Treatment


Most all T-cell patients will get put on a high-risk chemotherapy protocol which most likely includes cranial radiation at 1800cgy. Some may still be put on a standard risk protocol but that is changing as new data comes in. At the moment what protocol a kid is put on usually depends on which oncology group the particular hospital belongs to. Even though the two oncology groups, Pediatric Oncology Group (POG) and Children's Cancer Group (CCG), have recently merged into one called Children's Oncology Group (COG), the protocols so far have not, so kids are put on either a POG protocol or CCG protocol. Stanford is a POG hospital so Spencer was put on POG 9404, which is primarily a T-cell specific regiment. The strongest CCG T-cell protocol is CCG 1961, which is a modified B-cell protocol. If we had opted to go south (a coin flip) to Children's of LA we would have been on CCG 1961.

POG 9404 is a fairly uncomplicated but intense protocol consisting of three stages. First is a 6 week Induction period that includes two large chemo rounds, a couple spinal taps (aka lumbar punctures - LPs, or intrathecals - ITs), and an extra hit of doxorubicin in the second week. There is also a 21 day pulse of steroids. The drugs involved are doxorubicin, vincristine, methotrexate, prednisone, mercatopurine (6mp), and ara-C, among others. At days 22 and 44 a bone marrow aspirate is done to monitor the progress. If the bone marrow is clear at day 44 you are in remission and can proceed to the next phase. Spencer's bone marrow was clear at day 22, which was an excellent response given his high presenting white count. Much of this phase is done in-patient, particularly in the beginning because often times the patient is sick, and the white count can get dangerously low.

The second phase is called Consolidation and lasts 6 months. It consists of large chemo rounds, which are much the same as during Induction, every three weeks (white count dependent), and weekly L-aspariginase shots for 20 weeks. These are intramuscular shots given one in each thigh (40 shots total). The second round during Induction and the first four rounds in Consolidation contain high-dose methotrexate, which requires a 5-6 day inpatient treatment. The rest can normally be done outpatient. Radiation therapy happens during Consolidation and is scheduled to start on week 22 (from diagnosis) and lasts two weeks. There are also 2-3 LPs. Spencer finished all the high-dose methotrexate, 16 of 20 shots, had only 3 large rounds left, and was scheduled to start radiation three days later when he was diagnosed as having relapsed in his central nervous system, when the protocol was discontinued.

Had we continued on this course, at the end of Consolidation we would have started the third and longest phase, Continuation chemotherapy (aka Maintenance). This lasts through the end of 104 weeks, not counting delays. It still contains larger chemo rounds every three weeks of vincristine, methotrexate (not high dose), prednisone, and 6mp. There is also IV methotrexate each week. And there are 5 LPs during this phase. These chemo rounds are not as intense as during Consolidation.

Because there is so much IV medications and so many blood draws through treatment a patient has a catheter put in, which is a tube that goes under the skin on the chest directly into a large vein leading to the heart. Stanford normally puts in a double lumen Hickman catheter so two things can be going on at once, like chemo and IV fluids. There is a lot of maintenance and lifestyle changes involved with a Hickman, such as daily flushing, changing the caps twice weekly, and dressing changes. Dressing changes normally are once a week, but because of Spencer's sensitivity to adhesives we had to do it every other day. This is critically important to prevent infection, after all, it is an open avenue directly to the heart. Spencer's Hickman essentially broke down (not uncommon) after 3 1/2 months and had to be replaced. As we were finished with the high-dose methotrexate and all planned hospital stays we opted to replace it with a mediport, which is a single lumen port that is under the skin and has to be accessed with a needle. Ports are useful when the drugs and blood draws become less frequent. They have less risk of infection and you can take a bath and go swimming with them. They are essentially invisible and don't cramp your lifestyle. However, accessing them is a bitch. Spencer's port will not be used, and likely will be removed for his transplant. Another Hickman will have to be put in. All these are put in surgically under general anesthesia.

Since Spencer relapsed, it possibly showed that his leukemia cells had a certain amount of resistance to chemotherapy. Data for T-cell shows that an isolated relapse in the central nervous system (CNS) often leads to a relapse in the bone marrow as well if not treated by other means besides chemotherapy. Currently the best option is a stem cell transplant of some sort. A stem cell transplant can be either a bone marrow transplant or an umbilical cord blood transplant, from either a related or unrelated donor depending on what's available. Both achieve the same thing, although there are significant differences between the two. The idea behind the transplant is, that since the body's immune system cannot identify and kill leukemic cells (since they are the body's own cells anyway), a new immune system is necessary. If all goes well this new immune system will recognize the leukemic cells as foreign and attack and kill them (graft vs. leukemia). After a transplant there is no more chemotherapy. See the page about transplant to read more about this.