Incidentally discovered parathyroid lipoadenoma in thyroid surgery: A case report and review of the literature.

Parathyroid lipoadenoma is a rare type of parathyroid adenoma, described as a single parathyroid adenoma with more than 50% fat on histologic examination and an unknown etiology, which is one of the rare causes of primary hyperparathyroidism. The difficulty of parathyroid lipoadenoma is mainly diagnosed by preoperative imaging localization. We hope to arouse attention to the parathyroid adenoma which is difficult to locate through our case report. The patient was a middle-aged male with a body mass index of 38.4 kg/m2 who admitted to our hospital with a 40-day history of an untreated thyroid nodule. We incidentally discovered parathyroid lipoadenoma in his thyroid surgery. His prognosis was good, and there were no signs of recurrence at his 12-month follow-up appointment. We believe that parathyroid lipoadenoma needs to rely on paraffin pathology to make a final diagnosis. This case report serves as a reminder that parathyroid lipoadenomas are also possible in patients who do not have primary hyperparathyroidism preoperatively and who have negative imaging. Clinicians must carefully examine the adipose tissue for the presence of parathyroid lipoadenomas during thyroid surgery to avoid postoperative hypoparathyroidism and persistent hypocalcaemia.

A Rare Case of Recurrent Parathyroid Adenomas After Initial Parathyroidectomy.

Hyperparathyroidism usually presents asymptomatically with elevated levels of calcium and parathyroid hormone; this biochemical imbalance establishes the diagnosis. In 80-85% of cases of primary hyperparathyroidism, singular parathyroid adenomas occur. In rare cases, this problem occurs due to multiple adenomas, multiglandular hyperplasia, or parathyroid carcinoma. Recurrent primary hyperparathyroidism (R-PHPT), as demonstrated in this case, is defined as hypercalcemia that arises after six months of normocalcemia following initial surgery for PHPT. The aim of this report is to describe the diagnosis and management of three parathyroid adenomas in a patient, two of which occurred after an initial partial parathyroidectomy.

Large Water-Clear-Cell Parathyroid Adenoma: A Report of a Rare Case.

Water-clear-cell parathyroid adenomas are extremely rare tumors characterized by cells that contain clear, foamy cytoplasm. Here we report a case of a large water-clear-cell parathyroid adenoma in a 70-year-old male. The patient was presented to an outside hospital with severe abdominal pain and supporting CT imaging confirming a small bowel obstruction. Initial laboratory studies revealed hypercalcemia and elevated parathyroid hormone levels. Subsequent ultrasound imaging revealed a 2.7 × 2.1 cm neck mass suspicious for a parathyroid adenoma. A parathyroidectomy was performed, and microscopic evaluation revealed an expansile proliferation of cells with characteristic water-clear cell features. Although rare, water-clear-cell parathyroid adenomas are clinically indistinguishable from more common subtypes and should be considered in the differential diagnosis of an anterior neck mass.

Hipercalcemia asociada a hiperparatiroidismo primario: enfoque y manejo a partir de un caso clínico

