Brief Answer:
Fecal incontinence most likely

Detailed Answer:
Hi,
Thanks for asking the query,

Have noted all your details.
Most likely the problem you are having is Fecal incontinence.It is defined as inability to control bowel movements, causing feces to leak unexpectedly from the rectum.In your case its not complete but occassional. Diarrhea,muscle or nerve injury are the most common cause of it.
Investigations advice are-
Rectal examination by finger-finger is inserted in your rectum to evaluate the strength of your sphincter and rectal muscles and to check for any abnormalities in the rectal area.
Proctosigmoidoscopy- Sigmoid colon can be inspected to see signs of inflammation, tumors or scar tissue that may cause fecal incontinence.
Magnetic resonance imaging- MRI provide clear pictures of the sphincter to determine if the muscles are intact.
Defecography - is an X-Ray test that shows the rectum and anal canal as they change during defecation. This test is used to evaluate for disorders of the lower bowel that are not evident by tests such as colonoscopy or sigmoidoscopy.

Treatment-
Start doing Kegel exercise-Kegel exercises strengthen the pelvic floor muscles, which support the uterus, bladder, small intestine and rectum.
Dietery considerations are-
Eat a natural and simple diet.This should consist of unrefined food such as whole grain cereals, XXXXXXX honey and lentils; green leafy vegetables, like spinach, beans, lettuce, celery, asparagus, carrot.
Secondly human gastrointestinal tract is colonized by 1013-14 bacteria of 400 different species and subspecies.The good bacterias are responsible for proper digestion of food.Depletion of this flora due to chemotherapy and radiation therapy can lead to severe digestive problems.Keep on taking the probiotic you are on.
-Proper chewing: The diet alone is not enough. Food should be properly chewed-each morsel for at least 20 times.
-Taking a short walk is a good way to get some light exercise. Walking time should be gradually increased until it reaches 20 minutes.
-Fruits and vegetables, which contain high amounts of fiber,Whole-grain bread, XXXXXXX oatmeal, beans and lentils can also relieve the problem so use it Instead of highly processed rice, eat brown rice, millet or bulgur.
-Take Fybogel husk-Fybogel sachets and Fybogel Hi-Fibre sachets both contain the active ingredient ispaghula husk, which is a type of medicine called a bulk-forming laxative. Ispaghula is a type of fibre. It swells when it comes into contact with fluid in the gut and thus increases the volume of the faeces.It increases the bulk in your stool, an effect that helps to cause movement of the intestines.

Yes it is an alarming sign,all tests should be done to rule out the cause of the problem.

Follow up with reports,
Regards,
Dr.Kumar

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