When Lymphoma Comes Back: Recurrence Questions

A scan that lights up is a reason to look, not a diagnosis. Lymph nodes swell for many reasons, and inflammation after treatment can show up on imaging exactly like disease.

The first question is therefore simple. Will a biopsy be done, and of which site? A tissue diagnosis at relapse does two things. It confirms lymphoma is actually back. And it re-reads the disease, which can have changed since the first diagnosis.

That second point matters most in slow-growing lymphoma. Follicular lymphoma can transform into a faster, more aggressive type, and transformation changes the whole treatment plan. A biopsy is how that is found.

Most lymphoma imaging now uses PET-CT, which combines a scan of structure with a scan of metabolic activity. Results are read on the Deauville scale, and NCI treats a Deauville score of 4 or 5 as a positive result.

Ask for the Deauville score itself, not just the word on the report. Ask also whether the scan is being compared to a specific earlier scan, and which one.

One technical note is worth having. NCI notes PET-MRI scans may give equivalent staging information at 25 percent of the radiation dose of PET-CT. If you are young, or have had many scans, that is a fair question to raise.

Many people assume that routine scans are what catch a return. In some lymphomas the evidence says otherwise.

NCI notes that several retrospective reviews suggest routine surveillance scans offer little to no value in diffuse large B-cell lymphoma when a complete remission was reached after induction treatment.

In practice, most recurrences announce themselves through symptoms, and the ones to report are specific. NCI defines B symptoms as unexplained weight loss of more than 10 percent of body weight over 6 months, unexplained fever with a temperature above 38 °C (100.4 °F), and drenching, recurrent night sweats. NCI adds that fevers and weight loss are the most significant of these. Night sweats alone do not carry the same weight.

Report a new lump that persists more than two weeks, any of the B symptoms, or a lump that hurts. Ask the team what their own threshold is for arranging imaging.

Hodgkin lymphoma is uncommon and often curable. The American Cancer Society projection for 2026, published on SEER Stat Facts, is 8,920 new cases and 1,100 deaths in the United States, while NCI's PDQ summary still repeats the 2025 pair, and that summary states that up to 90 percent of newly diagnosed patients can be cured.

Recurrence is not the end of that story. NCI states that more than half of patients with recurrent Hodgkin lymphoma can achieve long-term disease-free survival, or cure, using reinduction treatment followed by a stem cell transplant.

NCI describes the pattern as a 75 percent rule. About 75 percent of patients reach a clinical complete remission with salvage reinduction. Of those who then have an autologous stem cell transplant, about 75 percent are free of disease at 4 years.

Autologous means the stem cells come from you, collected before high-dose treatment and given back afterward.

Not all relapses carry the same outlook. NCI lists the poor prognostic factors:

• Primary refractory disease, meaning the lymphoma never went into remission. This carries the worst outlook.
• Relapse less than 12 months after the initial treatment.
• Failure to reach complete remission after reinduction, shown by a positive PET-CT with a Deauville score of 4 or 5 followed by growth in the size or number of disease sites.
• B symptoms at the time of relapse.
• Disease outside the lymph nodes at relapse.
• More than two previous salvage regimens.

The timing item is the one to check first. NCI notes that among patients who started with early-stage favorable disease and later relapsed, more than 75 percent relapsed more than 12 months after diagnosis. Ask where your interval falls.

NCI names six categories for recurrent classic Hodgkin lymphoma:

• Pembrolizumab or nivolumab, alone or with chemotherapy.
• Brentuximab vedotin.
• Brentuximab vedotin plus nivolumab.
• Chemotherapy followed by stem cell transplant.
• Combination chemotherapy.
• Radiation therapy.

Pembrolizumab and nivolumab are checkpoint inhibitors. They block a brake on immune cells called PD-1. In a phase II trial, 37 patients with relapsed or refractory disease received three cycles of pembrolizumab with two cycles of ICE chemotherapy, which is ifosfamide, carboplatin and etoposide, before an autologous transplant. The complete response rate was 86.5 percent and the overall response rate was 97.3 percent. Stem cell collection was not impaired, which matters when a transplant is planned next.

