What should I do if I have non-Hodgkin's lymphoma and develop a skin rash?

Management of Skin Rash in Non-Hodgkin's Lymphoma

For patients with non-Hodgkin's lymphoma who develop a skin rash, prompt evaluation and treatment is necessary as it may represent lymphoma-related manifestations or treatment complications that can significantly impact morbidity and mortality.

Initial Assessment

When a skin rash develops in a patient with non-Hodgkin's lymphoma (NHL), several important considerations must be addressed:

Determine if the rash is lymphoma-related or not:

1. Lymphoma-specific skin manifestations:

   • Primary cutaneous involvement by NHL
   • Secondary cutaneous spread from systemic NHL

2. Non-lymphoma causes:

   • Drug reactions (chemotherapy, rituximab)
   • Infections (fungal, viral) due to immunosuppression
   • Paraneoplastic manifestations
   • Unrelated dermatological conditions

Diagnostic Approach

1. Skin examination and biopsy:

   • Location, distribution, and morphology of lesions
   • Excisional or incisional biopsy of representative lesion 1
   • Histopathology with immunohistochemistry to determine if lymphoma-related 1

2. Laboratory workup:

   • Complete blood count with differential
   • Comprehensive metabolic panel including liver function tests
   • LDH (elevated in active lymphoma) 1, 2

Management Algorithm

If rash is confirmed as cutaneous lymphoma:

1. For primary cutaneous B-cell lymphoma:

   • Localized lesions: Surgical excision or local radiotherapy 2
   • Multiple/widespread lesions: Rituximab (systemic or intralesional) 2, 3
   • Aggressive subtypes (like primary cutaneous diffuse large B-cell lymphoma, leg type): R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) 2

2. For secondary cutaneous involvement from systemic NHL:

   • Treat underlying systemic disease with appropriate chemotherapy regimen
   • For non-Hodgkin lymphoma: Treatment with cimetidine, carbamazepine, gabapentin, or mirtazapine may help relieve associated pruritus 1
   • For temporary relief: Consider narrowband UVB phototherapy 1

If rash is not lymphoma-related:

1. Drug-induced rash:

   • Evaluate timing of rash in relation to medications
   • Consider drug cessation if risk-benefit analysis is favorable 1
   • For rituximab-related reactions: slow infusion rate, premedicate with antihistamines and corticosteroids 3

2. Infection-related rash:

   • Evaluate for fungal infections (common in NHL patients) 4
   • Treat with appropriate antifungal, antiviral, or antibacterial therapy

3. Paraneoplastic pruritus with rash:

   • May be relieved with paroxetine, mirtazapine, granisetron, or aprepitant 1
   • Topical treatments for symptomatic relief

Special Considerations

1. Monitoring and follow-up:

   • Regular skin examinations every 3 months for the first 1-2 years 2
   • Repeat imaging if cutaneous lymphoma was diagnosed

2. Prevention strategies:

   • Sun protection (skin cancers are more common in NHL patients) 5
   • Proactive skin care to prevent xerosis and secondary infections

3. Warning signs requiring urgent evaluation:

   • Rapidly progressing lesions
   • Ulceration or necrosis
   • Systemic symptoms (fever, night sweats, weight loss)

Pitfalls to Avoid

1. Don't assume all rashes in NHL patients are benign - cutaneous involvement can indicate disease progression or transformation

2. Don't miss hepatitis B screening before rituximab treatment, as reactivation can be fatal 3

3. Don't overlook the possibility of drug-induced rashes - NHL patients often receive multiple medications

4. Don't delay biopsy of suspicious lesions, as early diagnosis impacts treatment outcomes

5. Don't underestimate the impact of skin manifestations on quality of life - pruritus and visible lesions can cause significant distress

By following this structured approach, patients with non-Hodgkin's lymphoma who develop skin rashes can receive appropriate evaluation and treatment, potentially improving both disease outcomes and quality of life.