Undifferentiated Pleomorphic Sarcoma: The importance of considering the Oncogenic and Immune-suppressant Role of the Human T-Cell Lymphotropic Virus Type 1 (HTLV-1). A Case Report

LUPPO SERGIO; BERINI C; CÁNEPA C; SANTINI ARAUJO E; BIGLIONE M

Frontiers in oncology

Editorial Manager

Año: 2017

2234-943X

Introduction: The sarcomas are soft tissue malignant tumors accounting for the 0.7 % of malignant tumors in general with a rate of 3 by 100 000. The Undifferentiated Pleomorphic Sarcoma (UPS) is a high grade tumor included in the group of soft tissue tumors. The UPS with giant cells is very unusual especially in young adults before age 40. Human T-Cell Lymphotropic Virus type-1 (HTLV-1) is a human retrovirus classified as group 1 human carcinogens by The International Agency for Research on Cancer (IARC), that causes an aggressive malignancy known as adult T-cell lymphoma/leukemia (ATLL) and a progressive chronic inflammatory neurological disease named HTLV-1 associated myelopathy/ tropical spastic paraparesis (HAM/TSP). Case report: We describe a case of an UPS in a woman who developed a HAM/TSP 3 years before. In 2013 the patient started with neurological symptoms: weakness in the legs and bladder dysfunction. One year later, developed mild paraparesis in both extremities and detection of anti-HTLV-1 antibodies in plasma and LCR confirmed a HAM/TSP. In November 2015 a benign ganglion cyst was firstly suspected without intervention and by March 2016 a sarcoma was confirmed. Three weeks after surgical resection the tumor aroused in deep tissue and behaved aggressively, implicating a curative wide excision to the fibula, joint reconstruction and soft tissue graft. Histopathology exam confirmed an UPS with giant cells. Concluding remarks: Reaching an accurate and timely diagnosis of UPS can be challenging due to difficulty in diagnosis/classification and delayed consultation. However the unapparent subclinical immunodeficiency state due to HTLV-1 infection deserves to be considered the possibility of developing any type of cancer. Moreover, considering the high grade of UPS and the progressive invalidating myelopathy caused by HTLV-1 treatment should be carefully evaluated to positively impact on the patient´s life expectancy.HTLV-I Tax carries out essential functions in order to override cell cycle checkpoints and deregulate cellular division. In addition, Tax expression is associated with increased DNA damage and genome instability. Since Tax can inhibit multiple DNA repairpathways and stimulate unfaithful DNA repair or bypass checkpoints, these processes allow accumulation of genetic mutations in the host genome. Given this, a "Random Mutagenesis" transformation model seems more suitable to characterize the oncogenic activities of HTLV-I.