A second phase II trial gave pembrolizumab with GVD chemotherapy, which is gemcitabine, vinorelbine and liposomal doxorubicin, to 39 transplant-eligible patients.

Ask which of these six the team is proposing, and what the plan is if the first does not work. Sequence is a real decision here, not an afterthought.

Indolent B-cell non-Hodgkin lymphoma behaves differently. Relapse is expected over a long life with the disease, and the goal is often control rather than cure.

NCI lists the options for recurrent indolent B-cell lymphoma: rituximab alone or with chemotherapy; obinutuzumab alone or with chemotherapy; lenalidomide with rituximab; zanubrutinib with obinutuzumab; an EZH2 inhibitor; bispecific T-cell engagers; CAR T-cell therapy; stem cell transplant; and palliative radiation therapy.

Several of these depend on the lymphoma cells carrying a specific marker or gene change. Ask what testing was done on the relapse biopsy and what it showed. Our page on biomarker testing explains what those reports contain.

Salvage treatment and transplant carry consequences worth knowing about before consenting rather than after.

NCI reports that after regimens containing MOPP, the risk of acute myeloid leukemia is approximately 3 percent at 10 years, with the peak occurring 5 to 9 years after therapy. The risk after ABVD appears lower. Late effects of autologous stem cell transplant include second cancers, hypothyroidism, low sex hormone levels, shingles, depression and heart disease.

Ask for these to be listed in a written survivorship plan, with the monitoring schedule attached, before treatment starts.

• Is a biopsy planned, and will it be tested for transformation to a more aggressive type?
• What is the Deauville score, and which prior scan is it being compared against?
• How long was my remission, in months?
• Which of NCI's poor prognostic factors apply to me?
• Is the goal cure, long-term control, or symptom relief?
• Am I a transplant candidate, and does the treatment being proposed first affect whether stem cells can be collected later?
• Which trials are open, and does eligibility depend on how many salvage regimens I have already had?

That last question is not theoretical. More than two prior salvage regimens is itself on NCI's adverse list, and many trials cap prior lines. Our page on clinical trial versus standard treatment covers how to weigh the two. For the disease overall, see lymphoma.

Salvage treatment drops your infection-fighting cells further than first-line treatment usually does.

• Call 911 or go to an emergency department if a fever comes with confusion, clammy or sweaty skin, a fast or weak pulse, breathlessness, or extreme pain. CDC lists those as signs of sepsis, which it calls a life-threatening emergency.
• Call 911 or go to an emergency department if you have a swollen face or neck, or your breathing or swallowing is being blocked by a growing lump.
• Get the oncology line on the phone straight away, at any hour, if you have a temperature of 100.4°F (38°C) or higher, or shaking chills, at any point after chemotherapy. Do not settle for a same-day slot. CDC treats a fever during chemotherapy as a medical emergency, and salvage regimens leave you with even less protection. If no one picks up within minutes, go to an emergency department and tell staff you are on lymphoma treatment.
• Get emergency care if you have had CAR T-cell therapy and develop a high fever, or become confused, unusually sleepy, or hard to understand when you speak. NCI describes those as cytokine release syndrome and neurologic toxicity, and both are treatable when caught early.
• Call your care team the same day if you have a painful band of blistering rash. Shingles is a known late effect after transplant.
• Call your care team within a day or two if drenching night sweats, unexplained fever, weight loss, or a growing lump return between visits. These are how most recurrences are found, not on scans.

• NCI PDQ on Hodgkin lymphoma, for doctors
• NCI PDQ on indolent B-cell non-Hodgkin lymphoma, for doctors
• NCI PDQ on Hodgkin lymphoma, for patients
• CDC on sepsis
• NCI on CAR T-cell therapy
• SEER Stat Facts: Hodgkin lymphoma