Introducción: el calcio es el electrolito más abundante del cuerpo humano y la hipercalcemia es el trastorno común causado normalmente por el hiperparatiroidismo primario o malignidad, su manejo depende de la presentación y causa subyacente. Además, una proporción de casos se presentan como una emergencia, lo que conlleva a una mortalidad significativa. Objetivo: mostrar un caso inusual de presentación clínica de hipercalcemia asociada a hiperparatiroidismo primario y, asimismo, dar una breve revisión acerca del enfoque y el manejo de esta patología. Presentación del caso: paciente femenina de 32 años, antecedente de adenoma paratiroideo no resecado y pancreatitis, asiste por tres días de dolor abdominal de tipo cólico y de moderada intensidad, acompañado de episodios eméticos de contenido alimentario, paraclínicos iniciales con hipercalcemia severa, electrocardiograma con bloqueo auriculoventricular grado I, gases arteriales con alcalosis respiratoria aguda e hiperlactatemia. También se le practicó un TAC de abdomen donde este apareció con tumores pardos. Se ingresó a la UCI para la administración de líquidos endovenosos, diuréticos de asa y cinacalcet, pero no presentó mejoría, por lo que se indicó terapia de hemodiálisis. Discusión y conclusión: la hipercalcemia es un hallazgo frecuente. El hiperparatiroidismo primario y la neoplasia maligna son las dos causas más frecuentes de aumento de los niveles de calcio sérico y, en conjunto, representan alrededor del 90 % de todos los casos, donde los valores en suero varían entre el calcio total (8,5 y 10,5 mg/dl) y el iónico (1,16-1,31). La concentración sérica de Ca 2+ está estrechamente relacionada por las acciones de la hormona paratiroidea y el calcitriol, donde el hiperparatiroidismo primario ocurre como resultado de adenomas, hiperplasias y carcinoma. Las manifestaciones clínicas y la severidad van a estar correlacionadas con el tiempo de duración de la enfermedad, los niveles de calcio y de PTH. Dentro del tratamiento, este será guiado por su causa, sin embargo, es posible clasificarlo en tratamiento urgente y no urgente. Además, el enfoque de la hipercalcemia aguda severa es un reto diagnóstico dadas las múltiples causas que pueden llevar a este trastorno hidroelectrolítico y la rápida instauración de tratamiento que se requiere cuando es detectada.

Background: Calcium is the most abundant electrolyte in the human body, hypercalcemia is a common disorder usually caused by primary hyperparathyroidism or malignancy. A proportion of cases presenting as an emergency, leading to significant mortality. The management of hypercalcemia depends on the presentation and underlying cause. Purpose: to present an unusual case of clinical presentation of hypercalcemia associated with primary hyperparathyroidism, as well as to give a brief review about the approach and management of this pathology. Case presentation: A 32-year-old female patient, with a history of unresected parathyroid adenoma and pancreatitis, attended for 3 days of abdominal pain, moderate intensity, accompanied by emetic episodes of food content, initial paraclinical findings showed severe hypercalcemia, electrocardiogram with block grade I atrioventricular, arterial gases with acute respiratory alkalosis and hyperlactatemia. CT of the abdomen with brown tumors. She was admitted to the ICU for administration of intravenous fluids, loop diuretics, and cinacalcet without showing any improvement, so hemodialysis therapy was indicated. Discussion and conclusion: hypercalcemia is a frequent finding. Primary hyperparathyroidism and malignancy are the two most common causes of elevated serum calcium levels, together accounting for about 90 % of all cases. Serum values vary between total calcium 8.5 and 10.5 mg/dl and ionic 1.16- 1.31. Serum Ca 2+ concentration is closely related by the actions of parathyroid hormone and calcitriol. Primary hyperparathyroidism occurs as a result of adenomas, hyperplasias, or carcinoma. The clinical manifestations and severity will be correlated with the duration of the disease, calcium and PTH levels. Within the treatment, this will be guided by its cause, however, it is possible to classify it into urgent and non-urgent treatment. The approach to severe acute hypercalcemia is a diagnostic challenge given the multiple causes that can lead to this hydroelectrolyte disorder and the rapid establishment of treatment that is required when it is detected.

Parathyroid fine-needle aspiration with parathyroid hormone washout as a preoperative localisation of parathyroid adenoma-A retrospective study.

