The coming of age of radiation-induced hyperparathyroidism: evolving patterns of thyroid and parathyroid disease after head and neck irradiation

Thyroidectomy with and without laryngectomy: Differences in post-operative hypocalcemia and management

BACKGROUND

Total laryngectomy (TL) with thyroidectomy can pose significant risks to parathyroid function, and variance in rates of post-operative hypocalcemia (POH) based on extent of thyroidectomy have not been previously reported. Our objective is to identify the rates of hypocalcemia and hypoparathyroidism in TL+/-thyroidectomy and compare this to matched thyroidectomy alone cohorts.

METHODS

Multi-institutional retrospective chart review of patients treated surgically for laryngeal cancer with TL or benign/malignant thyroid disease with thyroidectomy at regional tertiary care centers in New Orleans and Baton Rouge, Louisiana from 2016 to 2019. Cases were evaluated for post-operative and post-discharge calcium and parathyroid hormone levels, post-operative and long-term calcium supplementation, and intraoperative parathyroid identification and management.

RESULTS

101 TL and 319 thyroidectomy patients' charts were reviewed. Regression analysis revealed increased odds of hypocalcemia and hypoparathyroidism in TL + TT versus TT alone (OR 10.7, OR 16.5, p < 0.001, respectively). TL + HT versus HT alone had increased odds of hypoparathyroidism (OR 1.6, p < 0.001). TL with any thyroidectomy compared to TL alone demonstrated both increased odds of hypocalcemia and hypoparathyroidism (OR 4.4 p = 0.009, and OR 4.5 p = 0.05). Odds of requiring long-term calcium supplementation were significantly increased with the addition of thyroidectomy across all groups. TL + TT was 8 times as likely (p = 0.002) and TL + HT was 5.3 times as likely (p = 0.001) to require long-term calcium supplementation compared to TL alone.

CONCLUSIONS

Thyroidectomy combined with TL demonstrates marked increased risk of parathyroid dysfunction and resultant POH. Despite improved visualization of soft tissue anatomy with TL, risk of parathyroid injury in these settings requires special attention to extent of parathyroid dissection and potential devascularization to reduce long-term sequelae of hyperparathyroidism. Therefore, post-operative calcium monitoring after TL is necessary and should resemble the long-standing stringent protocols that already exist for monitoring in thyroidectomy populations.

CLINICAL-METABOLIC AND HORMONAL RELATIONSHIPS BETWEEN PARATHYROID DISEASE AND OTHER NON-CANCEROUS ENDOCRINE DISORDERS IN THE CHORNOBYL NPP ACCIDENT SURVIVORS

OBJECTIVE

to investigate the clinical, hormonal-metabolic and structural features of parathyroid injuries in sur-vivors exposed to ionizing radiation after the Chornobyl NPP accident in adulthood and childhood, both with theirconnections to other non-cancerous endocrine disorders, and to establish the respective interhormonal and dys-metabolic relationships.

MATERIALS AND METHODS

Clinical effects of ionizing radiation on the endocrine system in persons affected by theChornobyl NPP accident (n = 224) and their descendants (n = 146), compared with the general population sample(n = 70) were the study object. All patients underwent the ultrasound thyroid and parathyroid examination. Thegenerally recognized clinical, anthropometric (body weight, height, thigh volume, body mass index), instrumental(ultrasound examination of thyroid and parathyroid glands), laboratory (biochemical, hormonal), and statisticalmethods were applied. Parametric and nonparametric statistical methods were used in data processing. The value ofp < 0.05 was considered a statistically significant.

