Frequent Loss of Heterozygosity on Chromosomes 3p and 17p without VHL or p53 Mutations Suggests Involvement of Unidentified Tumor Suppressor Genes in Follicular Thyroid Carcinoma1
Follicular thyroid carcinoma (FTC) exhibits frequent loss of heterozygosity (LOH) on chromosomes 10q and 3p, suggesting involvement of tumor suppressor genes. We screened 14 FTC (10 Hurthle cell carcinomas and 4 nonoxyphilic FTC), 14 papillary thyroid carcinomas, and 7 follicular adenomas for LOH on chromosome arms 1p, 3p, 3q, 10p, 10q, 11p, 11q, 13q, 17p, and 17q. LOH was more frequent in FTC than in follicular adenoma or papillary thyroid carcinoma. In FTC, rates of LOH on 3p (86%), 17p (72%), and 10q (57%) were higher than the average rate of LOH (33%; P < 0.05). Most frequently involved were 3p21–25 and 17p13.1–13.3, the sites for the VHL (3p25–26) and p53 (17p13.1) tumor suppressors. We, therefore, characterized these genes by dideoxy fingerprinting and DNA sequencing. Two FTC had mutations in p53, but only 1 of these exhibited LOH at 17p. No VHL gene mutations were found. Thus, neither p53 nor VHL genes play a significant role in the pathogenesis of differentiated thyroid cancer. LOH on 17p, but not on 3p or 10q, was correlated with mortality. Accordingly, 3p and 10q LOH may represent early, and 17p LOH late, events in FTC development. The data suggest the presence of novel tumor suppressor genes on chromosomes 3p and 17p that may be important in the pathogenesis of FTC.
Pediatric Endocrine Surgery: A 20-Year Experience at the Mayo Clinic
AbstractBackgroundIntense postoperative monitoring has resulted in increasing detection of patients with recurrent papillary thyroid cancer (PTC). Our goals included quantifying successful reoperation, and analyzing surgical complications and reasons for relapse.MethodsFrom 1999 to 2008, a total of 410 patients underwent reoperation for PTC relapse. We analyzed post‐reoperative disease outcomes, reasons for relapse, and complications.ResultsBilateral reoperative thyroidectomy was performed in 13 (3 %) patients; lobectomy, 34 (8 %); central neck (VI) soft tissue local recurrence excision, 47 (11.5 %); bilateral VI node dissection, 107 (26 %); unilateral VI dissection, 112 (27 %); levels II–V dissection, 93 (23 %); levels III–V, 86 (21 %); lateral single‐ or two‐compartment dissection, 51 (12 %); and node picking, 20 (5 %) of level VI and 53 (13 %) lateral neck. Complications occurred in 6 %; including hypoparathyroidism, 3 %; unintentional recurrent laryngeal nerve (RLN) paralysis, 3 %; phrenic nerve injury, 0.5 %; spinal accessory nerve injury, 0.5 %; and chyle leak in 1.6 %. Of 380 (93 %) patients with follow‐up (mean 5.2 years); 274 (72 %) patients are alive with no structural evidence of disease, 38 % developed disease relapse (mean 2.1 years), 42 (11 %) died from PTC, and 55 (14 %) are alive with disease. The reason for relapse was a false negative pre‐reoperative ultrasound (US) in 18 (5 %), nodal recurrence in the operative field in 37 (10 %), a combination of these two reasons in 10 (3 %), and disease virulence (local or systemic recurrence) in 81 (21 %).ConclusionsAlthough 72 % of patients were rendered structurally disease free after reoperation, nearly 40 % suffered additional relapse. Improved surgical technique or preoperative localization might positively affect 15–20 %; at least 20 % reflect the biologic aggressiveness of the disease.
Primary Aldosteronism: Factors Associated with Normalization of Blood Pressure after Surgery
The development of subspecialty tumor groups for uncommon malignancies represents an effective approach to building experience, increasing patient volumes and referrals, and fostering development of increased therapeutic options and clinical trials for patients afflicted with otherwise historically neglected cancers.
