CD45-, EpCAM+, and cytokeratins 8, 18+, and/or 19+) in whole blood.
The presence of CTC in the peripheral blood, as detected by the CellSearch™ Circulating Tumor Cell Kit, is associated with decreased progression free survival and decreased overall survival in patients treated for metastatic breast, colorectal or prostate* cancer. The test is to be used as an aid in the monitoring of patients with metastatic breast, colorectal or prostate cancer. Serial testing for CTC should be used in conjunction with other clinical methods for monitoring metastatic breast, colorectal and prostate cancer. Evaluation of CTC at any time during the course of disease allows assessment of patient prognosis and is predictive of progression free survival and overall survival.
*Metastatic prostate cancer patients in this study were defined as having two consecutive increases in the serum marker PSA above a reference level, despite standard hormonal management. These patients are commonly described as having androgen-independent, hormone-resistant, or castration-resistant prostate cancer.
The CellSearch" Circulating Tumor Cell Kit contains a ferrofluid-based capture reagent and immunofluorescent reagents. The ferrofluid reagent consists of nanoparticles with a magnetic core surrounded by a polymeric layer coated with antibodies targeting the EpCAM antigen for capturing CTC. After immunomagnetic capture and enrichment, fluorescent reagents are added for identification and enumeration of CTC. The fluorescent reagents include the following: anti-CK-Phycoerythrin (PE) specific for the intracellular protein cytokeratin (characteristic of epithelial cells), DAPI which stains the cell nucleus, and anti-CD45-Allophycocyanin (APC) specific for leukocytes.
The reagent/sample mixture is dispensed by the CellTracks® AutoPrep® System into a cartridge that is inserted into a MagNest® cell presentation device. The strong magnetic field of the MagNest® device attracts the magnetically labeled epithelial cells to the surface of the cartridge. The CellTracks Analyzer II or CellSpotter® Analyzer automatically scans the entire surface of the cartridge, acquires images and displays any event to the user where CK-PE and DAPI fluorescence are co-located. Images are presented to the user in a gallery format for final classification. An event is classified as a tumor cell when its morphological features are consistent with that of a tumor cell and it exhibits the phenotype EpCAM+, CK+, DAPI+ and CD45 -.
Here's an analysis of the acceptance criteria and the study that proves the device meets them, based on the provided text:
Device: CellSearch™ Circulating Tumor Cell Kit (expanded indications for use in Metastatic Prostate Cancer)
1. Table of Acceptance Criteria and Reported Device Performance:
| Acceptance Criteria Category | Specific Metric (as applicable) | Predetermined Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|---|---|
| Recovery | Regression analysis (slope, R-squared) | Slope = 1.0 (ideal) | Y = 0.93x + 3.87, R=0.999 (0.999) |
| Average recovery: 93% | |||
| Linearity / Reportable Range | Regression analysis (slope, R-squared) | Slope ≈ 1.0 (after factoring out recovery loss) | Slope = 1.007, Intercept = 3.0, R² = 0.990 (R = 0.995) |
| Range: 0 to 1238 tumor cells | |||
| Limits of Detection | Minimum detectable CTC count | 1 CTC per 7.5 mL | 1 CTC per 7.5 mL |
| System Reproducibility (Control) | % CV (low control) | Not explicitly stated, but generally 1 and p 1 and p 1 and p 1 and p |
§ 866.6020 Immunomagnetic circulating cancer cell selection and enumeration system.
(a)
Identification. An immunomagnetic circulating cancer cell selection and enumeration system is a device that consists of biological probes, fluorochromes, and other reagents; preservation and preparation devices; and a semiautomated analytical instrument to select and count circulating cancer cells in a prepared sample of whole blood. This device is intended for adjunctive use in monitoring or predicting cancer disease progression, response to therapy, and for the detection of recurrent disease.(b)
Classification. Class II (special controls). The special control for this device is FDA's guidance document entitled “Class II Special Controls Guidance Document: Immunomagnetic Circulating Cancer Cell Selection and Enumeration System.” See § 866.1(e) for availability of this guidance document.