RESULTS

No significant difference was found in the incidence of carbohydrate metabolic disorders in the ChornobylNPP (ChNPP) accident consequences clean-up workers (ACCUW), evacuees from the NPP 30-km exclusion zone, res-idents of radiologically contaminated areas and in the control group in whom the parathyroid hyperplasia wasdetected. There was a significant increase in the incidence of arterial hypertension among ACCUW who had parathy-roid hyperplasia (76.9%) vs. the control group (51.2%). In cases of parathyoid hyperplasia the vitamin D levels weresignificantly lower than without it. Vitamin D insufficiency/deficiency was found in 94% of the surveyed subjects.The average level of parathyroid hormone in blood serum was significantly higher in the ACCUW of «iodine» period withdiagnosed parathyroid hyperplasia than in the control group: (57.2 ± 2.87) pg / ml against (32.74 ± 3.58) pg / ml,p < 0.05. Results of multivariative analysis indicated a strong association of vitamin 25(OH)D insufficiency/defi-ciency with development of thyroid disease, carbohydrate metabolic disorders, cardiovascular disease, osteo-penia/osteoporosis. parathyroid ultrasound scan was at that an effective diagnostic method for primary screeningfor parathyroid hyperplasia and regular monitoring of the treatment efficiency. When examining children bornto parents irradiated after the ChNPPA the parathyroid hyperplasia (58%) and low serum content of vitamin D(11.6 ± 3.5) nmol / l were most often found in children living on radiologically contaminated territories (RCT).A strong correlation was established between the HOMA insulin resistance index and serum content of vitamin D(r = 0.65), parathyroid hormone (r = 0.60), and free thyroxine (r = 0.68) in the group of children born to parents irra-diated after the ChNPPA, having got chronic autoimmune thyroiditis, which indicated a relationship between thy-roid function, impaired carbohydrate and fat metabolism and the state of parathyroids.

CONCLUSIONS

No difference in the incidence of carbohydrate metabolic disorders was found in the ChNPP ACCUW,evacuees from the 30-km exclusion zone, and residents of radiologically contaminated territories in whom parathy-roid hyperplasia was detected vs. the control group. Patients with parathyroid hyperplasia were found to be defi-cient in vitamin D in 94% of cases, and level of latter was significantly lower than under the normal parathyroid size.There was a significant increase in the incidence of diagnosed arterial hypertension among ACCUW who had parathy-roid hyperplasia vs. the control group: (76.9 ± 3.5)% vs. (51.2 ± 3.7)%. According to multivariate analysis a strongassociation between the vitamin 25(OH)D insufficiency/deficiency and development of thyroid disease, carbohydratemetabolic disorders, cardiovascular disease, and osteopenia/osteoporosis was established. The average level of pa-rathyroid hormone in the blood serum of the ChNPP ACCUW of the «iodine» period with diagnosed parathyroid hyper-plasia was significantly higher (57.2 ± 2.87) pg / ml against (32.74 ± 3.58) pg / ml; p <0,05) in the control group.

Parathyroid Hormone Level Changes Following Radioiodine Therapy for Thyroid Cancer: A Prospective Observational Study

OBJECTIVE

Our objective was to analyze the effect of radioiodine (RAI) therapy on parathyroid hormone (PTH) secretion.

METHODS

A total of 137 patients were included and divided into 2 groups based on pretherapy PTH levels. The residual thyroid tissue volume was classified into 4 grades (0-3), and a value of 0 indicated that there was no apparent residual tissue. We analyzed the PTH level changes among different time points in each group and the factors that could predict the PTH level changes.

RESULTS

In 113 patients with normal parathyroid gland function, the PTH level at baseline, 1 day, 7 days, 1 month, 3 months, and 6 months after RAI therapy did not show any significant difference; in 24 patients with decreased parathyroid gland function, the level of PTH immediately decreased after the implementation of RAI therapy but gradually returned to a pre-RAI therapy level within 6 months. On the seventh day after therapy, the mean value of PTH in patients with a residual thyroid tissue volume of extent of 0/1 was 8.0 ± 2.3 pg/mL, which was significantly higher than that in patients with a residual thyroid tissue volume of extent of 2/3 (P = .011). Similar phenomena were observed 1 month, 3 months, and 6 months after therapy.

CONCLUSION

RAI therapy had a significant transient adverse effect on parathyroid gland function in patients with decreased PTH secretion pretherapy, and the extent was associated with the amount of residual thyroid tissue.

Late side effects of radiation treatment for head and neck cancer

Patients undergoing radiation therapy for head and neck cancer (HNC) experience significant early and long-term side effects. The likelihood and severity of complications depends on a number of factors, including the total dose of radiation delivered, over what time it was delivered and what parts of the head and neck received radiation. Late side effects include: permanent loss of saliva; osteoradionecrosis; radiation recall myositis, pharyngoesophageal stenosis; dental caries; oral cavity necrosis; fibrosis; impaired wound healing; skin changes and skin cancer; lymphedema; hypothyroidism, hyperparathyroidism, lightheadedness, dizziness and headaches; secondary cancer; and eye, ear, neurological and neck structures damage. Patients who undergo radiotherapy for nasopharyngeal carcinoma tend to suffer from chronic sinusitis. These side effects present difficult challenges to the patients and their caregivers and require life-long strategies to alleviate their deleterious effect on basic life functions and on the quality of life. This review presents these side effects and their management.

