Metachronous Squamous Cell Carcinomas of the Uterine Cervix and Lung: True Metachrony or Metastasis.

Human papillomaviruses (HPV) are a big group of infection agents with oncogenic potential, especially regarding squamous epithelium. Some high-risk variants are key in the development of squamous cell carcinomas (SCC) across multiple systems, the most affected of which is the female reproductive system, but also parts of the gastrointestinal tract, head, and neck SCC, and cutaneous and pulmonary (bronchogenic) SCCs. In cases where a patient develops two SCCs in different systems, often the main question is whether these tumors are synchronous, metachronous, or if one of the tumors is a metastasis from the other, with HPV testing and stereotype identification often being of aid in differentiating between these. Herein, we report the case of a female patient in her 50s, initially diagnosed with SCC of the uterine cervix. The patient remained stable for three calendar years after completing preoperative radiotherapy, surgical resection, and postoperative chemo-radiotherapy. At that point, she developed respiratory symptoms, and radiography suggested a pulmonary malignancy. After undergoing surgical resection of the pulmonary lesion, histological specimens were initially interpreted to be a metachronous pulmonary SCC. Immunohistochemical testing proved that both the cervical and pulmonary lesions were HPV-associated, with further testing proving that both lesions were associated with high-risk HPV (genotype 16). Based on the clinical history and aggregated data, the pulmonary lesion was interpreted as a metastatic and not a metachronous one, and the patient is currently undergoing treatment for metastatic disease.