In Traditional Chinese Medicine, the Spleen-Pancreas system (also commonly just referred to as the Spleen) encompasses all the other organs of digestion, including the stomach and small & large intestine.
Traditional Oriental Medicine always views the physical organs, along with their corresponding energy meridian pathways, as an integrated whole. Because of this, when Eastern medicine talks about an organ, it is referring to the entire system which often includes other associated parts of the body, not just the local area of the physical organ.
In Traditional Oriental Medicine, the understanding of the organs is different than that of Western medicine. The physical organs, along with their corresponding energetic meridian pathways are never regarded as independent systems but instead, are always viewed in relation to the rest of the body.