Adrenalectomy Improves Outcomes of Selected Patients with Metastatic Carcinoma
AbstractBackgroundIndications and survival benefit for adrenalectomy (ADX) in the setting of metastasis are not clearly defined. We aimed to determine which patients with primary malignancies may benefit from ADX performed for metastasis. Mayo Clinic institutional outcomes in patients with metastatic disease to the adrenal(s) treated by adrenalectomy were compared to stage‐matched historical controls from the Surveillance Epidemiology and End Results (SEER) database.MethodsA retrospective review (1992–2010) was conducted to identify patients treated with ADX for metastatic cancer at Mayo Clinic, Rochester. Associations of clinical, surgical, and pathologic features with overall survival (OS) were evaluated using Cox proportional regression models. OS for those treated with ADX was compared with that for SEER database stage‐matched patients who underwent primary resection without resection of distant disease using log‐rank tests.ResultsA total of 166 patients underwent ADX for metastatic primaries involving the kidney 60, lung 24, sarcoma 19, colon 15, pancreas 13, and other‐35. Patients with sarcoma and kidney, lung, and pancreatic tumors who underwent ADX had better OS at 1, 2, and 3 years than did the SEER‐matched controls. Respectively, the rates were for sarcoma (100, 93, 86% vs. 57, 36, 30%), kidney (86, 80, 72% vs. 55, 37, 27%), lung (91, 69, 52% vs. 52, 34, 25%), and pancreas (79, 56, 45% vs. 33, 20, 12%). Univariate analysis identified primary diagnosis <2 years before ADX, other distant site, pancreatic primary, palliative operation, and persistent disease as risk factors for death.ConclusionsAn aggressive surgical approach results in improved OS in patients with metastatic disease arising from soft tissues, kidney, lung, and pancreas. Other tumors may benefit, but larger study cohorts are needed for a meaningful comparison.
Setting the Bar for Laparoscopic Resection of Sporadic Insulinoma
AbstractBackgroundLaparoscopic insulinoma resection (LIR) for sporadic disease is increasingly supported as a feasible and safe operation in small series of patients. To determine whether LIR is an acceptable alternative to the open operation, it is necessary to compare LIR to historical controls. The purpose of this study was to identify the skills and technology needed for LIR and establish outcome standards.MethodsA database of patients with benign sporadic insulinoma who underwent an open procedure at the Mayo Clinic was reviewed for demographics, imaging, operative/pathology reports, and outcomes. Outcomes were compared to a world‐wide meta‐analysis of patients who had undergone LIR reported in the English literature between 1996 and 2009.ResultsTwo hundred fifteen patients underwent a primary open operation for benign sporadic insulinoma. Solitary tumors were found in 97%. Meta‐analysis identified 232 patients who underwent LIR. The open and LIR groups underwent comparable operations that included enucleations (64 vs. 68%) and distal pancreatectomies (28 vs. 35%) (p = 0.06). The mean estimated blood loss, operating time, and length of stay were comparable between the open and LIR groups (p = NS). Pancreatic fistula occurred more often in the LIR group (24 vs. 11%, p < 0.05). A curative operation was performed in 98% of control patients and in 99% of the LIR group (p = NS).ConclusionsMultiple insulinomas are rare and a focused resection guided by imaging may be performed. LIR is associated with an increased incidence of pancreatic fistula. Success of LIR will depend on accurate multimodality preoperative imaging, skilled use of lap‐US to replace palpation for localization, and safe methods to dissect the tumor adjacent to the pancreatic duct.
Enhanced Survival in Locoregionally Confined Anaplastic Thyroid Carcinoma: A Single-Institution Experience Using Aggressive Multimodal Therapy
Background: Historical outcomes in anaplastic thyroid carcinoma (ATC) are poor, with a median survival of only 5 months and <20% of patients surviving 1 year from diagnosis. We hypothesized that survival in newly diagnosed patients with stages IVA and IVB locoregionally confined ATC might be improved by utilizing an aggressive therapeutic approach, prioritizing both the eradication of disease in the neck and preemptive treatment of occult metastatic disease. Methods: Between January 1, 2003, and December 31, 2007, 25 new ATC patients were evaluated at our institution. Of these 25 patients, 10 (40%) had metastatic disease at diagnosis and therefore underwent palliative treatment, whereas 5 (20%) had regionally confined disease and desired treatment at their local medical facilities. The remaining 10 consecutive patients (40%) had regionally confined ATC and elected aggressive therapy combining individualized surgery (where feasible), intensity-modulated radiation therapy (IMRT), and radiosensitizing + adjuvant chemotherapy intending four cycles of docetaxel + doxorubicin. Outcomes were assessed on an intention to treat basis. Results: There were no deaths from therapy, but hospitalization was required in two patients (20%) because of treatment-related adverse events. Five patients (50%) are alive and cancer-free, all having been followed >32 months (range: 32–89 months; median: 44 months) with a median overall Kaplan–Meier survival of 60 months. Overall survival at 1 and 2 years was 70% and 60%, respectively, compared to <20% historical survival at 1 year in analogous patients previously treated with surgery and conventional postoperative radiation at our and other institutions. Conclusions: Although based upon a small series of consecutively treated patients, an aggressive approach combining IMRT and radiosensitizing plus adjuvant chemotherapy appears to improve outcomes, including survival in stages IVA and IVB regionally confined ATC, but remains of uncertain benefit in patients with stage IVC (metastatic) disease. Also uncertain is the optimal chemotherapy regimen to use in conjunction with IMRT. Further multicenter randomized trials are required to define optimal therapy in this rare but deadly cancer.