EFFECT OF POST-SURGICAL RAI THERAPY ON PARATHYROID FUNCTION IN PATIENTS WITH DIFFERENTIATED THYROID CANCER

Objective: Radiotherapy with radioactive iodine (RAI) has become a common treatment for postsurgical differentiated thyroid carcinoma (DTC). The objective of this study was to determine the effect of RAI therapy following surgery on the function of the parathyroid glands in DTC patients. Methods: A total of 81 DTC patients who received RAI therapy after surgery were enrolled in the study. The size of the residual thyroid was detected by technetium-99m (^99mTc)-pertechnetate thyroid scan (^99mTc thyroid scan) before RAI therapy. The iodine uptake ability of residual thyroid was evaluated by iodine-131 (¹³¹I) whole-body scan (WBS). All patients were treated with an activity of 3.7 GBq (100 mCi) ¹³¹I. Parathyroid hormone (PTH), serum calcium, phosphorus, and magnesium were evaluated at 1 day before treatment, and at 1 month and 3 months after treatment. Results: The results show that there was no statistically significant difference in blood PTH level observed (P>.05) between 3 time points (pre-treatment, 1 month post-treatment and 3 months post-treatment). The serum calcium and phosphorus did not change significantly (P>.05), but serum magnesium level was elevated after treatment (P<.05). There were no significant differences between PTH changes and sex, age, scores of ^99mTc thyroid scan, scores of ¹³¹I WBS, Tumor (T) stage, and Node (N) stage. Conclusion: RAI therapy following surgery did not significantly affect parathyroid function in DTC patients. Abbreviations: ATA = American Thyroid Association; DTC = differentiated thyroid carcinoma; FT3 = free triiodothyronine; FT4 = free thyroxine; 131I = iodine-131; PTH = parathyroid hormone; RAI = radioiodine; 99mTc = Technetium-99m; TG = thyroglobulin; TNM = Tumor Node Metastasis; TSH = thyroid-stimulating hormone; WBS = whole-body scan.

Primary hyperparathyroidism: a retrospective study over 18 years in an oncology center

Aim: To study primary hyperparathyroidism (pHPT) in an oncology center, including its possible association with malignancy and ionizing radiation. Methods: Retrospective analysis of 188 patients with sporadic pHPT treated with parathyroidectomy between 2000 and 2018. We studied the etiology, clinical and biochemical features of pHPT, history of malignancies and exposure to radiotherapy. Results: pHPT was caused by parathyroid adenoma in 90.4%, hyperplasia in 5.3% and carcinoma in 4.3%. Cure and recurrence rates of pHPT were 99 and 4.3%, respectively. Median follow-up time was 19 months. Prevalence of malignancies was 30%, mostly thyroid and breast cancer. Radiotherapy of the head, neck or thorax (8.5%) was not associated with worse hypercalcaemia or recurrence. Males had larger adenomas, higher calcium and parathyroid hormone (p < 0.01). Conclusion: Prevalence of parathyroid carcinoma and other malignancies was higher than reported in other studies. Ionizing radiation exposure was unrelated with pHPT severity. Men had more severe pHPT. High cure and low recurrence rates were achieved.

Bone and hormonal status 10 years post-allogeneic bone marrow transplantation

Bone loss and endocrine dysfunction are potential late complications of allogeneic stem cell transplant (allo-SCT); however, scant information concerning the long-term effects in SCT adult patients is available. In the present study, we evaluated bone status, expressed as bone mineral density (BMD), and endocrine functions including PTH, TSH, free T4, testosterone, SHBG, FSH, LH, and IGF-1, in 20 adult leukemia patients >10 years after allo-SCT. A low BMD (Z score <-2.0) was observed in two patients; two patients had osteoporotic fractures, and two had a unilateral avascular necrosis of the femoral head. Elevated PTH was observed in 30% of patients, and 25-hydroxy vitamin D (25(OH)D) was low (<50 nmol/L) in 45% of the patients. The majority of the patients had thyroid tests within the reference range, while elevated FSH values were present in 8 of 12 males. We conclude that adult leukemia patients have relatively well-preserved BMD >10 years post-allo-SCT. Prophylactic treatment of osteoporosis should be individualized, but control of BMD is necessary for long-term follow-up. Control of PTH and vitamin D levels before and after allo-SCT is recommended, and vitamin D supplementation should be considered if indicated. Estrogen replacement therapy is a routine treatment in females, whereas gonadal function in males requires further investigation.