OBJECTIVE: The use of parathyroid lesion aspiration in preoperative adenoma localisation is controversial. Concerns have been raised regarding both immediate safety (hematoma, infection, alterations on a subsequent histologic preparate) and long-term safety (seeding). We aimed to evaluate the short- and long-term safety, and the efficacy, of parathyroid fine-needle aspiration with parathyroid hormone washout as a localisation modality of parathyroid adenoma in patients with primary hyperparathyroidism. DESIGN: A retrospective study. PATIENTS: The sample comprised 29 patients with primary hyperparathyroidism who underwent minimally invasive parathyroidectomy at a tertiary referral centre, following localisation with parathyroid hormone washout. MEASUREMENTS: We reviewed all parathyroid hormone washout procedures performed during 2011-2021. Clinical, biochemical, and imaging information; and cytology, surgery, and pathology reports were extracted from electronic medical records. RESULTS: Parathyroid hormone levels from the needle wash were 2.1-112.5 times the upper limit of the serum norm. Other than mild neck discomfort, no immediate procedure complications were documented. Fibrotic changes and necrosis were reported in two patients, with no effect on the final pathologic diagnosis or surgery course. No long-term complications (seeding, or parathyromatosis) were found. A total of 26 (90%) patients who were operated following a positive parathyroid hormone washout result were normocalcemic at the end of a mean 38.1-month follow-up period. CONCLUSIONS: Parathyroid fine-needle aspiration with parathyroid hormone washout was accurate. Immediate, surgical, or delayed complications were not demonstrated in our series. This approach might be considered for selected patients.

Ectopic parathyroid adenoma in a patient with multiple endocrine tumours.

Not required for Clinical Vignette.

Revision parathyroid surgery - challenges and considerations in comparison to primary surgery.

OBJECTIVE: Revision parathyroidectomy is made necessary by recurrent or persistent parathyroid disease. This study aimed to identify challenges in revision surgery compared to primary parathyroid surgery. METHODS: All revision parathyroidectomies performed by one surgeon over a 17-year period were assessed for demographics, imaging, histology, biochemistry, cure rate, gland weight, gland location and gland ectopia, and compared to a series of 100 primary parathyroidectomies. RESULTS: Twenty-eight revision surgical procedures were identified. Sestamibi scanning for gland localisation was superior to ultrasound in both primary and revision surgery. Pre-operative calcium and gland weight were significantly higher in revision cases. There were no significant differences in post-operative calcium levels, pre- or post-operative parathyroid hormone levels, or gland location. 36 per cent of glands excised in revision surgery were ectopic, compared to 25 per cent in primary procedures. The cure rate was significantly lower in revision surgery. CONCLUSION: Revision parathyroidectomy patients present with higher pre-operative calcium and larger adenomas; the cure rate is significantly lower in these patients.

A Nomogram for Relapse/Death and Contemplating Adjuvant Therapy for Parathyroid Carcinoma.

Parathyroid carcinoma (PC) is a rare endocrine malignancy with an increased incidence in the last decade. There is no reliable prognostic staging system for PC. Several hosts, tumors, and tumor microenvironment factors have been negatively correlated with survival in the last decade. Surgical resection with negative margins is still the standard of treatment in PC. Chemo and radiotherapy have no proven beneficial effect. A new promising approach with molecular profiling could lead to adjuvant therapies.

A Silent Non-thyroidal Adenoma in the Thyroid.

The surgeon needs to assess clinically significant thyroid nodules as they may represent aggressive forms of thyroid cancer or ectopic parathyroid glands. We discuss one such unusual nodule in the thyroid.

Application value of contrast-enhanced ultrasound in preoperative localization of microwave ablation for primary hyperparathyroidism.

