Risk Score of Neck Hematoma: How to Select Patients for Ambulatory Thyroid Surgery?

BACKGROUND: The risk of postoperative compressive hematoma is the major limitation for a wide development of ambulatory thyroidectomy (AT). The aim of this study was to establish a risk score of hematoma on the basis of preoperative criteria. METHODS: All patients who underwent thyroidectomy between 2002 and 2017 were reviewed in a high-volume endocrine surgery center. Multivariate analysis of risk factors associated with hematoma was performed in lobectomy and total thyroidectomy (TT). We assigned the risk factors identified by multivariate analysis weighted points proportional to the regression coefficient values. A simple sum of all accumulated points for each patient calculated the total score. RESULTS: For lobectomy [31 hematoma among 3912 patients (0.8%)], the weighted points of Vit K antagonist (VKA) were 3 (OR 9.86), and 1 in male gender (OR 2.4). For TT [162 hematoma among 13,903 patients (1.2%)], the weighted points of VKA were 4 (OR 12.18), 1 in male gender (OR 1.89), and 1 for diabetes (OR 1.86). Other factors weighted 0 in both groups. A total score >1 was linked to a risk of hematoma > 1.3% for lobectomy or TT. AT should not be proposed to any patient under VKA, and in case of TT, to male patients with diabetes. Prospectively, patients had AT from May 2018 to February 2020, 529 patients underwent ambulatory TL (483) or TT (46) and only one patient experienced neck hematoma. CONCLUSION: We established a simple and reproducible predictive score of early discharge for lobectomy and TT that could be useful for patients' management.

Management of the injured bowel: preserving bowel continuity as a gold standard.

BACKGROUND: Management of bowel traumatic injuries is a challenge. Although anastomotic or suture leak remains a feared complication, preserving bowel continuity is increasingly the preferred strategy. The aim of this study was to evaluate the outcomes of such a strategy. METHODS: All included patients underwent surgery for bowel traumatic injuries at a high volume trauma center between 2007 and 2017. Postoperative course was analyzed for abdominal complications, morbidity and mortality. RESULTS: Among 133 patients, 78% had small bowel injuries and 47% had colon injuries. 87% of small bowel injuries and 81% of colon injuries were treated with primary repair or anastomosis, with no difference in treatment according to injury site (p = 0.381). Mortality was 8%. Severe overall morbidity was 32%, and abdominal complications occurred in 32% of patients. Risk factors for severe overall morbidity were stoma creation (p = 0.036), heavy vascular expansion (p = 0.005) and a long delay before surgery (p = 0.023). Fistula rate was 2.2%; all leaks occurred after repairing small bowel wounds. CONCLUSION: Primary repair of bowel injuries should be the preferred option in trauma patient, regardless of the site-small bowel or colon-of the injury. Stoma creation is an important factor for postoperative morbidity, which should be weighed against the risk of an intestinal suture or anastomosis.

Risk of recurrence in a homogeneously managed pT3-differentiated thyroid carcinoma population.

