Effect of bacterium in the malignant wounds of soft tissue sarcoma

Malignant wounds (MWs) are rare skin lesions, which accompany ulceration, necrosis and infection caused by infiltration or damage by malignant tumor. The present study aimed to investigate the bacterial etiology implicated in MW in soft tissue sarcoma (STS), and the effectiveness of culture-guided perioperative antibacterial administration. A retrospective evaluation was conducted on medical records of patients who presented with MW between 2006 and 2020. A total of seven patients were included in the present study, in whom all tumors were relatively large (>5 cm) and high-grade. Subsequently, five patients underwent limb-sparing surgery, and three patients had distant metastases with a 5-year overall survival of 71%. Preoperative microbiological sampling from the wound identified 11 different bacterial strains in five patients. The infections were polymicrobial with an average of 2.6 strains isolated per patient (1 aerobic, 1.6 anaerobic bacteria). They were predominantly methicillin-sensitive Staphylococcus aureus. Patients with MWs from STS reported symptoms, including bleeding (71%), exudation (71%) and malodorous wound (43%) at the initial presentation; these completely resolved after surgery. All but one patient reported pain at the MW site with an average numeric rating scale of 4.4 at presentation that decreased to 1.4 (P=0.14) and 0.6 (P=0.04) one and two weeks after surgery, respectively. The patients had elevated C-reactive protein (71%), anemia (57%), low albumin (86%) and renal/liver dysfunction (14–29%). One patient was diagnosed with sepsis. Surgical resection afforded symptomatic relief and resolution of abnormal laboratory values. Although selected antibiotics were administered in four patients based on the preoperative antibiotic sensitivity test, surgical site infection (SSI) occurred in three patients. Therefore, the effectiveness of the selected antibiotics based on the results of the preoperative culture in preventing SSI needs to be investigated in the future. In conclusion, physicians should keep in mind that although surgical resection can improve the symptoms and abnormal values in laboratory examination form MW, it is accompanied with a high rate of SSI and poor prognosis.