The researchers found cancer cells in some of this tissue, and suggested that the fluid-filled spaces within the interstitium might be one of the ways cancer cells can spread, and may be how cancer ends up in the lymph nodes.
Neil Theise, a professor at the School of Medicine of the University of NY and the new study's author, explained that this new organ, the Interstitium, has not been discovered before due to the fact that scientists tend to examine fixed tissue.
Humans have been studying the anatomy of our own bodies for thousands of years - but, to this day, scientists are still uncovering new secrets. In addition, the fluid-filled compartments that make up the interstitium take on the role of protecting tissues during daily functions, by operating as shock absorbers, Dr. Theise revealed.
"Our findings necessitate reconsideration of numerous normal functional activities of different organs and of disordered fluid dynamics in the setting of disease, including fibrosis and metastasis", the researchers write in a published paper in Scientific Reports ("Structure and Distribution of an Unrecognized Interstitium in Human Tissues").
"What we saw in this layer of the bile duct is this open fluid filled space supported by this collagen bundle latticework", Theise, who now works at New York University School of Medicine told Reuters on Tuesday.
The interstitial space is the major fluid compartment in the body and the primary source of lymph, the authors note. This process drains the fluid in the tissue, hence, interstitium, being fluid, has never been observed until the researchers used the confocal laser. The doctors collaborated with New York University pathologist Dr. Neil Theise to further explore the structure and function of the newly identified organ. While two-thirds of that liquid remains inside cells, the remaining water called interstitial fluid is free to move throughout cavities inside the body.
Nevertheless, Dr. Nathanson is not convinced the interstitium is actually an organ, but rather "a new component that is common among a variety of organs", he told CNN.
The findings have been met with applause throughout the medical community, with anticipation the deciphering the tissues complexities will become a leading field of research in the fight against cancer.
With the pCLE, the researchers noticed an odd "reticular pattern" in the tissue around the bile duct they were examining.
This organ is believed to be the reason for the spread of cancer and that is why the researchers think that interstitium can help develop new tests for cancer.
Researchers collected tissues samples of bile ducts from 12 cancer patients during surgery. The discovery of the instrument was done with the help of a confocal laser intrasung microscope, which "sees" the living tissues.
It was also known that cells immediately around tumours can be incredibly important in supporting and fostering the growth and spread of tumour cells in the body, Dr O'Connor said. However, pCLE enabled the scientists to examine living tissue, allowing the structure of the interstitium to remain visible. The patterned tissue had dark, branching bands surrounding large, dye-filled polygonal spaces.