BACKGROUND: Ultrasonography (US) and 99m Technetium-sestamibi scintigraphy (99m Tc-MIBI) are currently first-line imaging modalities to localize parathyroid adenomas with sensitivities of 80% and 84%, respectively. Therefore, finding other modalities to further improve the diagnostic accuracy for preoperative localization is critically needed. PURPOSE: To evaluate the application value of contrast-enhanced ultrasound (CEUS) in the preoperative localization of microwave ablation (MWA) for primary hyperparathyroidism (PHPT). METHODS: Between December 2012 and May 2021, 100 PHPT patients (34 males and 66 females; mean age, 56.31 ± 13.43 years; age range, 25-85 years) with 130 suspected parathyroid nodules were enrolled. US, CEUS, and 99m Tc-MIBI were performed for the localization of pathological parathyroid glands. All patients were performed MWA under ultrasound guidance. All the suspected parathyroid nodules underwent core needle biopsy under ultrasound guidance during MWA to confirm the pathology. The diagnostic performance of all the imaging tests was analyzed in comparison with the pathological results. RESULTS: A total of 130 nodules suspected to be of parathyroid origin from preoperative localization images were confirmed by pathological results, of which 116 were of parathyroid origin, and 14 were not of parathyroid origin. The sensitivity, specificity, accuracy, and the area under receiver operating characteristic curve of CEUS in the localization of pathological parathyroid glands were 100%, 92.86%, 99.23%, and 0.964, which were significantly higher than those of US (93.10%, 42.86%, 87.69%, and 0.680) and 99m Tc-MIBI (81.90%, 42.86%, 77.69%, and 0.624) (p < 0.05). The sensitivity and accuracy of CEUS were 100% and 97.22%, which were higher than those of 99m Tc-MIBI (65.62% and 63.89%) or US (75.00% and 72.22%) in patients with multiple parathyroid glands (p < 0.05). For smaller parathyroid adenomas (≤2 cm in diameter), the sensitivities of CEUS in locating hyperfunctioning parathyroid glands were 100%, which was significantly higher than that of 99m Tc-MIBI (73.68% and 84.31%, p < 0.05). CONCLUSIONS: CEUS is a valuable preoperative localization method for PHPT patients performed MWA, especially for the patients with smaller pathological parathyroid gland and multiple glandular lesions.

Retropharyngeal Ectopic Parathyroid Adenoma Localized by 18F-Fluorocholine Positron Emission Tomography/Computed Tomography: A Case Report.

Ectopic parathyroid adenomas of the retropharyngeal space are relatively rare. Herein, we report a case of primary hyperparathyroidism (PHPT) secondary to a retropharyngeal parathyroid adenoma. A 22-year-old woman presented with elevated serum calcium and parathyroid hormone (PTH) levels, revealed during a medical check-up. The patient had a history of ureteral stones and a confirmed low bone mass. Neck 99mTechnetium-sestamibi singlephoton emission computed tomography (CT) and ultrasonography did not reveal any suspicious lesions. There was no evidence of hereditary PHPT based on the results of targeted gene sequencing. Surgical exploration was unsuccessful, and the PHPT persisted after the first surgery. Approximately a year after the failed operation, 18F-fluorocholine (FCH) positron emission tomography/CT (PET-CT) became available, and when performed, it revealed increased uptake in the retropharyngeal space of the right side of the neck. The results of parathyroid venous sampling were concordant with a >2-fold elevation of PTH level in the veins on the right side of the neck compared to the peripheral veins. The 1.8 cm-diameter mass was successfully removed resulting in an 87% reduction in intraoperative PTH level (198.0-26.5 pg/mL). Subsequently, normalizations of calcium and PTH levels were achieved. In summary, ectopic parathyroid adenomas, including retropharyngeal lesions, should also be suspected when investigating an elusive case of PHPT. 18F-FCH PET-CT can be a useful complementary modality for detecting culprit lesions.

Parathyroid Carcinoma: a Review.

Parathyroid cancer is a rare endocrine malignancy with only a few thousand cases reported worldwide. As a result, there exists considerable controversy regarding the various aspects of this disease, viz., etiology, diagnosis, and management. We hereby attempt to review the literature on parathyroid carcinoma (PC) and summarize the practices based on the current evidence available. The majority of the PC are sporadic although an association with hyperparathyroidism-jaw tumor syndrome, multiple endocrine neoplasia (MEN) 1 and 2, and isolated familial hyperparathyroidism has been shown. As preoperative diagnosis is challenging, PC should be suspected in patients presenting with a neck mass with signs and symptoms of invasion to surrounding structures. Skeletal and renal symptoms are often associated with PC as presenting complaints. The biochemical parameters are more pronounced in the case of PC compared with benign countpart. Due to its rarity, the American Joint Committee of cancer control (AJCC) acknowledges that as yet a clear distinct staging system to prognosticate the disease would be premature. Complete excision with negative margins at first surgery offers the best chance of cure. The role of radiotherapy (RT) is still unclear; however few series have suggested a better locoregional control with adjuvant RT. Recurrences are common and are most significantly associated with an incomplete clearance at initial surgery. Surgical salvage of recurrent/metastatic disease with medical management of hypercalcemia is the treatment of choice. Large prospective studies and trials need to be conducted to understand the pathology better and improve management protocols; however this is a challenge due to rarity of cases.

