I’m not a microbiologist, but this is the info I was able to find.
If my understanding is correct, cervical cancer arises within the “transformation zone” between the squamous and glandular cells of the cervix. However, the squamous cells are where abnormalities (e.g. cancer) often occur. So we’ll go with that.
The average diameter of the intermediate squamous cell is 1,437 micrometers. Assuming the cells are circular, this roughly converts to an area of 1,621,822.9 square micrometers (or 1.62~ m2). The cancer cell size would vary, since they can be either smaller or larger than its non-cancerous counterpart.
The surface area of Earth is 196.6 million mi2. This converts to 316,879,833,600 m2.
I don’t know how big the tumor in question is, so we’ll start with one cancer cell. If this 1.62~ m2 cancer cell doubles in size every 20 hours, it would take roughly 350 hours (14 days, 14 hours) to cover the Earth. If the cells double in size every 24 hours, it would take *roughly 420 hours (17 days, 12 hours) to cover the Earth.**
TL;DR: If my math is even near correct, it would take about 14-18 days to cover the Earth.