Papillary Thyroid Microcarcinoma: Diagnostic and Histopathological Insights From a Case Report

The coexistence of primary hyperparathyroidism and thyroid nodular disease is frequently encountered in clinical practice, and the simultaneous presence of primary hyperparathyroidism and papillary thyroid microcarcinoma is clinically significant and may pose diagnostic and therapeutic challenges. A 63-year-old postmenopausal woman presented with a short history of painless left-sided neck swelling. Initial ultrasonography revealed a bulky left thyroid lobe with a dominant isoechoic nodule, and fine-needle aspiration cytology (FNAC) categorised the lesion as Bethesda Category IV, suspicious for a Hürthle cell neoplasm. Biochemical evaluation demonstrated markedly elevated intact parathyroid hormone levels, consistent with primary hyperparathyroidism. Subsequent parathyroid scintigraphy localised left-sided parathyroid adenomatous disease. The patient underwent left thyroid lobectomy with excision of the suspected parathyroid tissue. Histopathological examination incidentally revealed a 3 mm papillary thyroid microcarcinoma, with no evidence of lymphovascular invasion or extrathyroidal extension and with clear surgical margins. This case underscores the importance of comprehensive preoperative evaluation in patients with concomitant thyroid and parathyroid abnormalities. Early recognition of synchronous pathology allows for appropriate surgical planning, reduces the need for reoperation, and contributes to favourable clinical outcomes. Reporting such cases enhances awareness of this association and supports an integrated approach to the management of complex endocrine neck disorders.