Long-Term Endocrine and Metabolic Consequences of Cancer Treatment: A Systematic Review

The number of patients surviving ≥5 years after initial cancer diagnosis has significantly increased during the last decades due to considerable improvements in the treatment of many cancer entities. A negative consequence of this is that the emergence of long-term sequelae and endocrine disorders account for a high proportion of these. These late effects can occur decades after cancer treatment and affect up to 50% of childhood cancer survivors. Multiple predisposing factors for endocrine late effects have been identified, including radiation, sex, and age at the time of diagnosis. A systematic literature search has been conducted using the PubMed database to offer a detailed overview of the spectrum of late endocrine disorders following oncological treatment. Most data are based on late effects of treatment in former childhood cancer patients for whom specific guidelines and recommendations already exist, whereas current knowledge concerning late effects in adult-onset cancer survivors is much less clear. Endocrine sequelae of cancer therapy include functional alterations in hypothalamic-pituitary, thyroid, parathyroid, adrenal, and gonadal regulation as well as bone and metabolic complications. Surgery, radiotherapy, chemotherapy, and immunotherapy all contribute to these sequelae. Following irradiation, endocrine organs such as the thyroid are also at risk for subsequent malignancies. Although diagnosis and management of functional and neoplastic long-term consequences of cancer therapy are comparable to other causes of endocrine disorders, cancer survivors need individually structured follow-up care in specialized surveillance centers to improve care for this rapidly growing group of patients.

Gcm2 regulates the maintenance of parathyroid cells in adult mice

Glial cells missing homolog 2 (GCM2), a zinc finger-type transcription factor, is essential for the development of parathyroid glands. It is considered to be a master regulator because the glands do not form when Gcm2 is deficient. Remarkably, Gcm2 expression is maintained throughout the fetal stage and after birth. Considering the Gcm2 function in embryonic stages, it is predicted that Gcm2 maintains parathyroid cell differentiation and survival in adults. However, there is a lack of research regarding the function of Gcm2 in adulthood. Therefore, we analyzed Gcm2 function in adult tamoxifen-inducible Gcm2 conditional knockout mice. One month after tamoxifen injection, Gcm2-knockout mice showed no significant difference in serum calcium, phosphate, and PTH levels and in the expressions of calcium-sensing receptor (Casr) and parathyroid hormone (Pth), whereas Ki-67 positive cells were decreased and terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) positive cell number did not change, as compared with those of controls. Seven months after tamoxifen injection, Gcm2-knockout mice showed shrinkage of the parathyroid glands and fewer parathyroid cells. A significant decrease was noted in Casr- and Pth-expressing cells and serum PTH and Ca levels, whereas serum phosphate levels increased, as compared with those of controls. All our results concluded that a reduction of Gcm2 expression leads to a reduction of parathyroid cell proliferation, an increase in cell death, and an attenuation of parathyroid function. Therefore, we indicate that Gcm2 plays a prominent role in adult parathyroid cell proliferation and maintenance.

The role of ultrasound in the diagnosis of the coexistence of primary hyperparathyroidism and non-medullary thyroid carcinoma

BACKGROUND

The coexistence of primary hyperparathyroidism(PHPT) and papillary thyroid cancer(PTC) is a known entity; it is a rare and complicated setting for diagnostic imaging.

METHODS

After reviewing clinical data of 112 patients who had been treated for PHPT in our facility between January 2015 and December 2017, we identified 7 non-medullary thyroid carcinoma (NMTC) (6.25%). All of them had taken an ultrasound scan and undergone operation. In addition, we have also reviewed relevant reports from other facilities addressing PHPT and NMTC (Mainly PTC).

RESULTS

The 7 NMTCs were all pathologically confirmed PTC in our study, and they consisted of 6 parathyroid adenomas and 1 parathyroid carcinoma. 1 of the 7 patients had 2 malignant PTC nodules with neck lymph node metastasis, the rest 6 had single-focal PTC. Processing previous report data supported an association between PHPT and PTC, although the coexistence of PHPT and PTC is rare, but it does happen. Ultrasound, as an effective examination, would help screen the simultaneous lesions before operation, thus to avoid second surgery if not observed for both diseases at initial stage.