A visual deep learning model to predict abnormal versus normal parathyroid glands using intraoperative autofluorescence signals.

BACKGROUND: Previous work demonstrated that abnormal versus normal parathyroid glands (PGs) exhibit different patterns of autofluorescence, with former appearing darker and more heterogenous. Our objective was to develop a visual artificial intelligence model using intraoperative autofluorescence signals to predict whether a PG is abnormal (hypersecreting and/or hypercellular) or normal before excision during surgical exploration for primary hyperparathyroidism. METHODS: A total of 906 intraoperative parathyroid autofluorescence images of 303 patients undergoing parathyroidectomy/thyroidectomy were used to develop model. Autofluorescence image of each PG was uploaded into the visual artificial intelligence platform as abnormal or normal. For deep learning, randomly chosen 80% of data was used for training, 10% for testing, 10% for validation. The area under the receiver operating characteristic (AUROC), area under the precision-recall curve (AUPRC), recall (sensitivity), and precision (positive predictive value) of the model were calculated. RESULTS: AUROC and AUPRC of the model to predict normal and abnormal PGs were 0.90 and 0.93, respectively. Recall and precision of the model were 89% each. CONCLUSION: Visual artificial intelligence platforms may be used to compare the autofluorescence signal of a given parathyroid gland against a large database. This may be a new adjunctive tool for intraoperative assessment of parathyroid glands during surgical exploration for primary hyperparathyroidism.

Fluorine-18 Fluorocholine Positron Emission Tomography/Computed Tomography in Primary Hyperparathyroidism: A Case Report and Review of Literature.

Positron emission tomography (PET) tracers (Fluorine-18 Fluorocholine [18F-Fluorocholine] and Carbon-11 Choline [11C-Choline]) have been widely used with promising accuracy in detecting abnormal parathyroids, being crucial for an effective and safe minimally invasive parathyroidectomy. We report a case of a 72-year-old woman with a long-term personal history of osteoporosis and recurrent nephrolithiasis with the need for invasive interventions. Primary hyperparathyroidism was biochemically assumed, although localization of the hyperfunctioning parathyroid had been challenging since cervical ultrasound and technetium-99m sestamibi scintigraphy were negative/equivocal. An 18F-Fluorocholine positron emission tomography/computed tomography (PET/CT) was performed, having identified a small cervical nodule with increased tracer uptake, compatible with a right parathyroid adenoma. After its removal, the patient went into clinical and biochemical remission. 18F-Fluorocholine PET/CT allowed an effective and safe parathyroidectomy as conventional imaging modalities were inaccurate in detecting the abnormal parathyroid, in this patient with serious hyperparathyroidism-related complications.

Parathyroid carcinoma: Single centre experience.

OBJECTIVE: Parathyroid Carcinoma is a rare malignant neoplasm, accounting for less than 1% of primary hyperparathyroidism cases. Parathyroid carcinomas are characterized by markedly elevated levels of PTH, severe hypercalcemia and established target organ damage. The authors report the experience of a single centre regarding the management and outcome of patients with parathyroid carcinomas and revise relevant literature. DESIGN: Retrospective review of all patients with parathyroid carcinoma evaluated at a tertiary oncologic centre from 1991 until 2021. RESULTS: Seventeen patients were identified (10 males), with a mean age at diagnosis of 53 ± 16 years and a median follow-up of 16.5 years. Most patients presented with hypercalcemia (n = 15), with a mean serum calcium concentration of 13.5 mg/dl (9.6-16.5) and mean PTH of 1173 pg/ml (276-2500). Hyperparathyroidism-mediated organ damage was observed in most patients (n = 16), with predominant renal (n = 12) and skeletal (n = 9) complications. En bloc surgical resection was performed in nine patients. Three patients underwent adjuvant radiotherapy. Recurrence was observed in 8 cases (47.1%) after a median of 24 months following surgery and no independent predictors of recurrence were identified. The overall survival and disease specific survival at 5-year was 88% and 94%, respectively. CDC73 mutations were present in 38.5% of analysed patients and one patient was diagnosed with MEN1. CONCLUSION: Parathyroid carcinoma is associated with a significant rate of recurrence and limited effective treatment beyond initial complete surgical resection. Therefore, preoperatively high index of suspicion is paramount to optimize patient care. This is, to our knowledge, the largest Portuguese cohort published so far.

