Adjuvant radiotherapy after therapeutic lymph node dissection in high-risk Stage III melanoma: the Cambridge experience


Year:

Session type:

Theme:

Lakshmi Harihar1,Amer Durrani2,Sarah Jefferies2,Richard Benson2,Kate Fife2
1Addenbrooke's Hospital,2Addenbrooke's Hospital, Cambridge

Abstract

Background

Adjuvant radiotherapy (RT) to lymph node basins in melanoma is a controversial area. The TROG 02.01 randomised controlled trial of lymph node dissection (LND) plus adjuvant RT versus LND alone demonstrated a benefit in locoregional control but not overall survival. Current national and international guidelines recommend considering adjuvant RT after therapeutic LND in selected patients at high risk of nodal basin recurrence, and in whom the benefit of locoregional recurrence risk reduction is deemed to outweigh the risks of toxicity. However, practice varies widely among centres worldwide.

Cambridge University Hospital (CUH) offers adjuvant RT after LND to ‘high risk’ patients, defined as meeting ≥1 of the TROG 02.01 eligibility criteria. We present an audit of our practice and outcomes.

Method

Retrospective audit of 41 melanoma patients undergoing adjuvant RT after LND at CUH 2010-2015.

Data collected from clinical records.

Kaplan-Meier curves generated for locoregional control (LC), distant recurrence-free survival (DRFS), recurrence-free survival (RFS) and overall survival (OS).

Results

5-year actuarial rates for LC, DRFS, RFS and OS were 80%, 21%, 18% and 26% respectively. Our observed 5-year actuarial LC is comparable to that published for the adjuvant RT arm of the TROG 02.01 study (82%).

Symptomatic late toxicities were documented for 11 patients (27%); however, this is likely to be an underestimation.

Conclusion

While many patients go on to develop distant metastases which limit their survival, there appears to be a small group who derive long-term benefit from the additional locoregional control provided by adjuvant RT and remain recurrence-free.

Furthermore, as uncontrolled nodal basin disease can be extremely symptomatic and adversely affect quality of life, improved locoregional control in itself may become more relevant in future as advances in systemic therapies lead to patients with distant metastases surviving longer. Proactive lymphoedema management and modern radiotherapy techniques can reduce the long-term toxicity somewhat.