BACKGROUND: International guidelines for the management of differentiated thyroid cancers are based on the 7th TNM classification: pT3 tumors are defined as differentiated thyroid cancers (DTCs) measuring more than 4 cm in their greatest dimension that are limited to the thyroid or any tumor with minimal extrathyroidal extension (ETE; sternothyroid muscle or perithyroid soft tissues). Differences in clinicohistological features and prognosis among patients with pT3 tumors remain controversial, and studies regarding pT3 subgroups are lacking. OBJECTIVE: To analyze the prognosis of four subgroups of pT3 DTCs (papillary, PTC; or follicular, FTC). DESIGN AND SETTING: The data of patients who underwent surgery for pT3 DTC between 1978 and 2015 in a surgical department specialized in endocrine surgery were reviewed. Patients were classified into four groups as follows: the pT3a (≤ 10 mm with ETE), pT3b (10-40 mm with ETE), pT3c (> 40 mm without ETE), and pT3d groups (> 40 mm with ETE). Recurrence-free survival (RFS) was analyzed using the Kaplan-Meier method. RESULTS: One thousand eighty-eight patients with pT3 DTC were included, of whom 311 (29%) had pT3a; 548 (50%), pT3b; 165 (15%), pT3c; and 64 (6%), pT3d. For the 916 patients with lymph node (LN) dissection, metastatic LNs were more frequent in the pT3b and pT3d groups (61 and 61%, respectively) than in the other groups (44% pT3a and 10% pT3c; p < 0.001). During the median follow-up period of 9 years (range, 2-38 years), recurrence occurred in 169 patients with T3 tumors (16%), including 18 with pT3a (6%), 100 with pT3b (18%), 20 with pT3c (12%), and 31 with pT3d (48%). In a multivariate analysis, LN metastases (< 0.0001), extranodal extension (p = 0.03), FTC (vs. PTC) (p = 0.006), pT3b (p = 0.016), and pT3d (p = 0.047) were associated with an increased risk of recurrence. The 5-year RFS rates were 94.5, 82.2, 91.1, and 50.3% for the pT3a, pT3b, pT3c, and pT3d groups, respectively (p < 0.01). CONCLUSION: Except for microcarcinoma, the risk of LN involvement is high and similar for the DTC patients with minimal ETE, regardless of the size of the tumor. The association of a tumor size of > 4 cm and ETE are associated with a poor prognosis and should justify the classification of these cases as a high-risk group. Other pT3 patients with no LN metastases could be individualized as a low-risk group.

Can We Predict the Lateral Compartment Lymph Node Involvement in RET-Negative Patients with Medullary Thyroid Carcinoma?

BACKGROUND: Lateral lymph node dissection (LND) in the absence of macroscopic nodal metastasis remains controversial in sporadic medullary thyroid carcinoma (MTC). OBJECTIVES: The aims of our study were to determine the risk of lateral lymph node (LN) metastases with a focus on lateral contralateral N1, and to define a risk-adapted surgical treatment for these patients. METHODS: All patients who underwent surgery from 1980 to 2012 for previously untreated RET-negative MTC were reviewed. We focused on the lateral compartments of LN metastases and identified three groups: no lateral LN metastases, ipsilateral lateral (ILL)-LN metastases with no contralateral LN involvement, and contralateral lateral (CLL)-LN metastases. RESULTS: Overall, 131 patients underwent surgery for RET-negative MTC. A total thyroidectomy with LND was performed in 112 patients (85 %), including 97 patients who had an ILL-LND and 92 patients who had a CLL-LND. Lateral LN metastases (N1) occurred in 40 patients (37 %): 31 patients (32 %) had ILL-LN metastases with no contralateral LN involvement, and 9 patients (10 %) had CLL-LN metastases. The preoperative cut-offs for LN metastases in the ILL compartment were very low, with a smallest tumor size of 5 mm, and lowest serum calcitonin level of 38 pg/ml. Disease-free survival rates decreased from 92 % for patients with no lateral LN metastases to 41 % for patients with ILL-LN metastases and 0 % for patients with CLL-LN metastases. CONCLUSIONS: ILL-LND should be performed in every patient and only a minority of MTC patients with small micro-MTC, and low serum calcitonin levels should not have a CLL-LND.

Does the T1 subdivision correlate with the risk of recurrence of papillary thyroid cancer?

