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Impact of prophylactic central neck lymph node dissection on early recurrence in papillary thyroid carcinoma

Moo, Tracy-Ann; McGill, Julie; Allendorf, John; Lee, James; Fahey, Thomas; Zarnegar, Rasa
BACKGROUND:Although the role of prophylactic central neck lymph node dissection (CNLD) in the treatment of papillary thyroid carcinoma (PTC) is controversial, many surgeons perform routine prophylactic CNLD. The present study compares local recurrence rates in PTC patients undergoing total thyroidectomy with and without prophylactic CNLD. MATERIALS AND METHODS/METHODS:A retrospective review of 206 patients undergoing thyroidectomy for PTC was conducted at two tertiary referral centers. Of these, 81 patients had total thyroidectomy for PTC and a follow-up between 2 and 9 years with a mean of 3.1 years. Of these 81 patients, 45 underwent routine prophylactic CNLD and 36 did not. For those two groups, demographics, clinical and pathologic findings, radioactive iodine (RAI) treatment, and the incidence of recurrence were compared. Univariate statistical analysis was performed. RESULTS:There was no significant difference in age, gender, multifocality, or extrathyroidal extension for the two groups. Patients with CNLD had an average tumor size of 1.4 cm versus 2 cm in the group without CNLD (p < 0.05). Patients who underwent CNLD had an average of 8 nodes removed, and positive nodes were found in 33%. Patients with CNLD received a higher dose of RAI, 102.7 mCi versus 66.3 mCi (p < 0.05). The incidence of positive nodes correlated with an increased RAI dose (r = 0.55). Rates of parathyroid removal and autotransplantation were higher in the CNLD group, 36 and 16% in the CNLD group versus 22 and 3% in the group without CNLD (p = 0.4 and p = 0.07). Rates of temporary hypocalcemia were higher in the CNLD group (31 versus 5%; p = 0.001), however rates of permanent hypocalcemia were similar, 1/35 in the no CNLD group versus 0/45 in the CNLD group (p = 0.4). There was a higher recurrence rate among patients without CNLD 6/36 (16.7%) versus 2/45 (4.4%), although this difference was not statistically significant (p = 0.13). CONCLUSIONS:Routine CNLD as an adjunct to total thyroidectomy identifies positive nodes in over 30% of patients with PTC. The discovery of positive nodes is associated with higher doses of RAI for postoperative ablation, and there is a trend toward decreased recurrence in patients undergoing CNLD.
PMID: 20130868
ISSN: 1432-2323
CID: 3487262

World wide what? The quality of information on parathyroid disease available on the Internet

McGill, Julie F; Moo, Tracy-Ann; Kato, Meredith; Hoda, Raza; Allendorf, John D; Inabnet, William B; Fahey, Thomas J; Brunaud, Laurent; Zarnegar, Rasa; Lee, James A
BACKGROUND:Patients are relying on the Internet with greater frequency to learn about diseases and make medical decisions. We hypothesized that there is a disparity between the perceptions of patients and those of surgeons regarding the quality of information about primary hyperparathyroidism on the Internet. METHODS:Patients (n = 62) with primary hyperparathyroidism seen in endocrine surgery clinics in France and the United States responded to a survey regarding their use of the Internet to prepare for upcoming parathyroid surgery. A panel of endocrine surgeons reviewed the top "hits" retrieved from Web sites related to parathyroid disease. Sites were rated using a previously validated Web site quality scoring system. RESULTS:A total of 75% of the American cohort and 53% of the French cohort used the Internet to prepare for parathyroid surgery. The majority of these patients reported that the information was "somewhat to very accurate." The panel of surgeons gave the Web sites an overall average qualitative score of 8.6 (53%). CONCLUSION/CONCLUSIONS:Surgeons and patients have different perceptions as to what constitutes a high-quality Web site. As patients depend more on the Internet to prepare for parathyroid surgery, there is an opportunity and a clear need to create comprehensive, high-quality, patient-oriented Web sites on this topic.
PMID: 19958939
ISSN: 1532-7361
CID: 3486922

Molecular analysis of PIK3CA, BRAF, and RAS oncogenes in periampullary and ampullary adenomas and carcinomas

