Differential Diagnosis for a Pelvic Mass with Mildly Elevated CEA
Single most likely diagnosis
- Colorectal cancer: A mildly elevated CEA (Carcinoembryonic antigen) level, combined with a pelvic mass, suggests colorectal cancer as the most likely diagnosis. CEA is a tumor marker often associated with colorectal cancer, and a pelvic mass could represent a primary tumor or metastasis.
Other Likely diagnoses
- Ovarian cancer: While CEA is not as specific for ovarian cancer as it is for colorectal cancer, ovarian tumors can sometimes cause an elevation in CEA levels. A pelvic mass in a female patient could very well be an ovarian tumor.
- Uterine cancer: Similar to ovarian cancer, uterine cancers (such as endometrial cancer) might present with a pelvic mass and could potentially cause a mild elevation in CEA, although this is less common.
- Other gastrointestinal cancers: Although less likely than colorectal cancer, other gastrointestinal cancers (like gastric or pancreatic cancer) could potentially present with a pelvic mass and elevated CEA, especially if there is metastasis to the pelvis.
Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Metastatic disease from other primary sites: It's crucial not to miss the possibility of metastasis from other primary cancer sites (e.g., breast, lung) to the pelvis, which could also present with a mass and potentially elevate CEA levels, depending on the primary tumor's characteristics.
- Lymphoma: Although lymphoma might not typically cause a significant elevation in CEA, it can present with a pelvic mass and is a critical diagnosis not to miss due to its potential for aggressive behavior and the need for prompt treatment.
Rare diagnoses
- Neuroendocrine tumors: These can occasionally present with a pelvic mass and might cause an elevation in CEA, especially if they are of gastrointestinal origin.
- Sarcomas: Rarely, soft tissue sarcomas or other sarcomas within the pelvis could present as a mass and potentially have an elevated CEA, although this is uncommon.
- Benign conditions with elevated CEA: Certain benign conditions, such as diverticulitis or inflammatory bowel disease, can also cause mild elevations in CEA, though they would be less likely to present with a significant pelvic mass.