BACKGROUND: Based on the AJCC seventh TNM classification, T1 intraglandular tumors are subdivided into T1a (≤10 mm) and T1b (11-20 mm), but the differences in prognosis remain controversial. The present study aimed to determine the clinicopathological features and outcomes of T1a and T1b patients. METHODS: A retrospective study of 2518 T1 patients, including 1840 T1a (73 %) and 678 (27 %) T1b patients who underwent surgery for PTC from 1978 to 2014, was conducted. In patients with a preoperative or operative diagnosis of PTC, a total thyroidectomy (TT) with prophylactic (macroscopically N0) or therapeutic (evident N1) lymph node dissection (LND) was performed. Other patients had a TT or partial thyroidectomy without LND. The mean follow-up time was 8.9 ± 8.8 years (median, 6.5 years; range, 1-36.4 years). RESULTS: A TT was performed in 2273 patients (90 %), including 1184 (52 %) with LND. Other patients (n = 245) had a single lobectomy with isthmectomy. Multifocality, bilaterality, number of tumors, sum of the largest size of all foci, vascular invasion, and (in patients with LND) LN metastases were significantly more frequent in T1b than in T1a patients. Of the 1184 patients with LND, 278 had LN metastases (N1, 23 %), including 136/680 T1a (20 %) and 142/504 (28 %) T1b patients (p = 0.002). These LN metastases were diagnosed after a prophylactic LND in 86/609 T1a (14 %) and 93/440 T1b (21 %) patients (p = 0.001). Recurrences were more frequent in T1b (n = 26, 3.8 %) than in T1a patients (n = 35, 1.9 %, p = 0.005). In the multivariate analysis, independent prognostic factors for recurrence in both groups were the number of tumors, the sum of the largest size of all foci and, in patients who had LND, LN metastases and extranodal extension. For N0-x patients, the recurrence rate was significantly higher in the T1b than in the T1a group (2.4 vs. 0.9 %, respectively, p = 0.005), although this rate was similar in N1 patients (16.2 % for T1a and 9.2 % for T1b patients, p = 0.1). The 5-year disease-free survival rates for T1a and T1b patients were 98.3 and 96.6 %, respectively (p = 0.01). CONCLUSION: For PTC patients, T1b had poorer clinicopathological features and increased risk of recurrence than T1a.

A novel technique for diaphragm biopsies in human patients.

BACKGROUND: The diaphragm is difficult to biopsy because of its anatomic location. We describe a new laparoscopic diaphragm biopsy technique. MATERIAL AND METHODS: Fifty one patients with amyotrophic lateral sclerosis gave their consent to diaphragm biopsy in the context of an implanted phrenic nerve stimulation protocol (NCT01583088). The biopsy was taken from the costal diaphragm, after opening the parietal peritoneum with scissors, and by grasping the diaphragmatic muscle over the rib with toothed laparoscopy forceps. RESULTS: The first four electrocoagulation biopsies were unsuitable for morphologic examination. The following 47 biopsies were therefore performed without electrocoagulation. The mean size of the biopsy fragments obtained after preparation was 3 ± 1 × 2 ± 1 × 1 ± 1 mm (maximum: 4 × 3 × 2 mm). A diaphragmatic injury occurred during the section in three cases requiring immediate suture without causing pneumothorax. A small pleural effusion was observed on the postoperative chest x-ray in one patient with a spontaneously favorable outcome. Numerous stains were able to be performed on the fragments obtained. CONCLUSIONS: Diaphragm biopsy can be safely performed by laparoscopy and yields tissue suitable for our future histologic evaluation.

Ambulatory thyroidectomy. Recommendations of the Association francophone de chirurgie endocrinienne (AFCE), with the Société française d'endocrinologie (SFE) and the Société française de médecine nucléaire (SFMN).

Before ambulatory thyroidectomy is proposed, the patient and his family and/or friends will need to be informed by the surgeon of the specificity of this procedure, the normal postoperative effects of a thyroidectomy, and potential complications. Also known as outpatient thyroid surgery, it can only be proposed by an experienced surgeon supported by an adequately trained medical and paramedical team. The healthcare establishment must be in possession of all the resources needed in ambulatory management, with continuity of care guaranteed 24h/24 7d/7 in the event of possible emergency rehospitalization. In all cases, contact the day after the operation between the healthcare facility and the patient is imperative. Ambulatory management can be proposed for lobo-isthmectomy or isthmectomy, possibly involving lymph node dissection. It is also possible for secondary totalization of thyroidectomy (following lobectomy). On the other hand, indications for single-stage total thyroidectomy must be limited and ensure proximity between the patient's home and a healthcare structure with a platform adapted to the pathology necessitating surgical intervention (non-plunging euthyroid goiter). A precise clinical pathway must be set out, including pre-, peri- and postoperative protocols having been formalized for surgery (hemostasis procedures) and for anesthesia (prevention of pain, of vomiting and of hypertension). We recommend at least 6hours of postoperative surveillance in outpatient care. When outpatient treatment is not possible or not recommended, hospitalization stay after thyroidectomy can be limited to 24hours, except in the event of postoperative complications, or a need for effectively dosed anticoagulant treatment.