Schönleben, Frank; Qiu, Wanglong; Allendorf, John D; Chabot, John A; Remotti, Helen E; Su, Gloria H
BACKGROUND:Mutations of KRAS are known to occur in periampullary and ampullary adenomas and carcinomas. However, nothing is known about NRAS, HRAS, BRAF, and PIK3CA mutations in these tumors. While oncogenic BRAF contributes to the tumorigenesis of both pancreatic ductal adenocarcinoma and intraductal papillary mucinous neoplasms/carcinomas (IPMN/IPMC), PIK3CA mutations were only detected in IPMN/IPMC. This study aimed to elucidate possible roles of BRAF and PIK3CA in the development of ampullary and periampullary adenomas and carcinomas. METHODS:Mutations of BRAF, NRAS, HRAS, KRAS, and PIK3CA were evaluated in seven adenomas, seven adenomas with carcinoma in situ, and 21 adenocarcinomas of the periampullary duodenal region and the ampulla of Vater. Exons 1 of KRAS; 2 and 3 of NRAS and HRAS; 5, 11, and 15 of BRAF; and 9 and 20 of PIK3CA were examined by direct genomic sequencing. RESULTS:In total, we identified ten (28.6%) KRAS mutations in exon 1 (nine in codon 12 and one in codon 13), two missense mutations of BRAF (6%), one within exon 11 (G469A), and one V600E hot spot mutation in exon 15 of BRAF. BRAF mutations were present in two of five periampullary tumors. All mutations appear to be somatic since the same alterations were not detected in the corresponding normal tissues. CONCLUSION/CONCLUSIONS:Our data provide evidence that oncogenic properties of KRAS and BRAF but not NRAS, HRAS, and PIK3CA contribute to the tumorigenesis of periampullary and ampullary tumors; BRAF mutations occur more frequently in periampullary than ampullary neoplasms.
PMID: 19440799
ISSN: 1873-4626
CID: 3486852

Negative preoperative localization leads to greater resource use in the era of minimally invasive parathyroidectomy

Harari, Avital; Allendorf, John; Shifrin, Alexander; DiGorgi, Mary; Inabnet, William B
BACKGROUND:Successful preoperative localization plays an important role in patient selection for focused parathyroidectomy. METHODS:The case records of 499 consecutive patients with presumed hyperparathyroidism who underwent neck exploration were reviewed. Positive imaging patients (n = 373) had a localizing study that clearly showed a single abnormal parathyroid gland whereas negative imaging patients (n = 44) failed to localize or had discordant imaging results. RESULTS:Positive imaging patients were more likely to have a single adenoma (93.0% vs 72.1%; P < .001), and were less likely to require a bilateral exploration (8.1% vs 70.4%; P < .001). Negative imaging patients required more frozen sections (.9 +/- 1.3 vs .2 +/- .7; P < .001), and longer surgical time (77.3 +/- 52.5 min vs 48.4 +/- 34.6 min; P < .001). The cure rate was significantly higher in the positive imaging group (96.0% vs 87.1%; P < .03), with no difference in the incidence of complications (3.2% vs 2.3%; P value was not significant). CONCLUSIONS:Patients with unsuccessful or discordant preoperative localization have a higher incidence of multigland disease, lower cure rate, and consume more institutional resources than patients with successful preoperative localization.
PMID: 19249736
ISSN: 1879-1883
CID: 3487252

Reconstruction of the replaced right hepatic artery at the time of pancreaticoduodenectomy

Allendorf, John D; Bellemare, Sarah
BACKGROUND:The arterial anatomy supplying the liver is highly variable. One of the most common variants is a completely replaced right hepatic artery which is seen in about 11% of the population. Interruption of arterial flow to the right hepatic artery at the time of pancreaticoduodenectomy has been associated with biliary fistula and the consequent complications, as well as stenosis of the biliary enteric anastomosis. Malignancies of the posterior aspect of the head of the pancreas can encase a replaced right hepatic artery without involvement of other vascular structures. In this situation, it is possible to resect and reconstruct the replaced right hepatic artery to maintain oxygen delivery to the biliary enteric anastomosis. SUMMARY/CONCLUSIONS:Herein we describe a technique to reconstruct a replaced right hepatic artery following resection of the vessel en bloc with the tumor during a pancreaticoduodenectomy, using inflow from the gastroduodenal artery.
PMID: 18642051
ISSN: 1873-4626
CID: 3486842

