Association of primary hyperparathyroidism and non-medullary thyroid cancer.

OBJECTIVE

To assess the prevalence of differentiated thyroid cancer among patients with primary hyperparathyroidism (pHPT) and to describe our experience in its treatment.

DESIGN

Retrospective study.

SETTING

Teaching hospital, Germany.

SUBJECTS

322 patients who were operated on for pHPT from 1979-1993 and a control group of 840 patients operated on for nodular goitre during the same time period.

INTERVENTIONS

All patients with non-occult cancer were treated by complete thyroidectomy and adjuvant radioiodine.

MAIN OUTCOME MEASURES

Prevalence of differentiated thyroid cancer, morbidity and mortality.

RESULTS

No patient died. 120 of the 322 patients had simultaneous thyroid resection for either nodular goitre of solitary adenoma; 9 patients had differentiated thyroid cancer (3% of the whole group, or 8% of the group that had thyroid resections). The prevalence among the control group during the same time period war 4%, which is not significantly different. There were 4 occult papillary cancers, 3 papillary stage T2N0 tumours, 1 T2N1 tumour, and 1 follicular tumour. Among the 9 patients with cancer 1 developed transient and 1 permanent paralysis of the laryngeal nerve. Among the 120 patients who had thyroid resections, 45 (38%) developed transient hypocalcaemia and of the 202 operated on for pHPT alone the corresponding figure was 63 (31%). There were 2 postoperative haemorrhages, and 3 wound infections. All patients were alive and free of disease after a mean follow up of 62 months.

CONCLUSION

Though the morbidity of combined thyroid and parathyroid surgery is slightly higher than after operations for pHPT alone we recommend that the indications should not be too rigid because of the benefit that can accrue to patients from the diagnosis of an asymptomatic malignant tumour.