CONCLUSIONS

Ultrasound is a necessary choice for preoperative localization, because it has the ability to simultaneously examine the thyroid and parathyroid lesions.

Primary Hyperparathyroidism: Effects on Bone Health

Primary hyperparathyroidism (PHPT) is the most common cause of chronic hypercalcemia. With the advent of routine calcium screening, the classic presentation of renal and osseous symptoms has been largely replaced with mild, asymptomatic disease. In hypercalcemia caused by PHPT, serum parathyroid hormone levels are either high, or inappropriately normal. A single-gland adenoma is responsible for 80% of PHPT cases. Less frequent causes include 4-gland hyperplasia and parathyroid carcinoma. Diminished bone mineral density and nephrolithiasis are the major current clinical sequelae. Parathyroidectomy is the only definitive treatment for PHPT, and in experienced hands, cure rates approach 98%.

Benign and Malignant Thyroid Gland Diseases in the Patients with Primary Hyperparathyroidism

Introduction:

This study aimed to evaluate concurrently detected thyroid pathologies in the patients who underwent surgery for primary hyperparathyroidism (PHPT).

Materials and Methods:

In this study, we retrospectively analyzed the files of the patients who underwent surgery for PHPT between 2012 and 2015. Pre- and post-operative laboratory examination results and preoperative radiological and nuclear medicine findings of the patients were retrospectively recorded.

Results:

A total number of 41 patients with PHPT were divided into two groups as the Group 1 with PHPT and benign thyroid pathology (21 patients) and the Group 2 with PHPT and malignant thyroid pathology (20 patients). In Group 1, 18 and 3 of 21 patients were females and males, respectively. Group 2 included 15 male and 5 female patients. The mean age of the patients was found to be 55.6 and 53.9 years in Group 1 and Group 2, respectively. Both groups were matched for age and gender. In terms of thyroid pathology, 20 of 41 patients (48.7%) who underwent total thyroidectomy for PHPT were found to have thyroid papillary carcinoma while benign pathologic conditions were detected in 21 (51.3%) individuals.

Conclusions:

Cooccurrence of thyroid diseases and PHPT is common. Therefore, all the patients should preoperatively be evaluated for the presence of thyroid pathology to determine the technique of parathyroid surgery.

Graves' Disease, Hypoparathyroidism, Systemic Lupus Erythematosus, Alopecia, and Angioedema: Autoimmune Polyglandular Syndrome Variant or Coincidence?

Data on coexisting Graves' disease (GD), hypoparathyroidism, and systemic lupus erythematosus (SLE) are limited. The thyroid and parathyroid glands may be extra sensitive to irradiation damage in an underlying autoimmune condition. A 34-year-old black woman presented with tetanic-like cramps, easy skin bruising, fatigue, weight gain, nocturia and back pain. She was previously diagnosed with GD in 2001 and underwent radioiodine therapy (RAI) in 9/01 using 6 mCi. PostRAI (November 2001) she developed hypocalcemia and hypothyroidism (2/02). In 2007, SLE was diagnosed. In October 2009, s-calcium and PTH were still low at 7.1 mg/dl and 9 pg/mL, respectively, although the patient denied symptoms on vitamin D and calcium supplementation. To identify possible autoimmune damage of the parathyroids, we evaluated the presence of activating antibodies to the CaSR and also analyzed the DNA sequence of all 6 translated exons and flanking intronic sequences of her CaSR gene for a functionally significant CaSR mutation but neither was positive. The initial autoimmune damage to her thyroid and possibly parathyroid glands followed by irradiation of them seems to have contributed to her developing both hypoparathyroidism (11/01) and hypothyroidism (2002). The patient could potentially have had parathyroid autoantibodies in 2001 that disappeared by 2009 when she was tested for them. We consider that the multiple autoimmune conditions developed over the past decade of her life with the concurrent irradiation contributing to her brittle hypoparathyroidism. Select patients with GD and perhaps parathyroid autoantibodies with a slowly developing destructive impact on the parathyroid glands may then develop overt hyoparathyroidism with rather low dose RAI ablation. This patient adds to the evolving spectrum of polyglandular syndrome variants.

