Spontaneously Resolved Macrocystic Lymphatic Malformations: Predictive Variables and Outcomes

Abstract

Introduction: Lymphatic malformations are benign, low-flow vascular malformations that typically present at or near birth. Due to morbidity associated with operative treatment, nonoperative treatment with injection of sclerosant has become the mainstay of therapy. Over the past 15 years, several patients at our centre with macrocystic (>2 cm cyst size) lymphatic malformations have seen their lesions resolve spontaneously while awaiting treatment. In this study, we review features of these patients that may contribute to spontaneous resolution. Method: A retrospective chart review was conducted from our Vascular Anomalies Clinic database (1999-2014) of all macrocystic lymphatic malformations; characteristics of patients with spontaneous resolution were reviewed. Results: Of 61 patients with macrocystic lymphatic malformations, 7 cases (11.5%; 4 females, 3 males) resolved spontaneously. Median age at malformation appearance was 2 years (range: 0-6.5 years), with median age at resolution of 4 years (range: 10 months-7 years). Median time from appearance to resolution was 24 months (range: 3-43 months), with a median follow-up time of 4 years (range: 1-15 years). All but 1 case was associated with local or upper respiratory tract infection antecedent to resolution. Six of the 7 lesions were located in the neck. Conclusion: Among the cases reviewed, there was a common theme of upper respiratory tract or local infection antecedent to spontaneous lesion resolution. Compared to the literature, our proportion of malformations presenting after birth and the proportion of malformations presenting in the neck region were higher than those of other series. Although side effects associated with treatment are generally mild and/or rare, risks related to sclerotherapy and the accompanying requirement for general anesthesia in pediatric populations nevertheless exist. As the median time from lesion appearance to resolution was 24 months, it may be reasonable to observe these malformations for up to 24 months before proceeding with treatment if the lesion does not impair function and disfigurement is not considerable, particularly if the lesion presents after birth and/or is located in the neck region.