Left upper quadrant mass

The most frequent left upper quadrant mass is an enlarged spleen. Splenomegaly occurs in a wide variety of disease states:

• Infectious diseases such as tuberculosis, malaria, infectious mononucleosis, and subacute bacterial endocarditis are often accompanied by an enlarged spleen. (The spleen is occasionally the site of an abscess, particularly with subacute bacterial endocarditis or any other bacteraemic state.)
• Myeloproliferative disorders such as myelofibrosis may be characterized by splenomegaly.
• Splenomegaly occurs when the veins draining the spleen are obstructed, as in portal hypertension or splenic vein thrombosis. Both pancreatic cancer and pancreatitis can cause splenic vein thrombosis.
• Metastases may occur in the spleen; however, the spleen is not often the site of neoplastic involvement.
• Lymphoma and leukaemia may involve the spleen directly or cause splenomegaly as a secondary phenomenon because blood production is disorganized.
• Storage disorders such as Gaucher’s disease may cause splenomegaly.

Fluid-filled masses.

A left upper quadrant fluid-filled mass is quite common and may be a renal mass such as hydronephrosis or a large renal cyst, a splenic cyst, an adrenal cyst, or a pancreatic pseudocyst.

Neoplasms.

Neoplastic masses in the left upper quadrant include retroperitoneal sarcomas, adrenal tumours, which are usually small (e.g., metastases, pheochromocytoma) but occasionally become large, and pancreas and kidney cancers, which can spread into the left upper quadrant and cause a palpable abdominal mass.

Reference

1. Ball JW et al. Abdomen. In: Seidel's Guide to Physical Examination. 10th ed. St Louis, MO: Elsevier; 2023:chap 18.