Choriocarcinoma Masquerading as Lung Abscess or Lung Cancer: A Case with Atypical Imaging Findings

Background Choriocarcinoma is a highly malignant trophoblastic tumor. However, the awareness surrounding its atypical clinical presentation is insufficient. The presence of a solitary lung lesion without uterine lesions often leads to misdiagnosis or missed diagnosis, which in turn causes delayed treatment or even multiple metastases throughout the body. Case presentation We present the case of a 36-year-old female patient who was misdiagnosed with a lung abscess and received suboptimal anti-infective treatment. She then underwent left upper lobectomy and was misdiagnosed with lung cancer by abscess incision and drainage in thoracic surgery, however, the results after pleural effusion removal were suboptimal. During this time a breast nodule was found, and a large segment of the right breast was excised and misdiagnosed as breast cancer but was finally diagnosed as choriocarcinoma with multiple metastases of lung and breast. Multiple metastases were also detected in the head, liver, kidney, and bones. The patient underwent multiple adjuvant chemotherapies. The blood β-hCG level gradually declined to normal. When we reported this case, that is, seven months after the diagnosis, the patient was still alive, and the disease was stable without progress. Conclusion Choriocarcinoma with a solitary lung lesion as the first presentation and no lesions in the uterus is clinically rare. This may lead to a delay in diagnosis due to poor awareness of the disease and the appearance of multiple metastases throughout the body. Clinicians should be more aware of choriocarcinoma with an atypical presentation to reduce misdiagnosis and missed diagnosis.