Isolated splenic metastasis from lung cancer: ringleader of continuous fever

The spleen is an infrequent metastatic organ of solid tumours, the prevalence of which ranges between 2.3% and 7.1% in populations with cancer as determined through autopsy. The most common sources of metastasis are breast, lung, colorectal and ovarian carcinoma and melanoma. Isolated metastasis of the spleen is rarely reported with only 93 cases from all sources having been reported up to 2007. Therefore, isolated splenic metastasis from primary lung cancer is exceedingly rare with only 11 cases reported to date. Herein, we report a rare case of isolated splenic metastasis in a 49-yr-old female 3 months after lobectomy for an undifferentiated large cell carcinoma in the right lung (pT(2a)N₀M₀). The only symptom the patient presented with was continuous high fever, which had never been previously reported. This patient presented diagnostic challenges due to the presentation of high fever, leukoapenia after chemotherapy and the cystic splenic mass, all of which led to the initial consideration of splenic abscess. The patient's high fever resolved rapidly after splenectomy and splenic metastasis was confirmed by pathological findings. We also reviewed all 11 reported previously cases and summarised the characteristics and appropriate management of isolated splenic metastasis from lung cancer.