Coexistence of parathyroid adenoma and papillary thyroid carcinoma

Purpose

Although several reports have been published regarding the coexistence of hyperparathyroidism and papillary thyroid carcinomas, concurrence of parathyroid adenoma and papillary thyroid carcinoma is extremely rare. The aim of this study was to describe experiences with concurrent parathyroid adenoma and papillary thyroid carcinoma.

Methods

Seven patients with concurrent parathyroid adenoma and papillary thyroid carcinoma were identified between January 2006 and December 2007, and their medical records were reviewed retrospectively.

Results

Of the seven patients identified, three were male and four were female; their mean age was 53.6 years. None of the patients presented with symptomatic hyperparathyroidism preoperatively. On laboratory findings, four patients had mild to moderate hypercalcemia, but serum parathyroid hormone concentrations were high in all patients. Preoperative imaging showed suspicious features of diseased parathyroid glands in four patients; two upon ultrasonography and computed tomography together and two upon ultrasonography only. The coexistence of parathyroid adenoma did not affect the extent of thyroid surgery. Laboratory values after surgery returned to within normal ranges in all patients.

Conclusion

It is important not only to analyze serum calcium levels but also to carefully interpret imaging studies in order to identify asymptomatic hyperparathyroidism when performing thyroid cancer surgery.

Primary hyperparathyroidism: an overview

Primary hyperparathyroidism is a common condition that affects 0.3% of the general population. Primary and tertiary care specialists can encounter patients with primary hyperparathyroidism, and prompt recognition and treatment can greatly reduce morbidity and mortality from this disease. In this paper we will review the basic physiology of calcium homeostasis and then consider genetic associations as well as common etiologies and presentations of primary hyperparathyroidism. We will consider emerging trends in detection and measurement of parathyroid hormone as well as available imaging modalities for the parathyroid glands. Surgical indications and approach will be reviewed as well as medical management of primary hyperparathyroidism with bisphosphonates and calcimimetics.

Bilateral neck exploration in primary hyperparathyroidism--when is it selected and how is it performed?

BACKGROUND

Although most patients with primary hyperparathyroidism (PHPT) are ideal candidates for minimally invasive parathyroidectomy, some will have more than one enlarged gland and require bilateral neck exploration to achieve biochemical cure. We evaluated the clinical evidence for when to choose bilateral neck exploration for patients with PHPT.

METHODS

We searched PubMed for English-language studies published from 1996 to 2008. The level of clinical evidence was determined according to the criteria proposed by Sackett (Chest 95[2 Suppl]:2S, 1989), and the grade of recommendation was established according to the criteria proposed by Heinrich et al. (Ann Surg 243:154, 2006).

RESULTS

Level III-IV evidence shows that patients with multiple endocrine neoplasia (MEN) 1 and PHPT should have a bilateral neck exploration (grade C recommendation). Only level IV evidence indicates that patients with familial PHPT should do so (no recommendation). Although most patients with MEN 2A have single-gland disease, bilateral neck exploration is still indicated, because they will have either a therapeutic or prophylactic total thyroidectomy for medullary thyroid cancer. A history of head and neck irradiation is associated with PHPT, but the risk of multi-gland parathyroid disease is apparently no higher than in sporadic cases (level IV evidence, no recommendation). Previous or current lithium therapy confers a higher risk of multi-gland disease (25%-45%; level IV-V evidence), which may require bilateral neck exploration. Preoperative localizing studies reliably identify most patients with single-gland but not multi-gland disease (level II-IV evidence). Negative localizing studies confer an approximately 50% risk of multi-gland disease and indicate that bilateral neck exploration is necessary. If two localizing studies are concordant, few patients will require bilateral neck exploration (level IV, no recommendation).

CONCLUSIONS

No level I or II evidence reliably identifies preoperative clinical risk factors for determining which patients should have routine bilateral neck exploration for multi-gland disease or for intraoperative decision making to convert to bilateral neck exploration. Imaging studies are positive in most patients (level II). No randomized studies exist to determine when a bilateral neck exploration is indicated based on clinical risk factors or imaging studies that may suggest multi-gland disease.

