Leukemia Management in RadOnc

[Palex80]

Ok I have a question:

What is the general management in your clinic for chloroma / myeloid sarcoma and CNS involvement?


Case 1:
Patient is diagnosed with AML. MRI scans reveal epidural involvement Th5-Th9. Patient shows no neurologic symptoms, CSF is negative. He receives high dose induction chemotherapy for 2 cycles with intrathecal chemotherapy prophylaxis. Follow up MRIs show epidural CR and bone marrow shows CR.
Patient is scheduled thus for allogeneic stem cell transplantation, conditioning is scheduled to include TBI 12 Gy (6x2Gy).
Would you treat this patient more aggressively (for example TBI 6x2 Gy + upfront TH5-9)? To what doses?


Case 2:
Patient diagnosed with ALL. CSF is positive, cranial MRI reveals dural enhancement, without any larger lesions. Patient shows no neurologic symptoms. He receives induction chemotherapy, including intrathecal chemotherapy. Follow up MRIs show epidural CR, CSF and bone marrow shows CR.
Patient is scheduled thus for allogeneic stem cell transplantation, conditioning is scheduled to include TBI 12 Gy (6x2Gy).
Would you treat this patient more aggressively (for example TBI 6x2 Gy + upfront CSI or only WBRT)? To what doses?

There is some evidence out there for more aggressive CNS treatment i high risk patients, but most of the studies conducted are on children.
A very interesting German study showed that treating mediastinal bulk lesions in children with ALL did not improve prognosis. This has led many physicians to abandoning local radiation therapy for childdren with chloromas from ALL. However I am not sure if the same results can be extrapolated to older patients.
Children have excellent prognosis with ALL. 90%+ survive ALL, so the potential benefits of thoracic irradiation would have to be quite high in order to show a true benefit, because the margin for bettering the outcome are quite small.
On the other hand patients elder than 18-20, show a worse prognosis when diagnosed with ALL. Perhaps in these patients, local chloroma radiation treatment may enhance prognosis.

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[Palex80]

No ideas?

 

[radonc]

No ideas?

here is what i put together for cns rt in pediatric leukemic patients, mainly based of st jude recs and textbooks:


1) CNS prophylaxis in high risk patients with CSF- (unless pt underwent a bloody tap)
2) CSF+ or cranial neuropathy
2) CNS relapse, no prior RT: no transplant planned
3)CNS relapse, no prior RT: transplant planned

High risk:
Age <1 or >10
WBC>50K
T-cell histology

 

[Palex80]

here is what i put together for cns rt in pediatric leukemic patients, mainly based of st jude recs and textbooks:


1) CNS prophylaxis in high risk patients with CSF- (unless pt underwent a bloody tap)
2) CSF+ or cranial neuropathy
2) CNS relapse, no prior RT: no transplant planned
3)CNS relapse, no prior RT: transplant planned

High risk:
Age <1 or >10
WBC>50K
T-cell histology

Thanx for your input. I am familiar with these recommendations for children, although I am quite skeptic concerning the implications of delivering neural axis radiation therapy in kids, because of risk for late sequlae. Several protocols avoid neural axis radiation therapy and favor intrathecal chemotherapy instead. We generally only give WBRT in children with ALL:

I guess my questions are way too specific and rather case-by-case decisions.

 

[Raygun77]

Thanx for your input. I am familiar with these recommendations for children, although I am quite skeptic concerning the implications of delivering neural axis radiation therapy in kids, because of risk for late sequlae. Several protocols avoid neural axis radiation therapy and favor intrathecal chemotherapy instead. We generally only give WBRT in children with ALL:

I guess my questions are way too specific and rather case-by-case decisions.

Any evidence of intra-thecal chemo having significant late sequlae? It's still cytotoxic after all.

I don't know much about WBRT (or rad onc in general, heh), but would adding more fractions to increase the total dose of radiation be an option? Say 2x8 or something, just to be sure you've cleared all the bone marrow out. Is that the primary concern- that some microscopic cancer cells may still be seeding the bone marrow, and thus cause a cancer recurrence?