Yes. I agree with the above posts. What you are experiencing either seems to be a fungal infection of some sort which is caused by poor water quality and stress, or a tumor
Fungal Disease Information
There are numerous reasons for tumors in fish and tumors are by themselves not to be considered as diseases or even negative even though they can have negative esthetical effects on the fish that gets them. This does however not mean that a tumor can't be a problem; they can be signs of very dangerous diseases. It just means that tumors aren't necessary a problem or a sign thereof. Tumours can for instance be caused by the thing most of us think about when we hear the word tumour – cancer. Cancer aren't common in most tropical aquarium fish as they are relatively short lived and cancer only rarely have time to develop and become a problem before the fish dies of age. This does however not mean that it never happens. Cancer is more likely and can be a bigger problem in more long living fish species. Sharks don't get cancer and you can therefore rule out cancer if one of your (true) sharks develops a tumor. Some researchers actually hope that sharks will reveal the secret to preventing and curing cancer in humans as well.
Tumors in fish can also be due to virus that has infected the fish. The bulk of all tumors found in fish are however result of genetic traits in that fish and hence not dangerous or a sign of problem. It is possible to surgical remove tumors that are unattractive or that causes problems such for the fish, such as problems eating. You will need a hospital tank for recovery, a scalpel, antibiotics and anaesthesia if you want to try this. I will however not write more about it in this text and I recommend that you obtain more information before trying it, or even better – hire someone with experience to do it for you. I would also recommend that you check the local rules surrounding the keeping of fish and animal cruelty to see if you are allowed to perform such operations yourself in the area you live in.
White, or fuzzy growths on the outside of fish
Fish has become less active
Patches of white
This disease is very common with stressed fish and is cured with Higher levels of added salt, easing the temperature within the tank to 80 will also help. But no higher than 82. If the disease progresses then invest in a high quality fungus treatment to help aid the treatment, if that doesn't work then I highly suggest that you either euthanize the fish or heavily Medicate, sterilize, and heat the temp even higher within the tank
There are many factors to what causes this specific disease but it's similar to many others.
-poor water quality, like high ammonia, and nitrites along with unecxeptable Amounts of nitrates
-stressful tankmates and constant nipping
-being battered around by flow
-not acclimated properly
Are all main factors to the disease as they all lead to a lored immune system which leaves all fish helpless towards all diseases
-keep water clean
-keep the stress to minimal amounts
-keep water heated
-choose acceptable tank mates
-provide enough cover
-give your Betta enough room to swim and spread its fins. Ideally 2.5 gallons