Revisiting metastatic adult pancreatoblastoma. A case and review of the literature [Case Report]

Charlton-Ouw, Kristofer M; Kaiser, Christy L; Tong, Guo Xia; Allendorf, John D; Chabot, John A
UNLABELLED:CONTEX: Most cases of pancreatoblastoma, a rare tumor of neuroendocrine origin, are seen in the pediatric population. To date, at least sixteen case reports have been described of pancreatoblastoma in patients 19-year old or older. Surgical resection is the mainstay of curative treatment. Even patients with liver metastasis can have long-term disease-free survival. CASE REPORT/METHODS:One recent example is a 33-year-old male who presented to us for a right hepatic lobectomy for removal of the presumed primary tumor - later discovered to be a metastasis - followed by pancreaticoduodenectomy for resection of the true primary lesion. Five years after resection, this patient is the longest disease-free survivor of metastatic adult pancreatoblastoma. CONCLUSION/CONCLUSIONS:We review the literature and propose that resection of pancreatoblastoma can offer long-term disease-free survival even with liver metastasis and microscopically-positive surgical margins.
PMID: 18981556
ISSN: 1590-8577
CID: 3486912

Mutational analyses of multiple oncogenic pathways in intraductal papillary mucinous neoplasms of the pancreas

Schönleben, Frank; Allendorf, John D; Qiu, Wanglong; Li, Xiaojun; Ho, Daniel J; Ciau, Nancy T; Fine, Robert L; Chabot, John A; Remotti, Helen E; Su, Gloria H
OBJECTIVE:There is much accumulated evidence that EGFR, HER2, and their downstream signaling pathway members such as KRAS, BRAF, and PIK3CA are strongly implicated in cancer development and progression. Recently, mutations in the kinase domains of EGFR and HER2, associated with increased sensitivity to tyrosine kinase inhibitors, have been described. METHODS:To evaluate the mutational status of these genes in intraductal papillary mucinous neoplasm (IPMN)/intraductal papillary mucinous carcinoma (IPMC), EGFR and HER2 were analyzed in 36 IPMN/IPMC, and the results were correlated to the mutational status of the KRAS, BRAF, and PIK3CA genes in the samples. RESULTS:Together, we identified 1 silent mutation of HER2, 17 (43%) KRAS mutations, 1 (2.7%) BRAF mutation, and 4 (11%) mutations of PIK3CA in the IPMN/IPMC samples. CONCLUSIONS:The EGFR and ERBB2 (HER2) mutations are very infrequent in IPMN/IPMC, suggesting the limited possibility of targeting mutated ERBB2 and EGFR for therapy for these lesions. The KRAS, BRAF, and PIK3CA, however, could represent interesting targets for future therapies in these lesions.
PMID: 18376308
ISSN: 1536-4828
CID: 3486902

Neoadjuvant chemotherapy and radiation for patients with locally unresectable pancreatic adenocarcinoma: feasibility, efficacy, and survival

