We present a clinical case of step-by-step treatment of a patient with a tumor of the left lung upper lobe and a pronounced aortic valvular disease. The combination of concurrent pathologies always requires a thorough selection of the treatment approach. The risks of simultaneous surgical interventions are associated with high intraoperative and early postoperative complications. The selected approach of the stepwise treatment of aortic valve replacement followed by stereotactic hypofractionated radiation therapy has demonstrated the outcomes comparable to those of radical surgery. The compensation of hemodynamic parameters and a full local response during 18-month follow-up has confirmed the appropriateness of a patient-specific complex treatment approach, with a high quality of life maintained.