Differential Diagnosis for Elevated CEA and CA 125 in Peritoneal Carcinomatosis
Single Most Likely Diagnosis
- Ovarian Cancer: The combination of peritoneal carcinomatosis, liver lesions, and significantly elevated CA 125 levels is highly suggestive of ovarian cancer, especially given that CA 125 is a tumor marker commonly associated with this malignancy. Elevated CEA can also be seen in ovarian cancer, particularly in more advanced stages.
Other Likely Diagnoses
- Gastrointestinal Cancer (e.g., Colon, Stomach): Elevated CEA levels are commonly associated with gastrointestinal cancers, and peritoneal carcinomatosis can occur in these malignancies. While CA 125 can be elevated in various conditions, its significant elevation alongside CEA and the presence of peritoneal carcinomatosis could suggest a gastrointestinal primary with metastasis to the peritoneum and liver.
- Peritoneal Mesothelioma: Although less common, peritoneal mesothelioma can present with peritoneal carcinomatosis and elevated tumor markers, including CA 125. However, the significant elevation of both CEA and CA 125 might be less typical for mesothelioma compared to epithelial ovarian cancer.
Do Not Miss Diagnoses
- Pseudomyxoma Peritonei: A rare condition characterized by recurrent mucinous ascites causing abdominal distension, often associated with a primary mucinous tumor of the appendix. It's crucial not to miss this diagnosis due to its unique management and relatively better prognosis compared to other malignancies causing peritoneal carcinomatosis.
- Intra-abdominal Desmoplastic Small Round Cell Tumor: A rare and aggressive tumor that can present with peritoneal carcinomatosis and may have elevated tumor markers. Early diagnosis is critical due to its poor prognosis and the need for aggressive treatment.
Rare Diagnoses
- Primary Peritoneal Cancer: A rare malignancy that arises from the peritoneum and can mimic ovarian cancer in presentation, including elevated CA 125 levels. It is considered in the differential diagnosis of peritoneal carcinomatosis with unknown primary.
- Serous Surface Papillary Carcinoma of the Peritoneum: Another rare tumor that can present similarly to ovarian cancer, with peritoneal carcinomatosis and elevated CA 125. Its distinction from ovarian cancer is important for treatment planning and prognosis.