Pediatric Primary Cutaneous Marginal Zone Lymphoma Treated With Doxycycline
Primary cutaneous marginal zone lymphoma (PCMZL) is a cutaneous B-cell lymphoma that rarely occurs in children. We present a 13-year-old boy with multiple asymptomatic erythematous papules and nodules on the trunk and arms that were confirmed on biopsy to be PCMZL. He was treated with doxycycline and intralesional triamcinolone with improvement of lesions. This case supports the use of doxycycline for the treatment of pediatric PCMZL in patients with widespread involvement despite negative Borrelia serology. Multiple low-risk treatment modalities may be used in conjunction to clear disease in pediatric patients.
Practice Points
- When skin biopsy reveals marginal zone lymphoma, laboratory workup should include a complete blood cell count, chemistry, and serum lactate dehydrogenase levels. If lymphocytosis is present, flow cytometry of peripheral blood cells should be performed.
- For patients with multifocal skin lesions, positive emission tomography with computed tomography is utilized to exclude systemic disease and assess lymph node involvement.
- Treatments for primary cutaneous marginal zone lymphoma include excision, topical steroids, intralesional steroids, intralesional rituximab, radiation therapy, and antibiotics.
- Doxycycline can be considered as a treatment option for pediatric patients with widespread cutaneous involvement.
Doxycycline is utilized in pediatric patients 8 years and older for numerous indications, including treatment of acne, Rocky Mountain spotted fever, and Lyme disease. Use of doxycycline in younger patients typically is avoided given the risk for dental enamel hypoplasia, tooth discoloration, and possible delays in skeletal development. Originally utilized for its antibacterial effects as an intracellular inhibitor of protein synthesis, doxycycline has been repurposed for oncologic therapies. It has been shown to have cytotoxic and antiproliferative properties in various cancer cells and also may inhibit leukemic cell migration.26 In PCMZL, doxycycline initially was utilized in Borrelia-positive patients in Europe and found to improve disease clearance.27 In patients without Borrelia infection, doxycycline is thought to enhance apoptosis through caspase-3 activation along with p53 and Bax upregulation.28
Intralesional triamcinolone alone may not be feasible in pediatric PCMZL patients because of widespread involvement, and doxycycline may be considered as a treatment option. Multiple low-risk treatment modalities may be used in conjunction to clear disease in pediatric patients, as demonstrated in our case.
Acknowledgment—We thank Ali Nael Amzajerdi, MD (Orange, California), for his contributions to the pathologic imaging in this report.