Association of Autofluorescence-Based Detection of the Parathyroid Glands During Total Thyroidectomy With Postoperative Hypocalcemia Risk: Results of the PARAFLUO Multicenter Randomized Clinical Trial.

Importance: Because inadvertent damage of parathyroid glands can lead to postoperative hypocalcemia, their identification and preservation, which can be challenging, are pivotal during total thyroidectomy. Objective: To determine if intraoperative imaging systems using near-infrared autofluorescence (NIRAF) light to identify parathyroid glands could improve parathyroid preservation and reduce postoperative hypocalcemia. Design, Setting, and Participants: This randomized clinical trial was conducted from September 2016 to October 2018, with a 6-month follow-up at 3 referral hospitals in France. Adult patients who met eligibility criteria and underwent total thyroidectomy were randomized. The exclusion criteria were preexisting parathyroid diseases. Interventions: Use of intraoperative NIRAF imaging system during total thyroidectomy. Main Outcomes and Measures: The primary outcome was the rate of postoperative hypocalcemia (a corrected calcium <8.0 mg/dL [to convert to mmol/L, multiply by 0.25] at postoperative day 1 or 2). The main secondary outcomes were the rates of parathyroid gland autotransplantation and inadvertent parathyroid gland resection. Results: A total of 245 of 529 eligible patients underwent randomization. Overall, 241 patients were analyzed for the primary outcome (mean [SD] age, 53.6 [13.6] years; 191 women [79.3%]): 121 who underwent NIRAF-assisted thyroidectomy and 120 who underwent conventional thyroidectomy (control group). The temporary postoperative hypocalcemia rate was 9.1% (11 of 121 patients) in the NIRAF group and 21.7% (26 of 120 patients) in the control group (between-group difference, 12.6% [95% CI, 5.0%-20.1%]; P = .007). There was no significant difference in permanent hypocalcemia rates (0% in the NIRAF group and 1.6% [2 of 120 patients] in the control group). Multivariate analyses accounting for center and surgeon heterogeneity and adjusting for confounders, found that use of NIRAF reduced the risk of hypocalcemia with an odds ratio of 0.35 (95% CI, 0.15-0.83; P = .02). Analysis of secondary outcomes showed that fewer patients experienced parathyroid autotransplantation in the NIRAF group than in the control group: respectively, 4 patients (3.3% [95% CI, 0.1%-6.6%) vs 16 patients (13.3% [95% CI, 7.3%-19.4%]; P = .009). The number of inadvertently resected parathyroid glands was significantly lower in the NIRAF group than in the control group: 3 patients (2.5% [95% CI, 0.0%-5.2%]) vs 14 patients (11.7% [95% CI, 5.9%-17.4%], respectively; P = .006). Conclusions and Relevance: The use of NIRAF for the identification of the parathyroid glands may help improve the early postoperative hypocalcemia rate significantly and increase parathyroid preservation after total thyroidectomy. Trial Registration: ClinicalTrials.gov Identifier: NCT02892253.

Prognosis of papillary thyroid carcinoma in elderly patients after thyroid resection: A retrospective cohort analysis.

