Maria Rosa Pelizzo

Complications of Thyroid Surgery: Analysis of a Multicentric Study on 14,934 Patients Operated on in Italy over 5 Years

Complication rates associated with thyroid surgery can be evaluated only through analysis of case studies and follow-up data. This study covers postoperative data from 14,934 patients subjected to a follow-up of 5 years. Among them, 3130 (20.9%) underwent total lobectomy (TL), 9599 (64.3%) total thyroidectomy (TT), 1448 (9.7%) subtotal thyroidectomy with a monolateral remnant (MRST), and 757 (5.1%) subtotal thyroidectomy with bilateral remnants (BRST). A total of 6% of the patients had already been operated on. Persistent hypoparathyroidism occurred after 1.7% of all the operations, and temporary hypoparathyroidism was noted in 8.3%. Permanent palsy of the laryngeal recurrent nerve (LRN) occurred in 1.0% of patients, transient palsy in 2.0%, and diplegia in 0.4%. The superior laryngeal nerve was damaged in 3.7%; dysphagia occurred in 1.4% of cases, hemorrhage in 1.2%, and wound infection in 0.3%. No deaths were reported. A significant rate of LRN damage was noted, which has an important impact on the patient’s social life. Hypoparathyroidism after total thyroidectomy is an important complication that can be successfully treated by therapy, although it is not always easily managed in special circumstances such as in young persons or pregnant women. The complications associated with thyroid surgery must be kept in mind so the surgeon can carefully evaluate the surgical and medical therapeutic options, have more precise surgical indications, and be able to give the patient adequate information.

Surgical Versus Conservative Management for Subclinical Cushing Syndrome in Adrenal Incidentalomas: A Prospective Randomized Study

Objective:To compare the clinical outcome of patients with subclinical Cushing syndrome (SCS) due to an adrenal incidentaloma (the autonomous hypersecretion of a small amount of cortisol, which is not enough to cause clinically-evident disease) who underwent surgery or were managed conservatively. Summary Background Data:The most appropriate management of SCS patients is controversial, either adrenalectomy or close follow-up being recommended for their treatment. Methods:Over a 15-year period, 45 SCS patients were randomly selected to undergo surgery (n = 23) or conservative management (n = 22). All surgical procedures were laparoscopic adrenalectomies performed by the same surgeon. All patients were followed up (mean, 7.7 years; range, 2–17 years) clinically by 2 experienced endocrinologists 6 and 12 months after surgery and then yearly, or yearly after joining the trial, particularly monitoring diabetes mellitus (DM), arterial hypertension, hyperlipidemia, obesity, and osteoporosis. The study end point was the clinical outcome of SCS patients who underwent adrenalectomy versus those managed conservatively. Results:All 23 patients in the surgical arm had elective surgery. Another 3 patients randomly assigned to conservative management crossed over to the surgical group due to an increasing adrenal mass >3.5 cm. In the surgical group, DM normalized or improved in 62.5% of patients (5 of 8), hypertension in 67% (12 of 18), hyperlipidemia in 37.5% (3 of 8), and obesity in 50% (3 of 6). No changes in bone parameters were seen after surgery in SCS patients with osteoporosis. On the other hand, some worsening of DM, hypertension, and hyperlipidemia was noted in conservatively-managed patients. Conclusions:Based on the results of this study, laparoscopic adrenalectomy performed by skilled surgeons appears more beneficial than conservative management for SCS patients complying with our selection criteria. This trial is registered with Australian Clinical Trials Registry number, ANZCTR12608000567325.

