The question is why would our system leave a package(cyst), as you describe, in the system. Normally the system deals with extra unwanted or unneeded components in the same way a house holder would deal with either a bag of kitchen refuse or a bag of yard material gathered after working outside. The one that is more quickly susceptible to breakdown would be disposed of sooner than the one that is less prone to "oxidation", like old concrete or rocks or wood cuttings. One is removed quickly, the other may be allowed to stay put, out of the way. Each determination and procedure would be affected by the health and the available energy of the participating system. If the householder is too old and weak or young but infirm, both things may become problematic and the problem only becomes acute depending on the nature of the different bags contents or in the addition of bags accumulating. Our systems respond similarly whether its the cleansing ability of the lymphatic system or the reproduction ability of each cell. If our energy is adequate, the systems functions are adequate. If not, for some reason, places of subpar function result, will be acquired and potentially accumulate.
If we fast or if the householder goes on a very long hiatus from work or retires, he might, as our body systems should, in that freed from work distraction, peruse the overall status of the system and do any needed upkeep and cleaning that had been neglected or considered unnecessary.
If the cyst you describe is a regular fluid or somewhat fluidic cyst then sure we might expect it to have been autolyzed on a 30 day fast, tho since it didn't happen, we might consider that the cyst is too isolated from the systems at play, normal kidney and kidney cells functions, involving the blood and the lymphatic systems cells and actions, by a membrane or by the state of the area, where it is being isolated from normal fluid circulation. (like a bag of old tree twigs lying covered over by something in a back corner of the yard or left inadvertently in a shed, unseen).
Or it may be that the situation is compromised in both examples, from achieving normal actions by a lower running voltage, thus a weakened state, a chronic fatigue has set in, and thus the cells involved normally expected actions and reactions would be dampened and subpar in performing their expected activities.
Determining the present running voltage of a subpar system aids the diagnosis and possible treatment protocol. If we cant determine that we can still add energy to the subpar running system while we are also investigating other alternative possibilities and are making sure of the basic environmental integrity of the overall systems being influenced by outside or hidden inner negative factors(infections), or the loss of or lack of raw materials. However the main thrust of this analogy is that low energy is the main reason why any system eventually becomes noticed as being subpar and while certain factors may need to be corrected before others. By first adding energy, we prime and boost the system back to some semblance of normal functioning and away from it's present lack of necessary healthy functioning.
So adding Voltage or a helper in the case of the octogenarian, is a good idea in any case.
Earthing as mentioned may be the lest expensive unless we actually go hog wild and buy some of the advertised accoutrements. Daily or nightly routines might be established using any number of simple tecniques, from Archus'es lying on a field, or being covered in earth(daily for hours), to attaching a complete circuit connection from earth to our body. Tho the time element is to be considered for the length of treating ease and how long the treatments will need to be done until we notice a response (kinda tough if we are dealing with a serious condition,) (Tennant has patients attach skin patches and carry his voltage inducing unit around 24 hrs a day till the circuit in question returns to expectations.(Ive worn mine for hours at a time).
I still like the micro current devices advertised on that less expensive site, or the PEMF units, tho the addition of using Tennants Biomodulator to check the field strength at the different body meridians is best (some hospitals use a machine to do the same. cant remember the name off hand maybe Nakatoni something).
Also DMSO's carrying ability added to Tincture of Cayenne's burn mimicking, fluid drawing actions, are also a simple inexpensive treatment(to be carried on for a time tho, like fasting or castor oil packs as most of the alternative, as opposed to Allopathic, treatments, need to be done).
Surgicly removing a 2cm cyst seems like minor Operation (tho its only minor when its happening to someone else) tho the kidney is delicate and complex of course and scarring avoidance is part of why the non surgical route is preferred. And correcting or at least determining the causation is an important step often ignored or missed by 'regular' medicine.
First Iodine, second or also first, Voltage.
Tho another excellent supplement, along with the Iodine supps, is the DMSO derivative, organic sulfer, MSM. It not only plays an important role as a constituent of a cell membrane's makeup and permeability but it will hook up with numerous substances in our system which we would like removed but are difficult to chelate out(creating a sulfide, with which the body cannot abide, so it is put, like the kitchen trash, outside). MSM should not be taken in pill form and the amount I take is 2 teaspoons to 2 tablespoons a day. It has some remarkable properties, is always good to take and especially if we are trying to correct some situation.
(and C Dickens mother said, "If you are bored, there's a short story contest in the newspaper today.")