Copenhagen, Denmark
Onsite/Online

ESTRO 2022

Session Item

Sarcoma/Skin cancer/malignant melanoma
6022
Poster (digital)
Clinical
Innovative radiotherapy technique for the treatment of in-transit or metastatic lower limb melanoma
JOAQUIN VELASCO JIMÉNEZ, Spain
PO-1434

Abstract

Innovative radiotherapy technique for the treatment of in-transit or metastatic lower limb melanoma
Authors:

JOAQUIN VELASCO JIMÉNEZ1, Joaquín Velasco Jiménez2, Marta López Valcárcel3, Patricia Sánchez Rubio4, María Hernández Miguel3, Alfonso Valcárcel Diaz3, Lucía Paisan Palacio3, Sofia Santana Jimenez3, Beatriz Gil Haro3, Olga Engel3, Carlos A. Regueiro Otero5, Jesús Romero Fernández5

1PUERTA DE HIERRO MAJADAHONDA HOSPITAL, RADIATION ONCOLOGY, MAJADAHONDA, Spain; 2CEU San Pablo, Medicina, MADRID, Spain; 3Puerta de Hierro Majadahonda Hospital, Radiation Oncology, Majadahonda, Spain; 4Puerta de Hierro Majadahonda Hospital, Physics, Majadahonda, Spain; 5Puerta de Hierro Majadahonda Hospital , Radiation Oncology, Majadahonda, Spain

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Purpose or Objective

In-transit metastases (ITM) of melanoma are locoregional recurrences confined to superficial lymphatics. Occurrence is 3.4–6.2%. Disproportionately in lower limbs due to gravity and greater lymphatic network. We present a retrospective review of an innovative technique.

Material and Methods

Five consecutive patients treated between April 2011-august 2018 with tomotherapy using hypofractionated regimen of 30 Gy in 6 fractions at 2 fractions/week over 3 weeks.  First patient received 3 x 8 Gy and last patient an integrated boost (SIB) to the macroscopic lesions 5 x 7 Gy with concomitant Nivolumab. The last patient received concomitant Ipilimumab.  PTV30 was defined as all GTV including the primary and superficial lymphatics up to the proximal lesion leaving a corridor with at least a band free from the circumference (first patient PTV had donut shape thus corridor was inside PTV). RECIST was used to assess primary outcomes. Adverse Events assessed using CTCAE V5.0

Results

Patients and responses shown Table 1. Mean follow-up was 31.9 (2.1-40) months. Mean CTV/ PTV volume were 658cc (106-1389) and 1270 cc (241-1693).

PTV mean V30, V28,5 and V27 were 54.7%, 89.5% and 98,3%. Mean corridor volume was 1566cc (243-5008). Corridor mean dose V20, V15 and V10 were 15.6%, 18% and 40%. AEs are shown in Table 2.  Of note is acute edema in the first patient and skin toxicity in the patient who received an integrated boost with nivolumab both resolved.

Conclusion

This innovative technique for ITM in the lower limb resulted in lesion-specific ablation of disease and normal tissue-sparing, with minimal local or systemic adverse effects.