The Variant rs1867277 in FOXE1 Gene Confers Thyroid Cancer Susceptibility through the Recruitment of USF1/USF2 Transcription Factors

In order to identify genetic factors related to thyroid cancer susceptibility, we adopted a candidate gene approach. We studied tag- and putative functional SNPs in genes involved in thyroid cell differentiation and proliferation, and in genes found to be differentially expressed in thyroid carcinoma. A total of 768 SNPs in 97 genes were genotyped in a Spanish series of 615 cases and 525 controls, the former comprising the largest collection of patients with this pathology from a single population studied to date. SNPs in an LD block spanning the entire FOXE1 gene showed the strongest evidence of association with papillary thyroid carcinoma susceptibility. This association was validated in a second stage of the study that included an independent Italian series of 482 patients and 532 controls. The strongest association results were observed for rs1867277 (OR[per-allele] = 1.49; 95%CI = 1.30–1.70; P = 5.9×10−9). Functional assays of rs1867277 (NM_004473.3:c.−283G>A) within the FOXE1 5′ UTR suggested that this variant affects FOXE1 transcription. DNA-binding assays demonstrated that, exclusively, the sequence containing the A allele recruited the USF1/USF2 transcription factors, while both alleles formed a complex in which DREAM/CREB/αCREM participated. Transfection studies showed an allele-dependent transcriptional regulation of FOXE1. We propose a FOXE1 regulation model dependent on the rs1867277 genotype, indicating that this SNP is a causal variant in thyroid cancer susceptibility. Our results constitute the first functional explanation for an association identified by a GWAS and thereby elucidate a mechanism of thyroid cancer susceptibility. They also attest to the efficacy of candidate gene approaches in the GWAS era.

Identification of the Nonrecurrent Laryngeal Nerve during Thyroid Surgery: 20-Year Experience

The nonrecurrent laryngeal nerve, which is rarely observed during thyroidectomy, is at high risk for damage. During a 20-year period 6000 thyroidectomies were performed at our institution, and during these operations inferior laryngeal nerves were routinely identified in all the patients with a standard procedure based on the usual anatomic landmarks. A nonrecurrent laryngeal nerve was observed on the right side in 31 cases (0.51%), with no anatomic anomalies found on the left side. The nerve anomaly was diagnosed preoperatively in five patients. A vocal cord deficit, caused by a nerve lesion, was observed in four cases (12.9%). Our results suggest that the best way to avoid morbidity is routine identification of the nerve. This can be done by carefully identifying all the thyroid structures and being suspicious of the presence of the abnormality when the inferior laryngeal nerve is not found in a classic position.

Zuckerkandl’s tuberculum: an arrow pointing to the recurrent laryngeal nerve (constant anatomical landmark)

A better knowledge of thyroid gland anatomy and embryology has made surgical management of thyroid disorders safer, particularly by decreasing the occurrence of injury to the recurrent laryngeal nerves. Although the best method for protecting these nerves during thyroidectomy is controversial, the most experienced surgeons agree about the need for their routine exposure. Recently, we have been considering Zuckerkandl’s tuberculum as an anatomic landmark for tracing the nerve during thyroidectomy, because of the constant relationship (demonstrated in specific contributions of embryology) between the tuberculum and the termination of the recurrent nerve before it enters the larynx. Our technique of thyroidectomy approaches the recurrent laryngeal nerve from Zuckerkandl’s tubercle if present; we report our criteria for determining whether Zuckerkandl’s tuberculum was there or not, and its relative size in a series of 104 consecutive thyroid lobectomies.

Molecular characteristics in papillary thyroid cancers (PTCs) with no 131I uptake

Objective  Papillary thyroid cancers (PTCs) with no iodine uptake have an aggressive behaviour and a poor prognosis. The aim of our study was to characterize, at molecular level, a subset of PTC with no 131 iodine (131I) uptake.

High prevalence of occult papillary thyroid carcinoma in a surgical series for benign thyroid disease.

In a surgical series of 277 consecutive patients operated on the thyroid for benign diseases, a high prevalence rate (10.5%) of occult papillary carcinoma was found by means of an accurate histologic examination. Indications for surgery were euthyroid multinodular goiter in 25 patients, autonomously hyperfunctioning adenoma in 2 and Graves’ disease in 2 patients. Neoplastic foci were unilaterally found in 25 cases but multifocally in 6 and bilaterally in 4 cases: the diameters ranged from 2-10 mm. After operation (14 subtotal and 15 total thyroidectomies), all patients received TSH-suppressive doses of T4. At a mean follow-up of 5.6 years, neither local recurrences nor lymph node or distant metastases had occurred; no patient died of the tumor. In keeping with other surgical and autopsy series, the prevalence of occult thyroid carcinoma in a normal population is calculated to be about 5-10%, whereas it is known that the prevalence of clinically evident thyroid cancer is only 0.05%. This means that only 1-2% of occult carcinomas may evolve in an overt tumor during life. In view of such an epidemiologic difference and the favorable course of our patients, although the mean follow-up is rather short, we suggest that lobectomy plus T4 treatment may be considered an adequate therapeutic approach in patients with occult papillary thyroid carcinoma.

