Brief Answer:
Chronic gastroenteritis.

Detailed Answer:
Hello Dear,
Thank you for choosing HealthcareMagic for your query.
I am Dr. Kumar a Gastroenterologist and would be addressing your query.
Before answering your question let me give you a briefing about the problem you are suffering from this will help you understand things better.

You are suffering from an ailment called Gastroenteritis. It's also commonly referred to as infectious diarrhea, and is a gastric disorder. The gastrointestinal tract, which comprises of the small intestine and stomach gets inflamed. Gastroenteritis is indicated by the symptoms such as diarrhea, and pain in the abdomen with formation of excessive gases(making rumbling sound). Fever, exhaustion and dehydration are also observed.However its not necessary that all symptoms are there in every patient. This disease usually lasts not more than two weeks.It is also called the stomach flu. Infections caused by virus, bacteria, parasites or fungi may lead to gastroenteritis. Viruses account for this disease the most. This disease is transmitted mainly from food items and contaminated water. Important electrolytes like sodium and potassium are lost from our body.The most common remedy in case of gastroenteritis is having electrolyte solution and keep yourself hydrated.

Treatment.
Due to the toxins produced in the intestines the natural good bacterias present in gut are destroyed hence food will remain in intestines for long time and will be fermented by pathogenic bacterias leading to inflammation of intestines and production of large amount of gases.So the earlier you relpenish your lost gut flora the faster would be recovery.
I would suggest you to start taking probiotic(if VSL#3 is not helping shift to econorm daily.It contains good bacteria and would help to improve overall digestion of food.As digestion will improve production of excess gas will stop hence there would be no rumbling sound.
Along with probiotic take Nexium 20 mg with OTC antacid peptobismol twice daily.This will provide you with immediate symptomatic relief.
To stop loose stools take imodium 2mg stat dose followed by 2 to 4mg twice daily.
Take Fybrogel 2tsf daily with half cup of water.This is a fiber based product and would help in formation of bulky stools.

Apart from medication-
Take light vegetarian and easily digestible food.
Avoid spicy or fatty food.
Take lots of yoghurt and food rich in lactobacillus.
Drink lots of juices specially those rich in potassium.
Avoid alcohol or smoking.
No meat for atleast a week.

You will be fine in few days..

Suggestion
Get a stool routine and microscopy test done as in some case gastroenteritis is caused by bacteria and protozoa.
As in that case antibacterial and protozoal therapy will be given for 5 days.

As per your query regarding carcinoma symptoms of everything from mild gastroenteritis to malignant cancer in gut are almost same hence without investigations and rather examining the patient its very difficult to make a comment on it just on the basis of history.As you symptoms are recurrent detailed investigations like endoscopy colonoscopy and MRI abdomen have to be done initially to rule out possibility of malignanacy.
Hope i answered your query well.Feel free to follow up.

Regards.

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