Liver metastasis from retroperitoneal leiomyosarcoma 18 years after primary tumour resection: report of a case

Leiomyosarcoma is a histological subtype of soft tissue sarcoma that arises from smooth muscle cells and account for up to 15% of all soft tissue carcinomas that form involuntary muscles, commonly found in the retroperitoneum, uterus, stomach, small intestine and vascular tissue.  Surgery with a wide margin of complete excision is the most effective treatment. Liver and lungs are the most common sites of metastasis in leiomyosarcoma and it generally occurs within the first 3 years. Liver metastasis are usually observed in the recurrence of visceral and retroperitoneal sarcomas. We report a case of 70-year-old female patient with liver metastasis, detected 18 years after resection of a primary retroperitoneal leiomyosarcoma on the right side. Abdominal CT scan showed sharply contoured, hypodense structure 7.3 x 5.3 cm. Further MRI examination revealed suspicious for malignant lesion. US guided CORE biopsy was performed after detecting suspicious liver lesion. Pathohistological and immunohistochemistry examination of biopsy material showed high-grade (Grade 2) leiomyosarcoma liver metastasis. According to oncologic council surgical liver metastasis resection was recommended. The surgical indication was single liver metastases, without evidence of extrahepatic disease. Conventional right side hemi hepatectomy using OLYMPUS ultrasonic surgery system SonoSurg was performed. Size of metastatic lesion 88x55x70 mm. Negative resection margins were obtained. Lesion consists of spindle cells with cigar-shaped nuclei, expressive cell polymorphism, areas of necrosis and abundant mitoses ≥10 per 10 high-power fields. Positive for smooth muscle marker actin and negative for CD117, DOG-1 and S100, Ki-67 index 10% by immunohistochemistry. Further follow-up by medical oncologist. Early diagnosis and surgical removal of the tumor is the only potentially curative option for liver metastasis of leiomyosarcoma. To the best of our knowledge, this case have had the longest disease-free interval before metastasis to the liver.