Patients' Perspectives

# Table showing doubling time of cancer cells

In the first column of the table below, the doubling time of cancer cells is set to a relatively "short" period of time, 60 days, and the number of cells present after 3600 days (nearly 10 years) is shown at the far right.

In the second column, the doubling time of cancer cells is set to a relatively "average" period of time, 100 days, and the number of cells present after 6000 days (a little more than 16 years) is shown, again in the column on the far right.

The third column shows the number of cells present as each doubling time is reached. In case the reason that the numbers in the third column are accurate for both doubling times, it may be easier for you to think of the doubling periods as making a new "generation" of tumor cells, such that for a given number of doubling times, the number of cells will be the same. However, if you take the number of days on one line of the table, for example, at the 39th level of doubling, you find 2340 days for the rapid doubling period to result in that number of cells whereas at the slower rate it takes 3900 days.

In both cases, the number of generations of doubling is 60. The point being illustrated here is that a tumor called "aggressive" will be detected by either clinical examination or scans sooner than a tumor that is not termed aggressive because the aggressive tumor will grow more quickly than the tumor that is not considered aggressive. How much faster cannot be determined, only that it is relatively faster.

The style of notation in the numbers below is called "exponential notation". To determine the value of these numbers as most of us are used to reading them, move the decimal point as many places to the right as the number after the E on the appropriate line. If there are not enough digits, add zeroes to the right hand end of the number to make enough digits to move the decimal to the correct number of digits and dump the E+ and the number to the right.

## 60 and 100 day tumor doubling time

 Doubling every 60 daysbeginning with 1 cell(aggressive) Doubling every 100 daysbeginning with 1 cell(not so aggressive) Number of cells Days of doubling = 60. Days of doubling = 100. 1st level of doubling = 2 Days of doubling = 120. Days of doubling = 200. 2nd level of doubling = 4 Days of doubling = 180. Days of doubling = 300. 3th level of doubling = 8 Days of doubling = 240. Days of doubling = 400. 4th level of doubling = 16 Days of doubling = 300. Days of doubling = 500. 5th level of doubling = 32 Days of doubling = 360. Days of doubling = 600. 6th level of doubling = 64 Days of doubling = 420. Days of doubling = 700. 7th level of doubling = 128 Days of doubling = 480. Days of doubling = 800. 8th level of doubling = 256 Days of doubling = 540. Days of doubling = 900. 9th level of doubling = 512 Days of doubling = 600. Days of doubling = 1000. 10th level of doubling = 1024 Days of doubling = 660. Days of doubling = 1100. 11th level of doubling = 2048 Days of doubling = 720. Days of doubling = 1200. 12th level of doubling = 4096 Days of doubling = 780. Days of doubling = 1300. 13th level of doubling = 8192 Days of doubling = 840. Days of doubling = 1400. 14th level of doubling = 16384 Days of doubling = 900. Days of doubling = 1500. 15th level of doubling = 32768 Days of doubling = 960. Days of doubling = 1600. 16th level of doubling = 65536 Days of doubling = 1020. Days of doubling = 1700. 17th level of doubling = 131072 Days of doubling = 1080. Days of doubling = 1800. 18th level of doubling = 262144 Days of doubling = 1140. Days of doubling = 1900. 19th level of doubling = 524288 Days of doubling = 1200. Days of doubling = 2000. 20th level of doubling = 1048576 Days of doubling = 1260. Days of doubling = 2100. 21th level of doubling = 2097152 Days of doubling = 1320. Days of doubling = 2200. 22th level of doubling = 4194304 Days of doubling = 1380. Days of doubling = 2300. 23th level of doubling = 8388608 Days of doubling = 1440. Days of doubling = 2400. 24th level of doubling = 16777216 Days of doubling = 1500. Days of doubling = 2500. 25th level of doubling = 33554432 Days of doubling = 1560. Days of doubling = 2600. 26th level of doubling = 67108864 Days of doubling = 1620. Days of doubling = 2700. 27th level of doubling = 134217728 Days of doubling = 1680. Days of doubling = 2800. 28th level of doubling = 268435456 Days of doubling = 1740. Days of doubling = 2900. 29th level of doubling = 536870912 Days of doubling = 1800. Days of doubling = 3000. 30th level of doubling = 1.07374182E+9 Days of doubling = 1860. Days of doubling = 3100. 31th level of doubling = 2.14748364E+9 Days of doubling = 1920. Days of doubling = 3200. 32th level of doubling = 4.29496728E+9 Days of doubling = 1980. Days of doubling = 3300. 33th level of doubling = 8.58993456E+9 Days of doubling = 2040. Days of doubling = 3400. 34th level of doubling = 1.71798691E+10 Days of doubling = 2100. Days of doubling = 3500. 35th level of doubling = 3.43597382E+10 Days of doubling = 2160. Days of doubling = 3600. 36th level of doubling = 6.87194764E+10 Days of doubling = 2220. Days of doubling = 3700. 37th level of doubling = 1.37438953E+11 Days of doubling = 2280. Days of doubling = 3800. 38th level of doubling = 2.74877906E+11 Days of doubling = 2340. Days of doubling = 3900. 39th level of doubling = 5.49755812E+11 Days of doubling = 2400. Days of doubling = 4000. 40th level of doubling = 1.09951162E+12 Days of doubling = 2460. Days of doubling = 4100. 41th level of doubling = 2.19902324E+12 Days of doubling = 2520. Days of doubling = 4200. 42th level of doubling = 4.39804648E+12 Days of doubling = 2580. Days of doubling = 4300. 43th level of doubling = 8.79609296E+12 Days of doubling = 2640. Days of doubling = 4400. 44th level of doubling = 1.75921859E+13 Days of doubling = 2700. Days of doubling = 4500. 45th level of doubling = 3.51843718E+13 Days of doubling = 2760. Days of doubling = 4600. 46th level of doubling = 7.03687436E+13 Days of doubling = 2820. Days of doubling = 4700. 47th level of doubling = 1.40737487E+14 Days of doubling = 2880. Days of doubling = 4800. 48th level of doubling = 2.81474974E+14 Days of doubling = 2940. Days of doubling = 4900. 49th level of doubling = 5.62949948E+14 Days of doubling = 3000. Days of doubling = 5000. 50th level of doubling = 1.12589990E+15 Days of doubling = 3060. Days of doubling = 5100. 51th level of doubling = 2.25179980E+15 Days of doubling = 3120. Days of doubling = 5200. 52th level of doubling = 4.50359960E+15 Days of doubling = 3180. Days of doubling = 5300. 53th level of doubling = 9.00719920E+15 Days of doubling = 3240. Days of doubling = 5400. 54th level of doubling = 1.80143984E+16 Days of doubling = 3300. Days of doubling = 5500. 55th level of doubling = 3.60287968E+16 Days of doubling = 3360. Days of doubling = 5600. 56th level of doubling = 7.20575936E+16 Days of doubling = 3420. Days of doubling = 5700. 57th level of doubling = 1.44115187E+17 Days of doubling = 3480. Days of doubling = 5800. 58th level of doubling = 2.88230374E+17 Days of doubling = 3540. Days of doubling = 5900. 59th level of doubling = 5.76460748E+17 Days of doubling = 3600. Days of doubling = 6000. 60th level of doubling = 1.15292150E+18