For Emergencies:
What are glucocorticoids?
- Glucocorticoids are steroid hormones naturally produced by the adrenal cortex but can also be given as medications e.g. Prednisolone and dexamethasone.
How do they affect lymphoma?
- Glucocorticoids help destroy lymphoma cells in dogs and cats primarily through inducing apoptosis— a form of programmed cell death — especially in lymphoid cells, including B and T lymphocytes.
There are several mechanisms by which they destroy lymphoma cells:
Binding to Glucocorticoid Receptors
- Glucocorticoids enter lymphoma cells and bind to cytoplasmic glucocorticoid receptors (GRs).
- This complex moves into the nucleus and affects gene transcription.
Altered Gene Expression
- They upregulate pro-apoptotic genes (e.g. Bim – Bcl-2-interacting mediator of cell death, encoded by BCL2L11). This gene promotes cell death.
- They downregulate anti-apoptotic genes (e.g. Bcl-2). This is often over-expressed in high grade lymphomas and is also a mechanism for resistance to therapy.
- They suppress pro-inflammatory cytokines that may support tumour survival.
The end result is apoptosis of lymphoid tumour cells, especially those from highly glucocorticoid-sensitive B-cell lymphomas.
Do T- and B-Cell lymphomas respond the same to glucocorticoids?
Although both types of lymphocyte will often respond to steroids, there are some potential differences between these subtypes.
B-cell lymphomas tends to have more robust apoptosis in response to glucocorticoids due to:
- Higher expression of glucocorticoid receptors.
- Lower expression of resistance proteins like Bcl-2 in some cases.
- T-cell lymphoma is often more resistant, especially subtypes like epitheliotropic lymphoma or hepatosplenic T-cell lymphoma, which have inherently more aggressive biology.
Can lymphoma treated with glucocorticoids be effective?
- Treatment of lymphoma with glucocorticoids is considered as a palliative therapy resulting in shorter-term treatment of the disease in select cases where more effective treatments are not possible for various reasons. Around 80% of patients treated with steroids can see a good response with an improved appetite and reduction in node size, however the response is typically shorter with a median survival time of 1-3 months.
So do steroids influence the treatment or investigation into lymphoma?
If you remember anything from this discussion, it should be: Think Twice Before Giving Steroids in cases of lymphoma or those which you suspect of lymphoma without considering the options!
Even a few days of corticosteroids – at any dose – before diagnosing lymphoma can significantly worsen outcomes in dogs, particularly with diffuse large B-cell lymphoma.
Upfront steroid use can:
- Reduce response to chemotherapy
- Shorten survival times
- Result in lower diagnostic yield via flow cytometry
In a newly published retrospective study of 273 dogs with multicentric DLBCL (Marconato et al 2025), 67 (24.5%) had received steroids before treatment. Alarmingly, in 94% of these cases, steroids were given specifically to manage lymphoma.
These dogs had significantly poorer outcomes than those who did not receive steroids, regardless of dose or duration. Moreover, the diagnostic yield of flow cytometry was significantly lower in pre-treated dogs making diagnosis and immunophenotyping more difficult.
The studies take-home messages were:
- Steroids are powerful drugs – not harmless stop gaps in therapy.
- Before you reach for them, make sure a proper diagnosis is in place and the clinical benefit outweighs the risks.
- What seems like relief today could cost your patient tomorrow.
If you would like to discuss any of this or discuss a particular case, do not hesitate to contact us here any time.
Reference:
Dose and Duration of Up front Steroid Administration Have no Prognostic Impact in Dogs With Multicentric Diffuse Large B-Cell Lymphoma
Ilaria Maga, Silvia Sabattini, Valeria Martini, Fulvio Riondato, Luca Aresu, Laura Marconato July, 2025. Journal of Veterinary and Comparative Oncology.
