Pitfalls in oncology: a unique case of thoracic splenosis mimicking malignancy in a patient with resected breast cancer

Abstract

Thoracic splenosis (TS) is a condition of autotransplantation of splenic tissue into the pleural cavity after thoraco-abdominal trauma, with diaphragmatic and spleen injury. It is usually asymptomatic and discovered as an incidental finding at imaging performed for other reasons. Its differential diagnosis regards different benign and malignant conditions and should be discerned avoiding invasive procedures. We report a case of thoracic mass associated with pleural nodules mimicking malignancy in a patient with resected breast cancer for whom a diagnosis of TS was made early by using non-invasive methods. Briefly, we review the literature data on TS, comment concisely the possible implications of using invasive procedures and describe the current non-invasive techniques available. Furthermore, we highlight the importance of an accurate medical history collection, the role of the multidisciplinary board and their impact on treatment decision making. Finally, we conclude that clinical information and imaging would be the discriminating factors to avoid unnecessary invasive procedures.

Keywords: Thoracic splenosis (TS); breast cancer; pleural nodules; radionuclide scan; thoracic mass.

Figure 1

Chest X-ray shows 4-cm retrocardiac round opacity (red arrows), suspicious for malignancy.

Figure 2

Computed tomography (CT) scan shows the presence of a 4.5-cm paracardiac solid mass (A,B), associated with some left-sided pleural nodules of 2 cm in maximum diameter (C), and a solid mass in spleen bed (D).

Figure 3

Fused SPECT-CT imaging. (A) 99mTc-nanocolloid scan shows uptake in paracardiac solid mass, confirming the diagnosis of thoracic splenosis (TS) (left panel CT scan, right panel fused images); (B) 99mTc-nanocolloid scintigraphy (left panel CT scan, right panel fused images) reveals radiotracers uptake in the pleural nodule of the left hemithorax; (C) the solid mass in the splenic space shows radiotracer uptake at 99mTc-nanocolloid scintigraphy (left panel CT scan, right panel fused images). SPECT, single photon emission computed tomography; CT, computed tomography.