MicroRNA Profiles in Familial and Sporadic Medullary Thyroid Carcinoma: Preliminary Relationships with RET Status and Outcome

BACKGROUND MicroRNAs (miRNAs) are involved in the pathogenesis of human cancers, including medullary thyroid carcinoma (MTC). The aim of this study was to test the hypothesis that different miRNA profiles are related to RET status and prognosis in patients with hereditary MTC (hMTC) and sporadic MTC (sMTC). METHODS We analyzed the expression of nine miRNAs (miR-21, miR-127, miR-154, miR-224, miR-323, miR-370, miR-9*, miR-183, and miR-375) by quantitative real-time-polymerase chain reaction in 34 cases of sMTC, 6 cases of hMTC, and 2 cases of C-cell hyperplasia (CCH). We also analyzed the immunohistochemical expression of PDCD4, an miR-21 gene target. sMTC (n=34) was genotyped for somatic RET and RAS mutations. Disease status was defined on the basis of the concentration of serum calcitonin at the latest follow-up and other parameters as indicated in the results. RESULTS MTC and CCH were both characterized by a significant overexpression of the whole set of miRNAs (the increase being 4.2-fold for miR-21, 6.7-fold for miR-127, 8.8-fold for miR-154, 6.6-fold for miR-224, 5.8-fold for miR-323, 6.1-fold for miR-370, 13-fold for miR-9*, 6.7-fold for miR-183, and 10.1 for miR-375, p<0.0001). PDCD4 expression was significantly downregulated in MTC samples, consistent with miR-21 upregulation. Significantly lower miR-127 levels were observed in sMTC carrying somatic RET mutations in comparison to sMTC carrying a wild-type RET. In sMTC and familial MTC, the miR-224 upregulation correlated with the absence of node metastases, lower stages at diagnosis, and with biochemical cure during follow-up. CONCLUSIONS miRNAs are significantly dysregulated in MTC, and this dysregulation is probably an early event in C-cell carcinogenesis. miR-224 upregulation could represent a prognostic biomarker associated with a better outcome in MTC patients.

Open versus endoscopic adrenalectomy in the treatment of localized (stage I/II) adrenocortical carcinoma: results of a multiinstitutional Italian survey

BACKGROUND We compared the oncologic effectiveness of open adrenalectomy and endoscopic adrenalectomy in the treatment of patients with localized adrenocortical carcinoma. METHODS One hundred fifty-six patients with localized adrenocortical carcinoma (stage I/II) who underwent R0 resection were included in an Italian multiinstitutional surgical survey. They were divided into 2 groups based on the operative approach (either conventional or endoscopic). RESULTS One hundred twenty-six patients underwent open adrenalectomy and 30 patients underwent endoscopic adrenalectomy. The 2 groups were well matched for age, sex, lesion size, and stage (P = NS). The mean follow-up time was similar for the 2 groups (P = NS). The local recurrence rate was 19% for open adrenalectomy and 21% for endoscopic adrenalectomy, whereas distant metastases were recorded in 31% of patients in the conventional adrenalectomy group and 17% in the endoscopic adrenalectomy group (P = NS). The mean time to recurrence was 27 ± 27 months in the conventional open adrenalectomy group and 29 ± 33 months in the endoscopic adrenalectomy group (P = NS). No significant differences were found between the 2 groups in terms of 5-year disease-free survival (38.3% vs 58.2%) and 5-year overall survival rates (48% vs 67%; P = NS). CONCLUSION The operative approach does not affect the oncologic outcome of patients with localized adrenocortical carcinoma, if the principles of surgical oncology are respected.

