Management of papillary microcarcinoma of the thyroid gland

DESIGN

To investigate the frequency, treatment and clinical behaviour of differentiated microcarcinoma of the thyroid gland (PTMC).

PATIENTS AND METHODS

Out of 376 patients submitted to surgical treatment for differentiated thyroid cancer from June 1980 to October 2003, 77 had been identified has having a PTMC (63 females, 14 males; mean age 43+/-13 years). Sixty-seven patients (87%) met the AMES risk definition for low (group I) and 10 (13%) for high-risk (group II) definition. The surgical procedures were lobo-isthmusectomy (n=14) or subtotal thyroidectomy (n=20) and total thyroidectomy (n=43) with node dissection in 15 cases. Follow-up ranging from 9 to 274 months (mean 124+/-84).

RESULTS

Overall patient survival rates were 100 and 94% at 20 years in groups I and II, respectively (p=ns). There were no significant differences in surgical complications and in survival in patients submitted to total thyroidectomy when compared to partial thyroid resection. The presence of cervical node metastasis did not affect patient survival (p=0.8). The overall mean survival time was 266 months.

CONCLUSIONS

Despite the overall excellent prognosis, PTMC was associated with a 1% disease-related mortality, a 2.5% local recurrence rate, 1% lymph-node recurrence rate, and 1% distant metastasis rate. We recommend total thyroidectomy accompanied by modified neck dissection if enlarged nodes are diagnosed.

Repeated hepatectomy for colorectal metastasis

Between January 1981 and December 1995, 12 patients, who previously underwent hepatic resection for colorectal metastases, were selected for a second liver resection for isolated liver recurrence. Mean interval between first and second resection was 16 months. Eight patients had solitary and 4 multiple metastasis. Two major hepatectomies and 11 wedge resections were performed. Mean follow-up was 37 months. No mortality and 33% morbidity was observed. Three and 5-year actuarial survival rates were 71% and 42%, while disease-free survival was 30%. No patient, primary tumour, or metastases' characteristics were significantly associated to survival. Surgical resection is the only therapy that could offer reasonable chance of long term survival and, in selected case, of cure. A careful patients' selection as well as an accurate surgical technique are essential to reduce post operative mortality and morbidity.

Modified neck dissection in the treatment of differentiated thyroid carcinoma

The prognosis of differentiated carcinoma of the thyroid has been reported to be extremely favourable. Previous studies have concluded that lymph node metastasis do not affect survival rates in patients with differentiated thyroid carcinoma. Therefore, nodal metastasis has not been evaluated as a prognostic factor in recent definitions of risk groups. To determine the significance of nodal disease, we reviewed 219 consecutive patients with differentiated thyroid cancer (191 papillary, 14 follicular and 14 Hurtle cell carcinomas). Fifty-five patients were treated with modified neck dissection and all of them received adjuvant radioiodine. There were recurrences in 25 patients (11.4%), with follow-up ranging from 6 months to 14 years. Systemic disease occurred synchronously in two patients, and four patients died of thyroid carcinoma.

Total thyroidectomy in the treatment of thyroid cancer

Considerable controversy exists about the most appropriate treatment for thyroid cancer. In this report the authors present their experience of 189 patients, all of whom had a total thyroidectomy between June 1980 and December 1993. The age of the patients ranged from 11 to 78 years (mean age: 42 years), there were 144 women and 45 men. Histological types were: 146 papillary, 16 medullary, 10 follicular, eight Hurtle, six insular and three undifferentiated. Coexistent lesions included: 22 thyroiditis, 17 adenomas, one Graves' disease and 22 benign goitre. Fifty-six (29.6%) patients had multifocal papillary cancer (bilateral in 45 cases). Surgical complications included 20 cases of transient recurrent laryngeal nerve palsy, 16 cases of transient and one of permanent hypoparathyroidism, and one respiratory obstruction due to bilateral recurrent laryngeal nerve palsy that required temporary tracheostomy. Two patients were reoperated on due to bleeding. Ninety per cent of patients were discharged within 3 days of thyroidectomy. One hundred and fifty patients were evaluated for 131I treatment by a standardized dosimetry procedure 4 weeks after surgery. Dosimetry was also used to calculate therapeutic 131I doses. Seventy-six patients did not show a 131I uptake above background levels, 56 underwent therapeutic 131I, while in the 18 patients who showed an abnormal uptake of 131I it was decided not to give the therapeutic dose. The authors conclude that total thyroidectomy can be performed with a minimum of permanent disability in patients with malignant thyroid tumours. The theoretical and practical advantages of this kind of surgical strategy make it the treatment of choice for thyroid cancer.

Medullary-thyroid carcinoma - clinical-evaluation of 19 cases

Medullary thyroid carcinoma (MTC) accounts for 5-10% of thyroid malignancies and occurs either as a sporadic or as a familial form. The familial form is inherited in an autosomal dominant pattern, and it is clinically expressed as multiple endocrine neoplasia (MEN), types IIa and IIb or as familial MTC alone. It is possible to make an early diagnosis in patients who have the familial form of the disease as well as to perform an organ specific localisation regarding possible spread of the disease. Calcitonin is a major product of MTC cells and represent the most used tumour marker for diagnosis and evaluation of prognosis. The purpose of this investigation is to analyse our experience with patients treated for MTC in the period 1980-1993.

Avidin-biotin system in radioimmunoguided surgery for colorectal cancer. Advantages and limits

PURPOSE

Radiolabeled monoclonal antibodies (MAbs) have been reported to allow tumor intraoperative detection by means of a gamma-detecting probe. The technology is called the Radioimmunoguided Surgery (RIGS) system. The main inconveniences of the method are 1) the long interval needed for clearance of unattached MAbs from the patient's body, between the injection of the MAb and surgery, and 2) the low sensitivity of current MAbs used in detecting small tumors. We describe a new method to overcome these inconveniences using biotinylated MAbs and avidin in order to obtain a rapid blood clearance of the radiolabeled MAbs both anticarcinoembryonic antigen and antitumor-associated glycoprotein-72 MAbs.

METHODS

Twenty patients with primary and recurrent colorectal cancer have been enrolled in the study; 125I-biotinylated MAbs FO23C5 (anticarcinoembryonic antigen) and B72.3 (antitumor-associated glycoprotein-72) followed by cold avidin were injected in 13 patients and 7 patients, respectively.

RESULTS

A decrease of 94 +/- 3 percent of circulating radioactivity was achieved in 3 to 5 days. Patients underwent surgery approximately seven days after MAb injections rather than after four weeks. Tumors were localized in 14/20 (70 percent) patients (true positive), 2 (10 percent) were false negative, and 4 (20 percent) were true negative. The overall sensitivity level in early-stage primary cancers was 37 percent when related to the presence of disease and 75 percent when related to antigenic expression. The sensitivity for more advanced cancer and for recurrences was 100 percent. Moreover, the in vivo tumor targeting of biotinylated MAb was demonstrated in frozen tumor section by direct streptoavidin-peroxidase staining.

CONCLUSIONS

The avidin-biotin system may enhance applicability and effectiveness of radioimmunoguided surgery (RIGS).