Undifferentiated sarcoma of the liver: Multicenter international experience of the Cooperative Soft‐Tissue Sarcoma Group and Polish Paediatric Solid Tumor Group

Abstract

Background: Undifferentiated embryonal sarcomas of the liver (UESL) are extremely rare and continue to pose a diagnostic and therapeutic challenge. The aim of the study was to present a multicenter experience of the German CWS and Polish PPSTG groups in the treatment of UESL in children. Procedure: Twenty-five patients were treated according to the CWS-96, CWS-2002, and CYVADIC protocols. Distant metastases were observed in four cases (16%). In four cases, an initial disease presentation mimicked other entities. A pure cystic appearance of liver mass led to misdiagnosis of hydatid cyst in three cases. In one case, laparotomy was performed due to the signs of appendicitis, and bleeding from ruptured liver tumor was found. All these patients were finally diagnosed as UESL. Results: Thirteen patients received preoperative chemotherapy. Partial response was observed in 10 cases. Tumor resection was performed in 20 patients (primary resections, 12; delayed resections-, 8). In five patients, the primary tumor never became operable. The macroscopically complete resection rate was 95% (19/20). Postoperative chemotherapy was given to 20 children. Local radiotherapy was used in three children. After a median follow-up time of 136 months, 17 patients (68%) were alive with no evidence of disease. All children with unresectable tumor and three out of four patients with distant metastases died. The five-year overall survival (OS) rate was 72%. Conclusions: In summary, a complete tumor excision plays the central role in the treatment of UESL. A cystic presentation of the liver lesion on imaging does not exclude the diagnosis of malignant tumor.

Surgical perspective on treatment of pediatric undifferentiated sarcoma of the liver

“…But still, and as mentioned above, the management for UESL varies within different oncological societies, as further addressed below [Table 1]. Nonetheless, the general agreement is as follows: if the mass is resectable, an upfront surgical resection followed by adjuvant chemotherapy is advised; however, if the mass is deemed an unresectable mass, a neoadjuvant chemotherapy, reassessment, surgical resection or liver transplantation, and subsequent chemotherapy is recommended [Figure 1] [9,10] .…”

“…The German CWS (Cooperative Weichteilsarkom Studie) also evaluates treatment response after 3 courses of chemotherapy, and if deemed feasible a definitive delayed surgery is performed after the 4th course; within both protocols, abdominal irradiation is recommended only if local control cannot be achieved otherwise [11] . The American Children Oncology Group (COG) uses different protocols; within the "soft tissue sarcoma protocol", 5 courses of neoadjuvant chemotherapy are employed [10] .…”

“…The surgical challenges in the treatment of UESL are mainly related to the large size at the moment of diagnosis [10] . Fortunately, initial aggressive surgeries are less required nowadays, since, as stated above, neoadjuvant chemotherapy decreases tumor size and makes it more amenable to a more standard complete resection [20,21] .…”

Identification of a TP53 Deletion in an Undifferentiated Embryonal Sarcoma of the Liver Provides Clinically Relevant Longitudinal Detection of Circulating Tumor DNA

“…2 Advances in management of these tumors including surgical resection, with or without liver transplantation, along with adjuvant high-dose alkylator-and anthracycline-based chemotherapy provides a curative outcome in the majority of cases. 1,[3][4][5][6][7] Although there is no universally accepted treatment, the systemic approach is generally similar to that of other soft tissue sarcomas. [3][4][5]7 Notably, a recent pooled analysis of UESL demonstrated a 5-year overall survival of 70% for those who were able to undergo surgical resection.…”

“…1,[3][4][5][6][7] Although there is no universally accepted treatment, the systemic approach is generally similar to that of other soft tissue sarcomas. [3][4][5]7 Notably, a recent pooled analysis of UESL demonstrated a 5-year overall survival of 70% for those who were able to undergo surgical resection. 6 When UESL arises in the context of a mesenchymal hamartoma, an otherwise benign liver mass, the tumor generally contains a t(11;19) (q13;q13.4) fusion.…”