Congenital Aberrant Muscular Overgrowth of Hands and Feet in Patients With PIK3CA Overgrowth Spectrum: A Multicentric Study of Case Series. Issue 2 (20th April 2021)

• Record Type: Journal Article
• Authors: Delgado-Miguel, Carlos; Miguel-Ferrero, Miriam; Muñoz-Serrano, Antonio J.; Triana, Paloma; Martínez-González, Víctor; Rodríguez-Laguna, Lara; Boente, María del Carmen; Torrelo, Antonio; López-Gutiérrez, Juan C.
• Is Part Of: Journal of Vascular Anomalies. Volume 2:Issue 2(2021)
• Page Start: e010
• Publication Date: 2021-04-20
• Subjects: Aberrant tissue -- Congenital foot deformity -- Congenital hand deformity -- Hyperplasia -- PIK3CA protein; 617.413
• DOI: 10.1097/JOVA.0000000000000010
• Languages: English
• ISSNs: 2690-2702

Abstract

Abstract : Background: The term "congenital muscular hyperplasia of the hand" refers to a distinctive enlargement of the hypothenar eminence associated with ulnar deviation of the metacarpophalangic joints, macrodactyly, and enlargement of the forearm and/or the entire upper extremity. The presence of hyperplastic, aberrant or accessory muscles in the affected areas has been reported. Methods: We present a case series of patients diagnosed with aberrant muscular overgrowth of the hands or feet from 3 international institutions between 2008 and 2018. Results: Fourteen patients are reported. Hand involvement was observed in 10 patients, and in 4 patients, the lateral side of the foot was involved. Nine patients had a vascular malformation (lymphatic and/or capillary) associated either in the affected limb or elsewhere. In all cases, variable degrees of congenital overgrowth of the ipsilateral limb were observed. Skin punch biopsy (5 mm diameter and 3–5 mm depth) was performed on 7 patients. In all of them, striated muscle hyperplasia and the presence of striated muscular fibers in the dermis and hypodermis, thus revealing ectopic muscle, were observed. A somatic pathogenic variant in phosphatidylinositol-3-kinase catalytic α polypeptide ( PIK3CA ) was demonstrated in 5 of the 7 biopsied patients, with a 2.7% to 15.7% of mosaicism (His1047Arg in 2 cases, and Cys378Arg, Glu542Lys, and Cys420Arg, 1 case each). Conclusions: Our case series supports muscular overgrowth as a distinct phenotype within the PIK3CA -related overgrowth spectrum. Although initially described only in the hands, we have reported foot involvement in 4 cases. The role of PIK3CA in muscle overgrowth is not yet well understood.