For cancers, such as mesothelioma, that spread to the lining of the stomach, detecting the cancer is very difficult with CT or MRI scans. Researchers at the University of Chicago want to find out if the new experimental MRI and ultrasound imaging techniques do a better job of detecting these cancers. Researchers will use new MRI and ultrasound techniques to see if it can find evidence of cancer that has spread to the lining of the abdomen, and right now these new techniques are only used for research.

Inclusion Criteria:

1. 18 years old or older
2. Biopsy-proven MPM
3. Surgery for PM planned at UCM within 60 days
4. Able to tolerate CT, MRI, US scans, and surgery
5. Able to provide written informed consent
6. For women of child bearing age, ability and willingness to use appropriate contraceptive methods before imaging and for a period of 365 days thereafter.

Exclusion Criteria:

1. Pregnancy / Breastfeeding
2. Allergy or intolerance to iodinated or gadolinum contrast dyes
3. Contraindications to CT or MRI imaging including chronic kidney disease with GFR <60mL/min/1.73m2
4. Bioimplants unsuitable for MRI imaging (activated by mechanical, electronic, radiofrequency, or magnetic means), such as cochlear implants, pacemakers, neurostimulators, biostimulators, electronic infusion pumps
5. Permanent tattoos or eyeliner with magnetic dyes
6. Subjects with shrapnel or metal fragments lodged in the body
7. Anxiety, claustrophobia, or any medical condition that would preclude lying still in an MRI scanner for 1-1.5 hours
8. Cardiac, circulatory, or perspiration problems leading to impaired thermoregulation
9. Respiratory or cardiac impairment limiting the ability to lie flat
10. Inability to breath-hold for MRI acquisition
11. Vascular or aneurysm clips or any other surgical implant that is not MRI-compatible
12. Any other ferromagnetic bioimplant that would be damaged by MRI
13. Mental, cognitive, or mental health impairments that preclude the subject from providing informed consent or adhering to the treatment protocol
14. Subjects unable to adhere to the protocol or communicate effectively with researchers
15. Imprisoned subjects
16. Subjects with history of prior CRS/HIPEC or other peritonectomy surgery that might alter characteristics of the peritoneum