Giant parathyroid tumours in primary hyperparathyroidism: a systematic review.

PURPOSE: Giant parathyroid adenoma (GPA) can present with severe biochemical derangement similar to the clinical presentation of parathyroid carcinoma (PC). This study aims to present the current evidence on surgical management of GPAs in primary hyperparathyroidism. METHODS: A systematic review of the literature on GPAs was conducted following the PRISMA guidelines. Data on clinical, biochemical, preoperative diagnostic, and surgical methods were analysed. RESULTS: Sixty-one eligible studies were included reporting on 65 GPAs in eutopic, ectopic mediastinal, and intrathyroidal locations (61.5%, 30.8%, and 7.7%, respectively). A palpable neck mass was present in 58% of GPAs. A total of 90% of patients had symptoms including fatigue, skeletal pain, pathological fracture, nausea, and abdominal pain. Ninety percent of patients had significant hypercalcaemia (mean 3.51 mmol/L; range: 2.59-5.74 mmol/L) and hyperparathyroidism with PTH levels on average 14 times above the upper limit of the normal reference. There was no correlation between the reported GPA size and PTH nor between GPA weight and PTH (p = 0.892 and p = 0.363, respectively). Twenty-four percent had a concurrent thyroidectomy for suspicious features, intrathyroidal location of GPA, or large goitre. Immunohistochemistry such as Ki-67, parafibromin, and galectin-3 was used in 18.5% of cases with equivocal histology. Ninety-five percent of GPAs were benign with 5% reported as atypical adenomas. CONCLUSION: The reported data on GPAs are sparse and heterogeneous. In GPAs with suspicious features for malignancy, en bloc resection with concurrent thyroidectomy may be considered. In the presence of equivocal histological features, ancillary immunohistochemistry is advocated to differentiate GPAs from atypical adenomas and PCs.

Challenging NICE guidelines on parathyroid surgery.

BACKGROUND: National Institute of Clinical Excellence (NICE) recommend against routinely using Intra-Operative Parathyroid Hormone (IOPTH) for first-time parathyroid surgery due to its cost and minimal surgical benefit. The European Society of Endocrine Surgeons differ from this and recommends IOPTH with conflicting pre-operative or single imaging. NICE guidance acknowledged that this may change practice in larger centres. We devised a retrospective single-centre cohort study to analyse the impact of IOPTH on decision-making and cost-effectiveness. METHODOLOGY: First-time parathyroidectomy procedures for primary hyperparathyroidism were assessed between 2017 and 2019. Ultrasound (US) and Sestamibi with parathyroid single-photon emission with computed tomography (SPECT-CT) were compared with IOPTH. The contribution of IOPTH to cure and cost effectiveness ratio was calculated. RESULTS: 114 cases were included, with IOPTH performed in all cases, SPECT-CT in 112 and US in 108 cases. A cure rate of 99.1% (113/114) was achieved. 11.4% (13/114) of the cure rate was influenced by IOPTH (P 0.01), instigating further exploration when its levels didn't decrease. This included 7.1% (4/56) in the concordant-imaging cohort. IOPTH accuracy (96.5%) was significantly superior (P = 0.03) to both US (80%) and SPECT-CT (81%). Comparing the total costs for IOPTH testing over 2 years (£39,721) with 13 potential re-operative procedures in its absence (£63,536), a positive cost-effectiveness ratio of £1832 per re-operative procedure averted was achieved. CONCLUSION: Abandoning IOPTH in first-time parathyroid surgery is too ambitious when weighing the cost of re-operative surgery against cost savings obtained by using routine IOPTH to achieve an improved cure rate, even in concordant imaging.