Prior head and neck radiation exposure is not a contraindication to minimally invasive parathyroidectomy

BACKGROUND

Most patients with primary hyperparathyroidism can have a minimally invasive parathyroidectomy based on localization studies showing single-gland disease. In patients with a history of head and neck irradiation, due to the increased risk of multigland disease and risk of concurrent thyroid cancer, minimally invasive parathyroidectomy is considered by some to be a contraindication. We postulated that previous history of head and neck irradiation should not be a contraindication for minimally invasive parathyroidectomy and tested this hypothesis in a prospective cohort of patients undergoing parathyroidectomy for primary hyperparathyroidism.

STUDY DESIGN

We performed a retrospective analysis of a prospective database of 491 consecutive parathyroidectomies performed between May 2005 and May 2007 at a tertiary referral medical center.

RESULTS

Fifty-two (12.6%) patients had a history of head and neck irradiation and 360 (87.4%) had no exposure to radiation. The 2 groups had no significant difference in terms of gender or ethnicity. The radiation group was older, with an average age of 65.1 years versus 58.1 years (p < 0.0009). There was no significant difference in concurrent benign thyroid neoplasm, thyroid cancer, and type of parathyroid disease (single vs multigland) in the 2 groups. There was no significant difference in the operative approach used between the 2 groups (focused vs unilateral or bilateral).

CONCLUSIONS

Head and neck irradiation should not be a contraindication for minimally invasive parathyroidectomy in patients with primary hyperparathyroidism in the setting of preoperative localization studies showing single-gland disease and no concurrent thyroid neoplasm. Furthermore, history of head and neck irradiation is associated with a later age of presentation for parathyroidectomy.

Parathyroid adenomas seen in the clinical follow-up of patients with differentiated thyroid carcinoma: a diagnostic dilemma

The coexistence of nonmedullary thyroid carcinoma and parathyroid adenoma is an uncommon clinical entity. In most of the previously published studies, thyroid carcinomas are diagnosed incidentally during or after the treatment of parathyroid disease, mostly in the pathology specimens. Here, we report 2 cases of parathyroid adenoma who presented years after the treatment of differentiated thyroid carcinoma. Neither of the patients had symptoms of hypercalcemia and hyperparathyroidism, and parathyroid adenomas were diagnosed on routine physical examination of the neck and on routine monitoring of serum calcium levels.

Endocrine sequelae of cancer and cancer treatments

INTRODUCTION

Exposure to cancer and its treatments, including chemotherapy and radiotherapy, may result in late adverse effects including endocrine dysfunction. Endocrine disorders are the most commonly reported long-term complications of cancer treatment, especially by adult survivors of childhood cancers. This review will explore the endocrinologic adverse effects from non-endocrine cancer therapies.

METHODS

Searches including various Internet-based medical search engines such as PubMed, Medline Plus, and Google Scholar were conducted for published articles.

RESULTS

One hundred sixty-nine journal articles met the inclusion criteria. They included case reports, systematic analyses, and cohort reports. Endocrine disorders including hypothalamus dysfunction, hypopituitarism, syndrome of inappropriate anti-diuretic hormone secretion, diabetes insipidus, growth hormone disorders, hyperprolactinemia, gonadotropin deficiency, serum thyroid hormone-binding protein abnormalities, hypothyroidism, hyperthyroidism, hypomagnesium, hypocalcemia, hyperparathyroidism, hyperparathyroidism, adrenal dysfunction, gonadal dysfunction, hypertriglyceridemia, hypercholesterolemia, diabetes mellitus, and glycosuria were identified and their association with cancer therapies were outlined.

DISCUSSION/CONCLUSIONS

The journal articles have highlighted the association of cancer therapies, including chemotherapy and radiotherapy, with endocrine dysfunction. Some of the dysfunctions were more often experienced than others. Especially in patients treated with radiotherapy, some endocrinologic disorders were progressive in nature.

IMPLICATIONS FOR CANCER SURVIVORS

Recognition and awareness of endocrine sequelae of cancer treatments may permit for early detection and appropriate follow-up care for cancer survivors, thus improving their overall health and quality of life.

[Hyperparathyroidism, goiter and well-differentiated thyroid carcinoma. A common association with diagnostic implications]

OBJECTIVE

To analyze thyroid gland disease incidentally found in patients undergoing surgery for hyperparathyroidism and to compare the frequency of nonmedullary thyroid carcinoma among different hyperparathyroidism varieties.

PATIENTS AND METHOD

We retrospectively reviewed 124 clinical records of patients who underwent surgery for hyperparathyroidism by a single surgeon from January 1998 to June 2006.

