Case Report: Concomitant BRAF V600E and PIK3CA H1047R mutations in a micro-papillary thyroid carcinoma with extensive nodal metastasis

Abstract

Although most papillary thyroid carcinoma (PTC) cases follow an indolent clinical course, a small subset presents with early extensive lymph node metastasis. Although this aggressive phenotype is frequently linked to the BRAF V600E mutation, concurrent activating mutations in the PI3K/AKT pathway, such as PIK3CA H1047R, are exceedingly rare and their clinical significance remains poorly understood. We report the case of a 42-year-old male with a 7.8-mm solitary papillary thyroid microcarcinoma (PTMC) harboring concurrent BRAF V600E and PIK3CA H1047R mutations. Despite the small size of the primary lesion, extensive cervical lymph node metastases were identified in at least five nodal levels. Although the primary tumor was classified as a low-risk by conventional size-based criteria, the presence of these two oncogenic drivers suggests disproportionately aggressive lymph node dissemination relative to tumor size, underscoring the value of expanded molecular profiling for risk stratification.