Ectopic pure mediastinal parathyroid adenoma: A case report.

INTRODUCTION AND IMPORTANCE: The ectopic parathyroid adenoma is an important cause of refractory and recurrent hyperparathyroidism. The mediastinal location of ectopic parathyroid tissue is reported in up to 20% of cases of ectopic parathyroid adenomas. In around 2% of cases where cervical approach is unfeasible, the mediastinal route imposes a surgical challenge. CASE PRESENTATION: We describe a case of a twenty-five-year-old male patient with manifestations of hyperparathyroidism. Computed tomography of the chest showed an anterior mediastinal mass. Nuclear scintigraphy detected a functioning parathyroid tissue in the mediastinum. The mass was excised en block with the surrounding adipose tissue using a three-port video-assisted thoracoscopic surgery. The patient showed a full symptomatic and laboratory recovery. CLINICAL DISCUSSION: Mediastinal parathyroid glands comprise a unique surgical entity with diagnostic and management difficulties. CONCLUSION: Mediastinal parathyroid gland is a rare yet important cause of refractory hypercalcemia. The current localization tools improve the thoracoscopic management of MPAs. VATS can provide access and exposure to ectopic parathyroid adenoma with low morbidity.

Spontaneous extracapsular parathyroid adenoma hemorrhage: when surgery is required?

PURPOSE: Spontaneous bleeding is a rare but serious complication of parathyroid adenomas and few cases were reported in the literature. Clinical manifestations and treatment may vary but sometimes an immediate surgery is required. In other cases a conservative approach can be preferred based on clinical stability and patients' conditions. The purpose of this work is to describe our case and to carry out a review of the current literature on this topic. METHODS: We reported a case of a parathyroid adenoma hemorrhage in an elderly patient describing its management. Moreover, a literature review of 57 cases was carried out, with the aim of collecting data about the most involved parathyroid gland and identifying the most correct management based on clinical manifestations and chosen treatments. RESULTS: The patients had an age between 29 and 81 years (mean 56.9 ± 16.4 years). Forty-four patients were females (77.2%), whereas 12 were males (21.8%). Based on clinical severity, age, comorbidities and calcemic status, three possible scenarios were identified, each with a recommended management. CONCLUSIONS: In parathyroid adenoma hemorrhages a careful clinical assessment is crucial to identify emergency conditions requiring immediate intubation, tracheostomy or neck exploration. Elderlies and comorbid patients have a higher risk of perioperative complications and indication for surgery should be evaluated case by case: whenever feasible, a conservative approach should be preferred in these subjects, especially in those with a stable course and without hypercalcemia-related symptoms.

The key to simplified management of an undescended parathyroid adenoma.

Undescended parathyroid adenoma is a rare cause of primary hyperparathyroidism that happens < 1% of cases. If not suspected, it can lead to a negative bilateral parathyroid exploration and extensive iatrogenic trauma. We propose that with proper imaging the correct diagnosis can be established to simplify surgical management. We describe two cases of patients who underwent a targeted neck exploration due to an undescended parathyroid adenoma diagnosed with an appropriate preoperative imaging protocol. With an appropriate imaging protocol for primary hyperparathyroidism and parathyroid hormone aspirates, an undescended parathyroid adenoma can be primarily diagnosed to guide a focused parathyroidectomy.

El adenoma paratiroideo no descendido ocasiona hiperparatiroidismo primario en <1% de los casos. Si no se sospecha, puede llevar a exploraciones negativas y trauma iatrogénico extenso. Proponemos que, con un protocolo imagenológico adecuado, se puede realizar un diagnóstico correcto, simplificando el abordaje quirúrgico. Describimos dos casos en que se realizó una exploración de cuello dirigida debido a un adenoma paratiroideo no descendido diagnosticado con un protocolo de imagen preoperatorio apropiado. Un protocolo de imagen apropiado para hiperparatiroidismo primario y aspirados de PTH pueden diagnosticar de manera inicial un adenoma paratiroideo no descendido para guiar una paratiroidectomía dirigida.