RESULTS

There were 105 women (84.7%) and 19 men (15.3%). The mean age was 59.7 +/- 15.66 years old. Of these, 115 (92.7%) were diagnosed with primary hyperparathyroidism and 9 (7.3%) with renal hyperparathyroidism. In the primary hyperparathyroidism group, 3 patients (2.6%) had received neck irradiation compared with none in the renal hyperparathyroidism group. Thyroid gland surgery was performed simultaneously in 43 patients (34.7%), 40 (34.8%) of them belonging to the first group and three (33.3%) to the second group (p = 1.00). Among the 115 patients operated on for primary hyperparathyroidism, 6 papillary thyroid carcinomas (5.2%) were found and 2 (22.2%) were found among the 9 patients with renal hyperparathyroidism, but this difference was not statistically significant (p = 0.105).

CONCLUSIONS

An incidental finding of thyroid disease in patients undergoing surgery for hyperparathyroidism is fairly frequent but no more so than that found in autopsy series. No statistically significant differences were found between primary and renal hyperparathyroidism in the prevalence of papillary thyroid carcinoma. Currently, neck irradiation does not seem to be a clinically significant factor in this issue. The high prevalence of thyroid disease in the general population warrants systematic neck ultrasound before hyperparathyroidism surgery.

Normal long-term parathyroid function after autologous bone marrow transplantation in children

Parathyroid function was recently reported to be affected in more than one-third of pediatric BMT patients conditioned without irradiation. Our aim was to describe parathyroid function in children with malignant hematological disease after autologous BMT with and without TBI. PTH, albumin-corrected serum calcium, and serum phosphate were analyzed in 35 children followed for six months to nine yr after BMT. Twelve patients were conditioned with chemotherapy alone, and 23 patients received TBI as well. In the TBI group, 11 patients had previously received additional CRT. We found normal levels of PTH in children post-BMT, with the exception of four patients (11%) who showed transient PTH elevation during the first year of follow-up, There was no difference between those who had received irradiation and those who had not. Serum calcium was unchanged after BMT. An age-corrected quotient of serum phosphate decreased slightly. Renal function which was normal before BMT decreased slightly in both groups after BMT, but was within the normal range. Parathyroid function was found to be normal during the time frame of this study, irrespective of whether irradiation had been given.

The impact of office neck ultrasonography on reducing unnecessary thyroid surgery in patients undergoing parathyroidectomy

BACKGROUND

Some have suggested that thyroid disease is even more prevalent among patients with hyperparathyroidism (HPT) than in the general population. We sought to define the incidence and optimal management strategies of thyroid disease in patients undergoing surgery for HPT.

METHODS

Clinical characteristics were reviewed for 1200 consecutive HPT patients treated at two endocrine surgery referral centers from 1992-2003. Both centers practice bilateral neck exploration, and one routinely obtains preoperative neck ultrasound (US) performed by surgeons.

RESULTS

Forty percent (477/1195) of HPT patients had coexisting thyroid disease, whether identified at parathyroidectomy (39%; 327/845) or by US (43%; 150/350). Colloid nodules/goiters accounted for nearly half of thyroid pathology, followed by follicular adenomas, papillary cancer, thyroiditis, and intrathyroidal parathyroids. Thyroid malignancy was found in 4.6% of HPT patients versus less than 1% in autopsy reports. Thyroid pathology was similar among single adenomas, multigland, and renal HPT. Unexpected thyroid disease first encountered at parathyroidectomy required partial or total thyroidectomy in 30% (257/845). US-detected thyroid nodules prompted fine-needle biopsy in 20%, which was cost effective in limiting concomitant thyroid surgery to fewer patients (6%; 21/350). Overall low incidence (<0.5%) of persistent/recurrent HPT, nerve injury, and neck hematoma was unaffected by thyroid abnormalities.

CONCLUSIONS

The high prevalence of thyroid disease, especially malignancies, among HPT patients mandates vigilant diagnosis and preparation for possible simultaneous parathyroid-thyroid surgery. Without appropriate preoperative screening, focal explorations for HPT may be prone to delayed diagnosis of thyroid tumors. Ultrasound performed by surgeons or endocrinologists preoperatively is an excellent diagnostic tool and minimizes unnecessary thyroidectomy in patients with subclinical thyroid disease.