BACKGROUNDThe authors proposed to determine risk factors associated with postoperative progression of parathyroid carcinoma within the neck (locoregional) and to assess the efficacy of postoperative adjuvant radiation therapy in preventing disease progression within the neck.METHODSA retrospective review of patients with pathologically confirmed parathyroid carcinoma who underwent surgical resection was performed. Risk factors identified on univariate analysis were applied in a proportional hazards analysis to identify significant independent predictors of locoregional disease progression and cause‐specific survival after surgical resection. Fifty‐seven patients were treated with surgery alone (no adjuvant radiation therapy [RT]) and were determined to have sufficient follow‐up and pathologically confirmed features to be included in the current analysis. Four patients were treated with surgery and adjuvant RT. Four patients received RT to the neck and mediastinum for unresectable locoregional disease progression. Patients were followed for a median of 75.6 months (range, 8.4–358 months).RESULTSTwenty‐five patients (44%) developed locoregional disease progression at a median of 27.1 months after surgery (range, 6.2–138.3 months). The univariate analysis revealed that surgical margin status and the institution at which the initial surgery was performed were predictive of locoregional progression‐free survival. The institution at which the initial surgery was performed was found to be an independent predictor of cause‐specific survival. Of the four patients treated with surgery and adjuvant RT, all were alive and without disease at the time of last follow‐up. All four patients who received RT for locoregional disease progression after initial surgery achieved locoregional disease control.CONCLUSIONSPatients with parathyroid carcinoma are reported to have a significant risk of locoregional disease progression after surgery alone. The results of the current study demonstrated that the risk of postoperative disease progression can be predicted by surgical margin status and the institution at which the initial surgery is performed. Patients treated with surgery and postoperative RT may have a lower risk of locoregional disease progression and improved cause‐specific survival. RT can be used to provide locoregional control of recurrent disease. Cancer 2003. © 2003 American Cancer Society.
Hepatitis C-associated osteosclerosis (HCAO) is a rare disorder characterized by a marked increase in bone mass during adult life. Despite the rarity of HCAO, understanding the mediator(s) of the skeletal disease is of great interest. The IGFs-I and -II have potent anabolic effects on bone, and alterations in the IGFs and/or IGF-binding proteins (IGFBPs) could be responsible for the increase in bone formation in this disorder. Thus, we assayed sera from seven cases of HCAO for IGF-I, IGF-II, IGF-IIE (an IGF-II precursor), and IGFBPs. The distribution of the serum IGFs and IGFBPs between their ternary ( ف 150 kD) and binary ( ف 50 kD) complexes was also determined to assess IGF bioavailability.HCAO patients had normal serum levels of IGF-I and -II, but had markedly elevated levels of IGF-IIE. Of the IGFBPs, an increase in IGFBP-2 was unique to these patients and was not found in control hepatitis C or hepatitis B patients. IGF-I and -II in sera from patients with HCAO were carried, as in the case of sera from control subjects, bound to IGFBP-3 in the ف 150-kD complex, which is retained in the circulation. However, IGF-IIE was predominantly in the ف 50-kD complex in association with IGFBP-2; this complex can cross the capillary barrier and access target tissues. In vitro, we found that IGF-II enhanced by over threefold IGFBP-2 binding to extracellular matrix produced by human osteoblasts and that in an extracellular matrix-rich environment, the IGF-II/IGFBP-2 complex was as effective as IGF-II alone in stimulating human osteoblast proliferation. Thus, IGFBP-2 may facilitate the targeting of IGFs, and in particular IGF-IIE, to skeletal tissue in HCAO patients, with a subsequent stimulation by IGFs of osteoblast function. Our findings in HCAO suggest a possible means to increase bone mass in patients with osteoporosis. (
Whether calcitonin deficiency causes and calcitonin excess prevents bone loss is controversial. We therefore measured plasma calcitonin levels and bone mineral density at the radius (by single photon absorptiometry) and lumbar spine (dual photon absorptiometry) in patients with an excess or deficiency of calcitonin. We studied 21 patients who had undergone subtotal thyroidectomy 6.8 to 29 years previously and had no calcitonin secretory reserve, and 11 patients who had received a diagnosis of medullary thyroid carcinoma 6.8 to 23 years previously and had chronic hypercalcitoninemia. Bone-density values, expressed as Z-scores (i.e., as the number of standard deviations above or below the normal means adjusted for age and sex), were indistinguishable from normal in the patients who had undergone thyroidectomy (means +/- SE: radius, 0.36 +/- 0.15; spine, 0.27 +/- 0.17). In the patients with medullary thyroid cancer, radial bone-density values were normal (-0.26 +/- 0.39), but spinal density was significantly reduced (-0.75 +/- 0.17, P less than 0.01). There were no significant correlations between the duration of calcitonin excess or deficiency and the bone density at either site. Bone mineral density was not affected by whether or not thyroxine replacement therapy was given. We conclude that skeletal mass is not affected by endogenous plasma calcitonin in adults.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.