Mednet Logo

What is your approach for bulky stage I primary mediastinal B-cell lymphoma in a patient with a positive post-chemotherapy PET-CT (residual mass and Deauville 5)?

Some specific questions: Would you recommend repeat biopsy to confirm residual disease? How would your recommendations vary if the patient had previously received intensive chemotherapy (eg. da-EPOCH-R) vs standard chemotherapy (eg. R-CHOP)? Should 2nd line chemotherapy and/or transplant be considered if biopsy is positive? Or should the patient proceed to ISRT? If the latter scenario, what RT dose would you recommend in the setting of a positive post-chemo PET-CT?
2 Answers
Mednet Member
Mednet MemberInvited Expert
Medical Oncology · Rutgers Cancer Institute of New Jersey
Answered on

Interpreting end-of-treatment PET in PMBL can be tricky. False positives here are very common! Fake-outs include thymic rebound masquerading as refractory disease; avidity at rim (which is almost always biopsy-neg); or residual avidity throughout residual mass which again can be biopsy negative. I w...

Join for free or sign in to see the full answer

Mednet Member
Mednet MemberInvited Expert
Radiation Oncology · Duke University Medical Center
Answered on

This is a complex situation without a lot of data to guide us. While I agree mostly with Dr. Matasar, I have some additional comments:

1) Did the pt respond clinically to chemo? If yes, and PET is still positive, that is better then no clinical response

2) Assuming a clinical response and a PET assess...

Join for free or sign in to see the full answer