I have a mesentery neoplasm that is most likely sclerosing mesenteritis, but it has not been definitely diagnosed, because surgeons have not been able biopsy it due to its location at the root of the mesentery among major arteries and loops of small intestine. It was first discovered 11/10/22 when I went to the ER with a partial small bowel obstruction. I had CT scan of abdomen and chest and MRI of abdomen, which revealed a heavily calcified mass 4.6 cm x 4.2 cm x 3.6 cm. Lab tests (Cromogranin A and 5-HIAA) were done to rule out carcinoid. Ga-68 Dotatate PET scan was done and was negative (no radiotracer uptake of the mass or adjacent lymph nodes). I am scheduled to have a repeat PET scan in March to see if the mass has changed in size. While in the hospital I had a diagnostic laparoscopy. The female surgeon was able to insert her small hand in my abdomen and palpate the mass, but even with that there was no safe place to obtain a core biopsy. The surgeon stated that if the mass grows in size and leads to a complete bowel obstruction, "a small bowel bypass would be difficult and would likely result in short gut syndrome with <60-70 cm of currently uninvolved small bowel." So at the moment I am in a watch and wait status with no medications given and instructions to eat small portions frequently throughout the day. No symptoms of SBO lately. I am not in a lot of pain, just dealing with a constant sense of fullness/bloating and a noticeable distension of my abdomen. The mass seems to be interfering with nutrient assimilation. Serum calcium, albumin, and vitamin levels have been below normal so I am trying to compensate by eating lots of protein and taking supplements. The oncology doctor that I saw on January 5th ordered a serum serotonin level, thinking it might indicate a certain type of tumor if the level was high. However, it was low instead (17 ng/mL) where the standard range is 50-220 mg/mL I am wondering if this low level of serotonin could be interfering with my sleep and causing depression. Has anyone in this group had their serotonin level tested? (Serotonin is produced in the brain and the small intestine).