The size of the elderly population and the incidence of papillary thyroid carcinoma (PTC) in this group appear to be rapidly increasing, although published information based on more detailed older age groupings are lacking.This study aimed to determine the clinical features and outcomes of elderly patients in PTC.All consecutive patients who received surgery for PTC in our Department from 1978 to 2014 were included. We compared 3 patient groups: young (<65 years), older (65-75 years), and very old patients (>75 years). Total thyroidectomy was performed with lymph node (LN) dissection in most cases, and radioiodine therapy was administered as needed.A total of 3835 patients (3257 young patients, 450 older patients, and 128 very old patients) were identified. Very old patients were more likely to have advanced (III/IV) tumor, nodes, metastases (TNM) stage, greater tumor size, number of tumors, and extracapsular invasion compared with young and older patients. For the 2289 patients with LN dissection (60%), metastatic LNs were more frequent in the very old group (44%) than in the other groups (34% young and 33% older patients) (P = 0.01). Very old patients had more frequent distant metastases (5%) than the older (2%) and young groups (1%) (P < 0.001). The overall postoperative morbidity was not significantly different between the 3 age groups. Recurrence was documented in 202 (6.2%) young, 29 (6.4%) older, and 15 (11.7%) very old PTC patients (P = 0.04). The 5-year disease-free survival was 81.3% for very old, 92.9% for older, and 94.7% for young group (P < 0.001).Very old patients should be considered high-risk PTC patients and their therapeutic strategy may benefit from aggressive treatment.

How to Avoid Nontherapeutic Laparotomy in Patients With Multiple Organ Failure of Unknown Origin. The Role of CT Scan Revisited.

Diagnosis of intra-abdominal diseases in critically ill patients remains a clinical challenge. Physical examination is unreliable whereas exploratory laparotomy may aggravate patient's condition and delay further evaluation. Only a few studies have investigated the place of computed tomography (CT) on this hazardous situation. We aimed to evaluate the ability of CT to prevent unnecessary laparotomy during the management of critically ill patients. Charts of all consecutive patients who had undergone an emergency nontherapeutic laparotomy from 1996 to 2013 were retrospectively studied and patient's demographic, clinical characteristics, and surgical findings were collected. During this period 59 patients had an unnecessary laparotomy. Fifty-one patients had at least one preoperative imaging and 36 had a CT scan. CT scans were interpreted to be normal (n = 12), with minor anomalies (n = 10), or major anomalies (pneumoperitoneum, portal venous gas/pneumatosis intestinalis, thickened gallbladder wall, and small bowel obstruction signs). Surgical exploration was performed through laparotomy (n = 55) or laparoscopy. Overall mortality was 37% with a median survival after surgery of 7 days. In univariate analysis, hospitalization in ICU before surgical exploration was the only factor related to death. In our series CT scans, objectively interpreted, helped avoid unnecessary surgical exploration in 61% of our patients.

Ischaemic colitis: indications, extent, and results of standardized emergency surgery.

BACKGROUND: Acute ischaemic colitis can occur postoperatively, mainly after aortic surgery, or spontaneously. Surgical treatment is debated. Study aim was to describe factors related to ischaemic colitis severity, determine if postoperative and spontaneous ischaemic colitis share similar outcomes, and evaluate results of standardized management. METHODS: 191 consecutive cases of ischaemic colitis observed from 1997 to 2012 were retrospectively analyzed: 119 (62%) after surgery and 72 (38%) spontaneous. Colon resection was performed for endoscopic type 2 colitis with multiple organ failure, and for every type 3. Types 1 and 2 without multiple organ failure were managed nonoperatively. RESULTS: Seventeen patients (9%) were managed nonoperatively, without mortality. Mortality rate after resection was 48% (84/174), within 9 days (range, 0-152). Multivariate analysis found 2 independent factors associated with postoperative death: age≥75 years and multiple organ failure. The context in which ischaemic colitis occurred was not a risk factor for mortality. Mortality rates were 51% for final type 3 (66% with multiple organ failure, 17% without), 53% for final type 2 with multiple organ failure, and 0% for type 1 or type 2 without multiple organ failure. CONCLUSION: An aggressive surgical approach in patients with ischaemic colitis seems justified in patients with multiple organ failure and findings of severe form of ischaemia at endoscopy.

