Updates in Diagnosis, Prognosis, and Treatment of Cutaneous T-Cell Lymphoma

Conclusions

• CTCL, especially mycosis fungoides, is often difficult to diagnose because it can mimic benign inflammatory dermatoses, so repeated biopsies, blood studies, and expert dermatopathology review are often needed.
• High-throughput TCR sequencing improves the sensitivity and specificity of clonality testing compared with older PCR-based methods, but clonality alone still is not fully diagnostic because benign clonal T-cell processes exist.
• TRBC1 has become a useful and increasingly standard marker for detecting alpha-beta T-cell clonality in blood, and it can add specificity to flow cytometry and sometimes skin immunohistochemistry.
• Early-stage CTCL generally has a better prognosis and should not be overtreated, while advanced-stage disease is more heterogeneous and remains the major driver of poor outcomes.
• The prospective CLIPI study showed that prognosis in advanced CTCL is better stratified by age, skin large-cell transformation, LDH, and nodal disease than by stage alone.
• Overall survival in advanced CTCL has not clearly improved despite newer therapies, suggesting that better treatments are still needed.
• Home narrowband UVB phototherapy is an important and effective option for early-stage CTCL and can be pursued more successfully with proper documentation and prior treatment history.
• Immune checkpoint inhibitors show real activity in CTCL, particularly in MF and Sézary syndrome, and hyperprogression does not appear to be a dominant safety problem in these subtypes.
• Patients starting checkpoint inhibitors should be counseled about possible initial flares that may mimic progression, and these flares can often be managed with topical steroids and sometimes radiation.
• The presentation’s overall message is that diagnosis, prognosis, and treatment in CTCL are all improving, but clinicians still need careful clinicopathologic correlation and individualized management.