Clinic visit today - discussion on pathology results

Tighe had a check-up at the clinic today and we got to ask Dr. Twist some more questions about the pathology report and Tighe's prognosis. I'll give the update in question/answer format.

Q1: What percentage of the removed tumor still had active Neuroblastoma cells?
A1: About a third. But these active neuroblastoma cells now look different to the original cells from the biopsy back in December. They are starting to take on the characteristics of what we term "differentied cells." Differentiated cells are the ones that start looking more like regular nerve cells; these are deemed not to be dangerous. However we did characterize this one third of remaining cells to be neurblastoma because they still had some "immature features." They are less aggressive than the original neurblastoma cells from the December biopsy, and are less likely to grow again. --Dr. Twist reiterated her estimation of less than 20% chance of regrowth.

Q2: Did you look at the cross-section of the tumor where it was cut at the point it entered Tighe's spinal column, and hence were you able to make a better determination of what those remaining cells might look like?
A2: No, we were not able to do that. In some cases we can, but not in this case. Because of the way the tumor was removed, scooped and folded etc, it's not possible to determine where it was cut away from what we had to leave in there.

Q3: Do you know what the blood supply to what remains looks like?
A3: Not exactly. Certainly there's not any major blood vessel supplying the remaining tumor. It'll mostly be localized capillaries. The blood supply in that part of the body is quite good though, so we can't say that the tumor will not grow because it will be starved of blood.

Q4: If the remaining tumor began to grow again, at what rate might it grow across the spinal column? Are you confident that an MRI scan every two months is adequate?
A4: If anything I think two months is a bit aggressive, we are being very conservative here. If it starts to grow again I'm confident we'll catch it before it does Tighe any harm.

Q5: If it grows again, are there increased chances of it metastisizing (i.e. spreading to other parts of Tighe's body)?
A5: No. There's less than a 20% chance of it growing again, but if it did grow, there's less than a 5% chance of it metastisizing (i.e. overall less than a 1 in 100 chance that Tighe will have to deal with this metastisizing).

Q6: I remember reading at some point that if neuroblastoma recurs, then automatically the patient is elevated to Stage IV High Risk. And with that comes a much more severe treatment regimen?
A6: No. The Staging in this case is only relevent to the original diagnosis. If the tumor inside Tighe regrows it will most likley still be localized and not High Risk. We would probably use a stronger chemotherapy to treat it, but it is not equivalent to what we would use for a Stage IV High Risk patient. And if it does regrow, we will assess what the treatment might be then, it could be chemo or surgery.

Q7: Will we do another MIBG scan? Especially in the case where we feel that all the neuroblastoma cells are gone, would this be a final verification? (This is the test where they inject into Tighe a substance that attaches itself to Neuroblastoma Cells which then show up on a Cat scan).
A7: At some point in the future we will do this. However, after chemotherapy treatment this test does not work as well. But there will be times in the future when we do this as part of the overall testing to ensure it's gone and not coming back.