Timoma, un tumor maligno poco frecuente con resolución quirúrgica mediante videotoracoscopia. Reporte de un caso

BACKGROUND: Thymomas are rare epithelial tumors which originate from the thymic gland, with an incidence of 0.13 cases per 100 000 inhabitants in one year, more commonly seen between 40 and 60 years of age. These tumors do not present specific clinical signs and 30% to 60% of the patientsare asymptomatic; in most cases, the tumors are found incidentally by CT-scans. The primary treatment involves surgery. There are few reports in Ecuador, thus it is important to publish this clinical case for the knowledge of the medical community. CASE REPORT: 62-year-old male patient, with a history of osteoarthritis and smoking. He came with a four-month history of chest pain, productive cough that progressed later to haemoptysis and significant unquantified weight loss. The chest CT scan reported a mass located in the right anterior and middle mediastinum, causing mass effect on the heart and great vessels; also, there were small pretracheal mediastinal adenopathies. EVOLUTION: After the diagnosis of a mediastinal mass, highly suggestive of a tumor dependent on the thymus, we decided surgical approach by video-assisted thoracoscopy. Incomplete R1 resection (focally in contact with the resection limit) was achieved, with a positive biopsy for thymoma, type AB (WHO classification), stage IIB (modified Masaoka classification). Adjuvant radiotherapy was administered, presenting complete remission of the disease, with no recurrence during 2-year follow up. CONCLUSION:Thymomas are rare malignant tumors; its first-line treatment involves radical surgery in Masaoka stages I, II and III. Video-assisted thoracoscopy thymectomy is a less invasive procedure and reduces complications, improving postoperative life quality; however, the possible need to add adjuvant radiotherapy in cases of incomplete resection with this technique should be taken into consideration.