Disparities between male and female patients with thyroid cancers: sex difference or gender divide?

OBJECTIVE: This investigation was undertaken to quantify histopathological disparities between male and female patients with sporadic and hereditary thyroid cancers, which may reflect a biological 'sex difference' or a behavioural 'gender divide'.
DESIGN: Retrospective cohort analysis (November 1994-January 2006). PATIENTS: 1298 Consecutive surgical patients with sporadic papillary (n = 587), sporadic follicular (n = 232), sporadic medullary (n = 320), and hereditary medullary thyroid cancers (n = 159) from a tertiary referral centre. MEASUREMENTS: Age at diagnosis of cancer, primary tumour diameter, frequency of extrathyroidal extension, lymph node and distant metastases, and cancer subtypes.
RESULTS: Primary diameters of sporadic tumour entities (papillary, 26.0 vs. 19.3 mm; follicular, 54.9 vs. 35.1 mm; and medullary, 27.9 vs. 20.8 mm), but not hereditary medullary cancers, were significantly (P <or= 0.001) larger in male patients. Likewise, lymph node metastases from sporadic papillary cancers (60%vs. 44%, P < 0.001), the insular subtype in sporadic follicular cancers (22%vs. 8%, P = 0.003), extrathyroidal extension of sporadic medullary cancers (35%vs. 15%, P < 0.001), and distant metastases from sporadic medullary cancers at the most recent operation (29%vs. 15%, P = 0.002) were seen significantly more often with male patients. No significant differences were observed between male and female patients with hereditary medullary cancers, half of which were detected by screening.
CONCLUSIONS: Our data emphasize the need for earlier diagnosis and intervention in male patients to ensure that male sex will cease sometime to constitute an ominous prognostic marker of advanced thyroid cancer.