DR. HORWITZ: Thank you, we'll go further into the selection of initial therapies but first circle back, I was curious as to how often your center comes to a different diagnosis than the referring center, and are there pitfalls you see that alert you to be suspicious of diagnosis.
DR. SHUSTOV: I'd say probably 10% of cases that we see at our center will be reclassified by our hematopathologists. In most cases, they do not necessarily reverse the diagnosis, but provide further clarification. It is occurring to me that in the community, pathologists are less likely to call the subtype of T-cell lymphoma and limit the report to the general description of T-cell lymphoprolipherative disorder, or state something like “consistent with T-cell lymphoma with features of AITL, or with features of anaplastic lymphoma.” I would admit though, that sometimes it's very difficult to identify the specific subtype of PTCL even in the expert hands; but I'd say these cases would constitute no more than 5% of PTCL patients.
DR. HORWITZ: And in your experience is it mostly fine tuning a T-cell lymphoma diagnosis, or do you see totally different diagnoses?
DR. MOSKOWITZ: Usually review by expert hematopathologists simply leads to fine-tuning the T-cell lymphoma diagnosis, however, I occasionally see significant changes in diagnosis. Often, alterations or clarification of a diagnosis are made possible only after we provide the pathologist with clinical history. For example, a lymph node biopsy may be interpreted as ALCL, however the knowledge that the particular patient has a history of mycosis fungoides would lead the pathologist to consider the diagnosis of large cell transformation of mycosis fungoides rather than ALCL. In such a case, molecular studies are helpful in confirming that the lymph node findings originate from the same clone as that in the original mycosis fungoides lesions, rather than representing a second primary.
DR. FANALE: Very occasionally, I've seen patients truly “with a misdiagnosis and a complete revision of diagnosis” and, usually, those pitfalls that I've seen them occasionally have been the young patients—the young patients who generally have disease in the thorax and neck, who are treated as though they have classical Hodgkin lymphoma, who have very significant progression of disease on standard of care treatment. So it's important that not all cases that have CD30 positivity are classical Hodgkin lymphoma even if the patient is young.
DR. HORWITZ: I often think the systemic T-cell lymphomas usually behave in an aggressive fashion so when the clinical picture and the diagnosis don't really fit, I think about getting a second biopsy before we finalize the diagnosis. Of course, when people are ill with obviously progressing disease, you may need to move more quickly.
I often think the systemic T-cell lymphomas usually behave in an aggressive fashion so when the clinical picture and the diagnosis don't really fit, I think about getting a second biopsy before we finalize the diagnosis. To move on, when you first see a patient, what is the decision tree in your mind in terms of picking therapy or planning therapy, or what kind of things do you consider?
DR. MOSKOWITZ: The first thing I think about when deciding upon treatment for a patient with T-cell lymphoma is whether or not I plan to use a curative approach to therapy. As was mentioned by Michelle, this decision is partly based upon the patients’ comorbidities and age. For patients who are eligible for curative therapy, our frontline approach for the most common types of T-cell lymphoma is to use CHOP with or without etoposide followed by consideration for autologous stem cell transplant in first remission. There are certainly individuals for whom such an aggressive strategy would not be appropriate due to age or co-morbidities. In these individuals, we may consider CHOP-based therapy alone or sometimes even milder approaches aimed at disease control.
DR. HORWITZ: Andrei, are you similar in the CHOP/CHOEP paradigm? And if so, what do you think of those data? How do you decide between the two and when do you do that regimen versus something different?
DR. SHUSTOV: I think I will double or triple what Michelle and Alison just said; for me, the two most important decisions that I have to make in the first encounter with patients with newly diagnosed PTCL are: 1) whether we're going to pursue curative approach strategy; and 2) whether the patient can tolerate the intensity of treatments that would provide him/her with the best chance of cure or long term remission. Patients who are elderly and have high risk disease would be very hard to cure, especially considering that the consolidative transplant might carry high rates of morbidity or mortality; more conservative strategies might be appropriate in these cases. On the other hand, younger and more fit patients might benefit more from intensified initial regimens—ie, CHOEP—followed by high-dose therapy and either autologous or allogeneic stem cell transplant (ALLO).
I usually have a long initial discussion with patients and families during which we decide on the intent of treatment and what to expect from certain regimens in terms of toxicities. I typically choose CHOEP regimen (or infusional version, etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin [EPOCH]) for younger patients based on recent German data, even though this was a retrospective study and benefit of adding etoposide only approached statistical significance for the majority of PTCL subtypes.2 In older patients, I try to avoid anthracyclines, especially in the palliative intent setting, based on the retrospective analysis by the International T-Cell Lymphoma Project, and frequently use CEOP regimen (CHOEP minus anthracycline).3 I find that the majority of older patients tolerate this treatment somewhat better than anthracycline-containing combinations like CHOP.
In the very elderly and frail patients, I try to avoid combination chemotherapy all together. It is a somewhat easier decision for patients with AITL. Some of them are more indolent than other sub-types, and I would treat such patients with immunomodulatory approach, ie with a combination of prednisone and cyclosporine; then, I would consider single agent therapy with one of the recently approved agents for relapsed and refractory PTCL. I would also double what Michelle said in regard to making the best attempt to enroll patients into open clinical trials, because the current standards are not really satisfactory for many T-cell lymphoma patients.
DR. HORWITZ: It sounds like we all approach a new patient similarly. However, several of our up front trials are randomized against CHOP as opposed to CHOEP. When you're consenting a patient to those trials, how do you explain it to a patient or how important do you think the etoposide is?