A valid and specific blood draw that could help diagnose, determine the presence of a response to therapy, and be used as follow-up (instead of scans!) would be sooooooooooo awesome!!!! Now there's this:
Melanoma antigens are biomarkers for ipilimumab response. Arenberger, Fialova, Gkalpakiotis, et al. J Eur Acad Dermatol Venereol. 2016 Aug 24.
Patients (n=62) with metastatic melanoma in unresectable stage III or metastatic stage IV treated with ipilimumab were recruited prospectively. The values of 4 melanoma markers on circulating cells Melan-A, gp100, MAGE-3 and MIA prior to the treatment and within the therapy were compared to the data collected at baseline - after the melanoma surgery.
The immunotherapy pretreatment marker level was found to be prognostic of overall survival, lower levels were linked to longer survival time. Moreover, longitudinal follow-up of melanoma markers in patients treated with ipilimumab correlates with therapy response. A decline of marker levels by greater than 30% at week 6 (in 83% of the responding subjects) to week 9 (in all responders) of ipilimumab administration was associated with response to therapy. Elevation of the tumor markers during the treatment precedes clinical progression and gives an early warning of treatment failure.
Melanoma circulating cells hold potential as predictive and pharmacodynamic biomarker of immunotherapy.