title: Incidental carcinoma in multinodular goiter: risk factors.
abstract: The aim of the study was to analyze the frequency of incidental thyroid carcinoma (unknown tumor smaller than or equal to 10 mm) in a consecutive series of 462 total thyroidectomies for multinodular goiter and to investigate the clinical risk factors for this type of malignancy. A retrospective,  single-center study of outcome data collected from patients with preoperative diagnosis of multinodular goiter who underwent total thyroidectomy at the General Surgery Unit of Pavia (Italy) between January 2000 and December 2008 was performed. Possible risk factors for malignancy were: gender,  age, time of evolution of goiter, presence of a dominant nodule in multinodular goiter, hyperthyroidism, history of radiation to the neck, residence in an area of endemic goiter, prior thyroid surgery, calcifications in the goiter detected by neck ultrasound or chest X-rays, and a family history  of thyroid diseases. In a 9-year period, 462 patients underwent total thyroidectomy. We found 41 cases of incidental thyroid carcinoma; the most common histopathological type was papillary. The multivariable analysis demonstrated that the clinical variables associated with occult carcinoma  were a personal history of radiation therapy to the neck, the presence of calcifications detected by ultrasound or neck X-rays, and a family history of thyroid diseases; residence in an area of endemic goiter was a protective factor. A personal history of radiation to the neck, detection of  calcifications by ultrasound or by neck X-rays, and a family history of thyroid diseases should be considered clinical risk factors for malignancy in multinodular goiter.
authors.affiliation: Department of General Surgery, Fondazione I.R.C.C.S. Policlinico S. Matteo of Pavia, University of Pavia, Italy. ivanbot@yahoo.it
authors.forename: Ivan
authors.initials: I
authors.lastname: Botrugno
authors.forename: Federico
authors.initials: F
authors.lastname: Lovisetto
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Cobianchi
authors.forename: Sandro
authors.initials: S
authors.lastname: Zonta
authors.forename: Catherine
authors.initials: C
authors.lastname: Klersy
authors.forename: Alberto
authors.initials: A
authors.lastname: Vailati
authors.forename: Paolo
authors.initials: P
authors.lastname: Dionigi
authors.forename: Vassili
authors.initials: V
authors.lastname: Jemos
mesh_terms: D044963:Biopsy, Fine-Needle; D002291:Carcinoma, Papillary / Q000175:diagnosis / Q000453:epidemiology* / Q000601:surgery; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006044:Goiter, Nodular / Q000175:diagnosis / Q000453:epidemiology* / Q000601:surgery; D006801:Humans; D015994:Incidence; D033162:Incidental Findings; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D013961:Thyroid Gland / Q000000981:diagnostic imaging / Q000473:pathology; D013964:Thyroid Neoplasms / Q000175:diagnosis / Q000453:epidemiology* / Q000601:surgery; D013965:Thyroidectomy; D013997:Time Factors; D014463:Ultrasonography