Docs: added custom arguments example in README [no ci]

README.md

@@ -33,8 +33,14 @@ lungtumormask input_file output_file
 
 # Example
 lungtumormask patient_01.nii.gz mask_01.nii.gz
+
+# Custom arguments
+lungtumormask patient_01.nii.gz mask_01.nii.gz --lung-filter --threshold 0.3 --radius 3
 ```
 
+In the last example, we filter tumor candidates outside the lungs, use a lower probability threshold to boost recall, and use a morphological smoothing step
+to fill holes inside segmentations using a disk kernel of radius 3.
+
 ## [Citation](https://github.com/VemundFredriksen/LungTumorMask#citation)
 If you found this repository useful in your study, please, cite the following paper:
 ```