Hello! Yes, your concern is very true.
This distension can be due to obstruction in intestines or also as very correctly mentioned by you, due to some tumour.
In females, commonly ovarian tumour is the culprit for big distension of abdomen.
In my clinic, many such patients do come to whom I advise,
ultrasound abdomen & pelvis, urine & stool routine, CBC.
Treatment is done accordingly.
It is advisable to get an ultrasound done before you fly, as if its an obstruction in intestines (subacute), it may progress to complete (acute) obstruction, which is a medical emergency.
Hope this information is useful.
Wish you a good health.
Thanks. Regards.