Response to Alpelisib in Clinically Distinct Pediatric Patients With PIK3CA -related Disorders

Congenital Vascular Malformations in Children: From Historical Perspective to a Multidisciplinary Approach in the Modern Era-A Comprehensive Review

Congenital vascular malformations (CVMs) are the result of an aberrant development during embryogenesis. Although these lesions are present at birth, they are not always visible yet. Once symptomatic, patients suffer from pain, bleeding, ulcers, infections or lymphatic leakage, depending on the subtype of vessels involved. Treatment includes conservative management, surgery, sclerotherapy, embolization and pharmacological therapy. The clinical presentation varies widely and treatment can be challenging due to the rarity of the disease and potential difficulties of treatment. This review gives an overview of the historical developments in diagnosis and classification and exposes the key elements of innovations in the past decades on the identification of genetic mutations and personalized treatment. These advances in the field and a multidisciplinary approach are highly valuable in the optimization of clinical care aimed at both curing or stabilizing the CVM and pursuing physical and psychosocial wellbeing.

Four-month-old with severe PIK3CA-related overgrowth spectrum disorder successfully treated with alpelisb

PIK3CA-related overgrowth spectrum (PROS) encompasses different clinical entities caused by somatic activating mutations in PIK3CA. Among PROS, CLOVES syndrome represents a severe phenotype with poor survival rate. We present the case of a 4-month-old girl with CLOVES syndrome successfully treated with alpelisib, a PIKC3A inhibitor.

Overgrowth syndromes, diagnosis and management

PURPOSE OF REVIEW

This review will focus on the current knowledge of the diagnosis and management of overgrowth syndromes with specific focus on mosaic conditions and treatment strategies.

RECENT FINDINGS

With the implementation of massively parallel sequencing, the genetic etiology of many classically described overgrowth syndromes have been identified. More recently, the role of mosaic genetic changes has been well described in numerous syndromes. Furthermore, the role of imprinting and methylation, especially of the 11p15 region, has been shown to be instrumental for growth. Perhaps most importantly, many overgrowth syndromes carry an increased risk of neoplasm formation especially in the first 10 years of life and possibly beyond. The systematic approach to the child with overgrowth will aide in timely diagnosis and efficiently align them with appropriate screening strategies. In some cases, precision medical interventions are available to target the perturbed growth signaling pathways.

SUMMARY

The systematic approach to the child with overgrowth aids in the standardization of the diagnostic pathway for these young patients, thereby expediting the diagnostic timeline, enabling rigorous monitoring, and delivering tailored therapeutic interventions.

Facial infiltrating lipomatosis with hemimegalencephaly and lymphatic malformations caused by nonhotspot phosphatidylinositol 3-kinase catalytic subunit alpha mutation

We report an unusual case of facial infiltrating lipomatosis with hemimegalencephaly and lymphatic malformations. In addition to the clinical data and imaging findings, detection of a heterozygous PIK3CA nonhotspot known pathogenic variant C420R in a facial epidermal nevus provided novel insight into the pathogenic effect of somatic PIK3CA mutations.

Primary targeted medical therapy for management of bilateral head and neck lymphatic malformations in infants

OBJECTIVES

Patients born with bilateral head and neck lymphatic malformations (BHNLMs) often require multiple invasive treatments, including tracheostomy. We hypothesized that primary targeted medical therapy (pTMT) with diagnostic needle aspiration reduces the need for invasive therapy such as surgical resection and/or sclerotherapy.

METHODS

Retrospective case review was performed of infants with BHNLMs (Grade 2 or De Serres stage IV and V) treated only at our institution from 2000 to 2021. Patients were divided into two cohorts: those managed with pTMT and those managed with observation, sclerotherapy, or surgical intervention (non-pTMT). Data regarding interventions, clinical outcomes, morbidity, and mortality were analyzed with descriptive statistics.

RESULTS

Nine children with BHNLMs met inclusion criteria. Three (33%) were in the pTMT cohort and six (66%) were non-pTMT. Eight (89%) malformations were genotyped, and all demonstrated hotspot PIK3CA variants. All pTMT patients had sirolimus initiated in the first month of life and underwent needle aspiration of malformation cyst fluid for cell-free DNA samples. All pTMT patients tolerated medical therapy. For the non-pTMT cohort, primary treatment included none (deceased, n = 1, 17%), observation with needle aspiration (n = 1, 17%), surgical resection (n = 2, 33%), or combination surgery and sclerotherapy (n = 2, 33%). Intubation duration, intensive care and initial hospital length of stay were not different between cohorts. Four non-pTMT patients (67%) required tracheostomy, and two (33%) died prior to discharge. All pTMT patients survived and none required tracheostomy. Non-pTMT patients required a median of two invasive therapies prior to discharge (IQR 1-4) and a mean total of 13 over the course of their lifetime (IQR 1-16), compared to the pTMT group who did not require any lifetime invasive therapy, even after initial pTMT and discharge home.

CONCLUSION

This study compares patients with BHNLMs (Grade 2) treated with pTMT versus those treated with observation or invasive therapy. Patients treated with pTMT required no surgical or invasive procedural treatment of their malformations, no tracheostomy placement, no unplanned readmissions after discharge, and had no mortalities. Needle aspiration was useful as a therapeutic adjunct for cell-free DNA diagnosis of PIK3CA variants, which guided TMT.