First and foremost it is important to have confidence in your oncologist , but make sure you have a MM Specialist if possible on your healthcare team to collaborate with local treatment.
The question you pose is really specific to your case, not being evasive. How many blood tests have been taken in total and how many blood tests have shown the trend , how far out of range, how often are tests taken, and the degree of magnitude of test changes is important too. Statistically there are variation , range, and repeatability to consider. These are the topics of discussion you should have with your oncologist who should be familiar with your case. I would recommend that you make a list of these concerns before your next appointment. Hopefully fairly soon to make you comfortable. If your next appointment is not soon enough ask for an appointment to discuss the specifics if possible. Another avenue is to speak with your doctors oncology nurse if there is one on your team.I am fortunate to have a very qualified oncology nurse to discuss issues as well. She helps me with medication side effects and my lab result interpretations. Multiple myeloma is called “multiple “ because there are so many types and complexities so hang in there and ask for professional interpretation. I hope this helps remove some emotion and stress ,and add a little technical perspective. We can go through this before or after each lab test rounds ,and often when the roller coaster of MM or med side effects toss us for a loop. I certainly do too. Do we panic at times, yep. MM is complex and can be insidious. I hope you get answers to help you through. 🙏

Mepapermaker1 is right. Multiple myeloma occurs 8n many forms and many places. Depending on what mutations are involved in your particular form of myeloma, each indicator will have different significance. M-spike is really important in some cases; in mine it is not so important. Also, my oncologist assures me it is trends in readings that matter more. My light chain readings are more significant, according to my Mayo Clinic doctor, (the head of hematology, so I trust her to know what she's talking about). Luckily for me, all those readings have been "so low as to be immeasurable since November 25, 2020, when I was declared to be in remission the second time. My M-spike was .01 and my kappa light chain reading was "trace." By contrast, my M-Spike reading was 5.6 that September, and the kappa light chain reading was 10.7. my local oncologist had noticed a definite increase in both those readings in July and a steeper increase in August, after my remission in February due to a SCT.

You deserve answers to your questions. I hope you can communicate to your doctor as soon as possible, even if you don't have an appointment for awhile.

Lots of good advice. I know my Dr really watches my M spike and so do I. I think the main things are trust and communication. Your questions are good and relevant and should be explained. My oncologist doesn’t chit chat but gives me the info and answers questions so I understand. I hope your oncologist gains your trust and answers questions or maybe it’s time to find a new one.

I find most will call you if there is any concern in your blood. I often state that patient will get hung up on the numbers. IgG is the bodies Army, that response to infections and is the protector of a patient immune response. Many variables may contribute to a fluctuation in IgG levels medication, vaccines, underlying conditions. I don't sweat the
numbers, when it comes to bloodwork or my free light chain, IgA, IgM, etc. After 9 years of blood work at least every 3 months I've experienced fluctuations. A little bit of knowledge can be dangerous. I've never meet a doctor who didn't have a staff member reach out if there was a serious issue. I was born without a complete immune system and have very low IgG. As I write this post, I'm giving myself a sub-q infusion of IgG, something I do every week. Honestly I know my body, I know the Infusion will fluctuate my IgG. IgA, RBC etc. Your Doctor will weigh the benefit of medications and any fluctuation in your level for end goal. I don't reach out to laymen for an opinion' or suggestion. If my car was acting up I would call pest control specialist to do diagnostics for my car. I've seen 7 Hematologist in 9 years. A second opinion maybe a wise choice, If you feel your doctor isn't addressing your concerns.

IgG raising could also be due to vaccination. Your body responding to the vaccination building antibodies. Typically you will see a rise in IgM, followed by a rise in IgG after getting vaccinated. IgM is first line defense, IgG long term defense. What are your IgM results? Did you recently get vaccinated? Mepapermaker1 is correct, there are so many types and variations, that you have to look at a number of tests and results to draw a conclusion. In my case, I have no M spike at all, which only occurs in 1-5% of MM patients. My IgA and IgG are at the low end of normal. My IgM is super low, and my light chain ratio is in the normal range. In my case my light chain ratio is very important.