Allendorf, John D; Lauerman, Margaret; Bill, Aliye; DiGiorgi, Mary; Goetz, Nicole; Vakiani, Efsevia; Remotti, Helen; Schrope, Beth; Sherman, William; Hall, Michael; Fine, Robert L; Chabot, John A
BACKGROUND:We evaluated the feasibility and efficacy of neoadjuvant chemotherapy and radiation for patients with locally unresectable pancreatic cancer. MATERIALS AND METHODS/METHODS:From October 2000 to August 2006, 245 patients with pancreatic adenocarcinoma underwent surgical exploration at our institution. Of these, 78 patients (32%) had undergone neoadjuvant therapy for initially unresectable disease, whereas the remaining patients (serving as the control group) were explored at presentation (n=167). All neoadjuvant patients received gemcitabine-based chemotherapy, often in conjunction with docetaxal and capecitabine in a regimen called GTX (81%). Seventy-five percent of neoadjuvant patients also received preoperative abdominal radiation (5,040 rad). RESULTS:Neoadjuvant patients were younger than control-group patients (60.8 vs 66.2 years, respectively, p<0.002). Seventy-six percent of neoadjuvant patients were resected as compared to 83% of control patients (NS). Concomitant vascular resection was required in 76% of neoadjuvant patients but only 20% of NS (p<0.01). Complications were more frequent in the neoadjuvant group (44.1 vs 30.9%, p<0.05), and mortality was higher (10.2 vs 2.9%, p<0.03). Among the neoadjuvant patients, all but one of the deaths were in patients that underwent arterial reconstruction. Mortality for patients undergoing a standard pancreatectomy without vascular resection was 0.8% in this series. Of patients resected, negative margins were achieved in 84.7% of neoadjuvant patients and 72.7% of NS. Within the cohort of neoadjuvant patients, radiation significantly increased the complication rate (13.3 vs 54.6%, p<0.006), but did not affect median survival (512 vs 729 days, NS). Median survival for patients who received neoadjuvant therapy (503 days) was longer than NS that were found to be unresectable at surgery (192 days, p<0.001) and equivalent to NS that were resected (498 days). CONCLUSIONS:Resection rate, margin status, and median survivals were equivalent when neoadjuvant patients were compared to patients considered resectable by traditional criteria, demonstrating equal efficacy. Surgical resection with venous reconstruction following neoadjuvant therapy for patients with locally advanced pancreatic cancer can be performed with acceptable morbidity and mortality. This approach extended the boundaries of surgical resection and greatly increased median survival for the "inoperable" patient with advanced pancreatic cancer.
PMID: 17786524
ISSN: 1091-255x
CID: 3486892

1112 consecutive bilateral neck explorations for primary hyperparathyroidism

Allendorf, John; DiGorgi, Mary; Spanknebel, Kathryn; Inabnet, William; Chabot, John; Logerfo, Paul
BACKGROUND:Bilateral neck exploration has been the standard approach for patients with primary hyperparathyroidism. Improved localization studies and the availability of intraoperative parathyroid hormone monitoring have challenged the necessity of four-gland exploration. In this series we report a single surgeon's experience with bilateral neck exploration for primary hyperparathyroidism in an effort to establish benchmark outcomes from which to evaluate minimally invasive protocols. METHODS:The charts of 1112 consecutive patients who underwent neck exploration for primary hyperparathyroidism by a single surgeon over a 17-year period were reviewed. All patients underwent bilateral neck exploration under either general (n = 264) or local (n = 848) anesthesia. RESULTS:The overall cure rate was 97.4% with a complication rate of 3.4%. Morbidity included recurrent laryngeal nerve injury (0.2%), postoperative bleeding (0.8%), and transient hypocalcemia (1.8%). There was no mortality. Overall mean operating time was 52.5 +/- 30.2 minutes. A single gland was removed in 78.4% of patients, and 22.3% of patients underwent concomitant thyroidectomy. The cure rate was lower for patients undergoing reexploration (89.2% vs. 97.9%, p < 0.05). Choice of anesthetic approach did not affect the cure or complication rate. The overall conversion rate from local to general anesthesia was 1.5%. Patients undergoing general anesthesia were operated on earlier in the series and were less likely to be managed on an ambulatory basis (local 87.5% vs. general 38.4%, p < 0.05). During the last 5 years of the series, more than 90% of patients underwent exploration under local anesthesia. CONCLUSION/CONCLUSIONS:This large modern series of neck explorations for primary hyperparathyroidism confirms the safety, feasibility, and efficacy of the bilateral approach. It further demonstrates that individual surgeons can achieve outcomes equivalent to those with four-gland explorations under local anesthesia.
PMID: 17768656
ISSN: 0364-2313
CID: 3487242

The effects of surgical trauma on colorectal liver metastasis

Georges, C; Lo, T; Alkofer, B; Whelan, R; Allendorf, J
PMID: 17522938
ISSN: 1432-2218
CID: 3487232