Published case study – Primary cutaneous DLBCL too medically fragile for conventional chemotherapy and so administered gentian violet

On 20^th August 2017, in a Bed-to-Bench-Letter to Experimental Dermatology, Shikha Rao from the Emory University School of Medicine Atlanta Veterans Administration Medical Center, Atlanta, GA, USA, et al. presented a case report of a female patient, 84 years of age, with primary cutaneous Diffuse Large B-Cell Lymphoma (DLBCL), leg type.

Key Highlights:

• CD20, BCL2, and BCL6 positive; CD3, CD30, and TP53 negative; contained infiltrating T-cells; little staining for PD-L1; no systemic involvement
• Multiple comorbidities including coronary artery disease, diastolic heart failure, sleep apnea, and diabetes mellitus
• After radiation (30 Gray in 10 sessions) and one IV dose of rituximab, presented with a 3cm nodule on right leg
• Punch biopsy performed and gentian violet (a triphenylmethane dye) introduced to cavity
• Patient was referred for surgical excision but did not take place due to hospitalization for coronary artery disease
• Followed up 4 months later where complete resolution of lesion was observed
• Ongoing remission at 12 months; cannot predict if patient will have lasting response

The authors hypothesized that gentian violet results in signaling changes in DLBCL cells allowing immune clearance to take place. They propose that gentian violet downregulates NADPH oxidase causing subsequent downregulation of NF-kB and Sox2, enhancing antigen presentation of tumor antigens on the cell surface. The authors concluded that gentian violet, as well as similar NADPH-oxidase inhibitors, given systemically warrants further assessment in human Lymphoma in pre-clinical trials.

Abstract:

In this case report, a patient of Primary Cutaneous Diffuse B-cell lymphoma, leg type was treated with intralesional gentian violet as she was judged to be too medically fragile for conventional chemotherapy due to advanced age and multiple serious comorbidities. Gentian violet (Crystal violet/ hexamethyl pararosaniline) is a triphenylmethane dye. It has been shown to have an inhibitory effect on NADPH oxidase, an enzyme family which is found in abundance in reactive oxygen driven tumors such as melanoma and lymphoma. We hypothesize that intralesional gentian violet treatment caused signaling changes in the lymphoma which allowed for immune clearance of the lymphoma. Complete resolution of the patient's lesion was noted on a follow up visit.