Fig 2. An illustration of the IMC multi-feature observations from a single subject.

In the IMC data of a single subject, we focus first on the Cytokeratin marker, which is used as an indicator of tumor cells. We select N ROIs located at the highest Cytokeratin expression levels. These ROIs are patches of size b × b μm², where here b set to 35. We assume that these ROIs have intrinsic hidden states represented by x_i. The expression of all 29 markers at these ROIs are viewed as the multi-feature observations ${\left\{f_j\left(x_i\right)\right\}}_{j=1}^{29}$ for i = 1, …, N.