I'm looking for some book suggestions on oncology, preferably I want them to be fairly recent. I am not worried if they are fairly technical, as long as they have good accurate content and layout.
You could try DeVita, Hellman, and Rosenberg's Cancer: Principles & Practice of Oncology. It has detailed information on both biological and clinical aspects of cancer. Apparently, the publishers regularly release online updates to cover the latest developments in oncology.
Reference to the current edition:
DeVita VT, Rosenberg SA, Lawrence TS, editors. DeVita, Hellman, and Rosenberg's cancer: principles & practice of oncology. 11th Edition. Philadelphia: Wolters Kluwer; 2018. 2432 p.
The must-have textbook: The Biology of Cancer from Robert Weinberg
https://www.routledge.com/The-Biology-of-Cancer/Weinberg-Weinberg/p/book/9780429258794
The Second Edition was published in 2013, I didn't heard about a newer Edition yet but the current one is well recognized in the field