February 25, 2014

We went to Moffitt Cancer Center yesterday to see the Doctor and plot a course of action for Evan.  The plan  is outlined below with a few pictures to assist.

The center is huge and treats all forms of cancer and is located on the campus of USF.  We were instructed to have the valet service park our car and to enter the lobby.  There Meghan needed to call the secretary on the unit we were to visit and we would be escorted to the clinic.  The escort was necessary as we would have been lost.

We discovered that  most of the humerus will need to be removed due to the large size of the tumor.  The entire head (ball) of the bone will need to be taken which will remove the growth plate at the top end of the bone.  The socket (glenoid) will be left intact and the bone will be removed to just above the elbow.  In X-rays of the arm comparing December and February, there is a marked difference in the tumor signature but only pathology will be able to tell how much of the tumor is necrotic (destroyed).  There has been no soft (muscle) tissue involvement as the tumor has not advanced outside of the bone and in fact the fracture caused the growth plate to lay new bone over the tumor site.  The picture below illustrates this.

Here are the options and how they were accepted or rejected:

Option 1 was to have Stanmore Implants create a titanium humerus with ball to be implanted in Evan.  A photo of the device is below.  This was rejected by the Doctor and eventually by us due to the fact that there is a significant weak point near the elbow.  The diameter and depth of the bone after removal of the tumor is small and the worry was that there would not be sufficient stability of the implant to bone and this could cause serious problems with additional fracture at the attachment site.  If you look at the bottom of the implant you will see an area that looks like an acorn seed.  The nub area is what would be implanted into the center of good bone above the elbow and the two wings would be wrapped around the bone and screws placed though the holes into the bone structure.  This is an excellent design for a bigger bone but not for a small one as the nub area is not very long.  The Doctors like to have a longer nub area for good adherence.  There is significant stress on this area and the potential for fracture, separation or the device to not heal properly  was a real concern.

Option 2 and the one we are going to go with is to have an allograft (cadaver bone) implanted after bone removal.  The university of Miami is providing an adult fibula to use on Evan.  The bone closely resembles a humerus and its length and diameter are close to the size needed.  It would be almost impossible to find a child humerus to use in this situation and we cannot wait for one to materialize as the tumor must be taken out.  The bone will be shaped to be like the titanium nub and will be placed in the center of the good bone just as above and they will use plates and screws to secure the implant.  The chance that Evan will begin to lay new bone over the allograft and cement a strong graft site is excellent due to his age and the growth plate working well.  The upper part of the graft will fit into the glenoid and be covered in gortex followed by the muscle layer.  This will in time give him the ability to move his arm freely but not completely overhead.

Evan is due to have to more rounds of Methotrexate starting this Thursday with the second round the following Thursday.  That will take us to March 10th with surgery scheduled later.  He will have a CT scan of his arm and lung for review before surgery.  The lung CT is especially important as they wish to make sure that the lungs are still clear of any signs of sarcoma.

As with all surgeries the risk for infection is present and is probably elevated due to his compromised immune system.  All the different scenarios to deal with infection were discussed and understood.  I will explain those later if he should develop one.  There is a good chance that there will be numbness in the arm because they must move nerves out of the way in order to remove and replace the bone but the Doctors feel this will be transient in nature; however the possibility of permanent numbness and damage exists.  The movement of the radial nerve is especially tricky as this nerve actually wraps around the humerus and needs to be gently coaxed away from the the bone.  His ability to flex his wrist will be compromised at first but the Doctor feels this too will go away after the radial nerve "settles" down from being moved.

The surgery will take place at All Childrens' in Saint Petersburg Florida which is adjacent to Tampa.  We have been there before with Ethan for outpatient surgery and know and like the place very much.  His surgery will be about 6 hours long and is to take place either 03/21 or 03/28 dependent on his white cell count.  He will be in hospital for about 6 days and then be released to go home.  Follow up appointment in Tampa will be scheduled for 2 weeks later.  His arm will be immobilized for quite some time to allow for the graft to adhere and new bone to be laid down.  After that he will need physical therapy to teach him to use his new arm.

The removed tumor will be analyzed by the pathology team for necrosis and the goal is to have at least 90% of the tumor to be destroyed.  If that is the case Evan will undergo another series of Chemo therapy with the same assortment of drugs he is currently taking.  If it is less then they will add a few more potent drugs to the mix to make sure that any cancer cells still in his body will be eradicated.

In time the allograft may need to be lengthened and that can be accomplished by adding a piece of new allograft.  The allograft may not take on new bone as expected and in time may become brittle and unstable.  If that happens then we would use the titanium rod as a replacement for the allograft.  The thought process on this is that the allograft will probably stay in place for at least 4 to 6 years which would place Evan at 8 to 10.  His natural arm just above the elbow would have grown significantly in length and girth during those years allowing for a stronger implantation of the rod that was not previously a reality. 

So this journey will be a long and steady one with the hope of increasing health and decreasing surgery and disease freedom.  I will be writing this blog until the day we are free of the cancer and the implant is a complete success.