BACKGROUND: Various studies have shown that papillary thyroid microcarcinoma (PTMC) has a favorable prognosis but has the capacity to be aggressive; thereby, requiring effective treatment.

OBJECTIVES: To determine the clinical characteristics and outcomes of PTMC in Filipino patients diagnosed and treated at Makati Medical Center.

STUDY DESIGN: This is a retrospective, descriptive study.

SUBJECTS AND METHODS: Medical and clinical records of twenty two patients diagnosed and treated for papillary thyroid microcarcinoma from 1993-2004 were reviewed. Statistical means and percentages were used.

RESULTS: The patients' age ranged from 19-73 years old with a mean of 46years. There was a female predominance at 95.45%. One patient (4.5%) had papillary microcarcinoma by fine needle aspiration biopsy (FNAB). Another patient had lymph node and distant metastases (bone) at presentation after near total thyroidectomy without ablation in another medical center and later received 200mCi of radioactive iodine therapy but was lost to follow up. Multifocality was seen in two patients (9%). Five patients (22.7%) had lobectomy while one (4.5%) underwent subtotal thyroidectomy. Near total thyroidectomy was done in five patients (22.7%) while 11 (50%) had total thyroidectomy. Only 12 patients (54.5%) received radiation remnant ablation therapy. One patient who had lobectomy was noted to have nodule recurrence in the remaining lobe while another patient who underwent total thyroidectomy with no radioactive iodine treatment had elevated thyroglobulin (Tg) on follow up. Follow up period ranged from one to 11 years (mean of six years). All patients have survived and were asymptomatic but in some of the patients the cancer activity could not be accurately assessed due to absence of thyroglobulin and thyroid ultrasound determinations.

CONCLUSIONS/RECOMMENDATIONS: Our study compared to foreign studies had a smaller population. Multifocality considered as a predictor of poor prognosis was seen in only two patients. PTMC may have latent/ indolent course and favorable outcomes but may be persistent/ metastatic in some. Combination therapy of near total/ total thyroidectomy with radiation remnant ablation offered greater benefit. Thyroglobulin served as a powerful prognostic factor of persistent/ recurrent disease. Repeat thyroid ultrasound/ biopsy were necessary to document thyroid cancer activity in patients not amenable to thyroglobulin determinations.