AUTHOR=Szarvas Tibor , Reis Henning TITLE=Commentary: Treatment Outcome of Different Chemotherapy in Patients With Relapsed or Metastatic Malignant Urachal Tumor JOURNAL=Frontiers in Oncology VOLUME=Volume 12 - 2022 YEAR=2022 URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2022.864708 DOI=10.3389/fonc.2022.864708 ISSN=2234-943X