99mTc-MIBI radio-guided minimally invasive parathyroidectomy: experience with patients with normal thyroids and nodular goiters.

The surgical approach to primary hyperparathyroidism (HPT) is changing. In patients with a high probability to be affected by a solitary parathyroid adenoma (PA), a unilateral neck exploration (UNE) or a minimally invasive radio-guided surgery (MIRS) using the intraoperative gamma probe (IGP) technique have recently been proposed. We investigated the role of IGP in a group of 84 patients with primary HPT who were homogeneously evaluated before surgery by a single-day imaging protocol including 99mTcO4/MIBI subtraction scan and neck ultrasound (US) and then operated on by the same surgical team. Quick parathyroid hormone (QPTH) was intraoperatively measured in all cases to confirm successful parathyroidectomy. In 70 patients with scan/US evidence of a single enlarged parathyroid gland (EPG) and with a normal thyroid gland, MIRS was planned. In the other 14 patients, the IGP technique was utilized during a standard bilateral neck exploration (BNE) because of the presence of concomitant nodular goiter (11 cases) or multiglandular disease (MGD) (3 cases). The IGP technique consisted of the following: (1) in the operating room, a low 99mTc-MIBI dose (37 MBq) was injected intravenously during anesthesia induction; (2) subsequently, the patients neck was scanned with the probe by the surgeon to localize the cutaneous projection of the EPG; (3) in patients who underwent MIRS, the EPG was detected intraoperatively with the probe and removed through a small, 2 to 2.5 cm skin incision; (4) radioactivity was measured on the EPG both in vivo and ex vivo, the thyroid, the background and the parathyroid bed after EPG removal. In patients with concomitant nodular goiter, the radioactivity was also measured on the thyroid nodules. Surgical and pathologic findings were consistent with a single PA in 78 patients, parathyroid carcinoma in 2, and MGD in 4. MIRS was successfully performed in 67 of the 70 patients (97.7%) in whom this approach was planned. It must be pointed out that the IGP technique was particularly useful in detecting the PAs located in ectopic site (5 in the upper mediastinum, 2 at the carotid bifurcation) and deep in the neck (6 in the paratracheal/paraesophageal space). Moreover, MIRS was also successfully performed in the seven patients who had undergone previous parathyroid or thyroid surgery. In the other 3 of 70 patients (4.3%), a conversion to BNE was required because a parathyroid carcinoma (2 cases) and a MGD (1 case) were diagnosed during surgical intervention. It is worth noting that in this latter patient affected by MGD, in contrast with the other patients from our series, QPTH remained elevated after the removal of the preoperatively visualized EPG suggesting the persistence of occult hyperfunctioning parathyroid tissue, and another contralateral EPG was found at BNE. Regarding the group of patients in whom a BNE was planned, the IGP helped the surgeon to localize a supernumerary EPG ectopic in the thymus in a patient with MGD, and to localize a PA ectopic to the right carotid bifurcation in a patient with nodular goiter. However, it has to be pointed out that it was difficult for the surgeon to differentiate intraoperatively with the probe the radioactivity of the EPG from that of thyroid nodule(s) in the other 10 patients with HPT with a concomitant nodular goiter, particularly in 6 patients in whom 99mTc-MIBI uptake was higher in thyroid nodule(s) than in EPG. On the basis of these data we can conclude that: (1) in patients with primary HPT with a high scan/US probability to be affected by a single PA and with a normal thyroid gland, IGP appears to be an useful technique with the aim of performing MIRS; (2) a 99mTc-MIBI dose as low as 37 MBq appears to be adequate to successfully perform MIRS; (3) the measurement of QPTH is strongly recommended in patients with HPT selected for MIRS to confirm complete removal of hyperfunctioning parathyroid tissue; (4) MIRS can be useful also in patients with HPT who previously received parathyroid/thyroid surgery with the aim of limiting surgical trauma at reoperation and minimizing the related risk of complications; (5) with the exception of PA located in ectopic sites, IGP does not seem to be a recommendable technique in patients with HPT concomitant nodular goiter.