Optimal nonsurgical management of peptic ulcer bleeding, including arterial embolization is associated with a mortality below 1%.

BACKGROUND: Management of high-risk peptic ulcer bleeding (PUB) consists in a high-dose infusion of proton pump inhibitors (PPIs) with double endoscopic treatment. If bleeding recurs, a second endoscopic treatment is required. Surgical management should be performed in case of endoscopic treatment failure, or if a second rebleeding occurs. Arterial embolization of PUB has been shown efficient and safe in small retrospective series, but optimal medical treatment was not used. OBJECTIVE: Prospective assessment of the feasibility and the efficacy of arterial embolization of endoscopically unmanageable PUB, after optimal medical treatment. PATIENTS: All consecutive patients referred to our intensive care unit (ICU) for high-risk PUB received high-dose PPIs and underwent double endoscopic treatment when possible. Arterial embolization was proposed in primary failure to endoscopic treatment, in case of failure of the second endoscopic treatment, or if a second recurrence occurred. RESULTS: One hundred and twenty-eight patients with PUB were enrolled between January 2008 and December 2009. Arterial embolization, performed in 11 patients, was efficient in nine patients. Surgery was performed in two patients (one after inefficient embolization, and one with embolization-related complication). One patient died during hospitalization. CONCLUSION: Arterial embolization seems to be efficient for endoscopically unmanageable PUB. In our series, one patient developed severe complication related to the procedure and died. If arterial embolization could be proposed before surgery in case of refractory PUB, large prospective studies are needed.

Improved retroviral suicide gene transfer in colon cancer cell lines after cell synchronization with methotrexate.

BACKGROUND: Cancer gene therapy by retroviral vectors is mainly limited by the level of transduction. Retroviral gene transfer requires target cell division. Cell synchronization, obtained by drugs inducing a reversible inhibition of DNA synthesis, could therefore be proposed to precondition target cells to retroviral gene transfer. We tested whether drug-mediated cell synchronization could enhance the transfer efficiency of a retroviral-mediated gene encoding herpes simplex virus thymidine kinase (HSV-tk) in two colon cancer cell lines, DHDK12 and HT29. METHODS: Synchronization was induced by methotrexate (MTX), aracytin (ara-C) or aphidicolin. Gene transfer efficiency was assessed by the level of HSV-TK expression. Transduced cells were driven by ganciclovir (GCV) towards apoptosis that was assessed using annexin V labeling by quantitative flow cytometry. RESULTS: DHDK12 and HT29 cells were synchronized in S phase with MTX but not ara-C or aphidicolin. In synchronized DHDK12 and HT29 cells, the HSV-TK transduction rates were 2 and 1.5-fold higher than those obtained in control cells, respectively. Furthermore, the rate of apoptosis was increased two-fold in MTX-treated DHDK12 cells after treatment with GCV. CONCLUSIONS: Our findings indicate that MTX-mediated synchronization of target cells allowed a significant improvement of retroviral HSV-tk gene transfer, resulting in an increased cell apoptosis in response to GCV. Pharmacological control of cell cycle may thus be a useful strategy to optimize the efficiency of retroviral-mediated cancer gene therapy.

Fatty pancreas and increased body mass index are risk factors of pancreatic fistula after pancreaticoduodenectomy.

BACKGROUND: Pancreatic fistula (PF) after pancreatoduodenectomy (PD) remains a challenging problem. The only commonly accepted risk factor is the soft consistency of the pancreatic remnant. METHODS: In all, 100 consecutive patients underwent PD. All data, including commonly accepted risk factors for PF and PF defined according to the International Study Group of Pancreatic Fistula, were collected prospectively. On the pancreatic margin, a score of fibrosis and a score of fatty infiltration were assessed by a pathologist blinded to the postoperative course. RESULTS: PF occurred in 31% of patients. In univariate analysis, male sex, age greater than 58 years, body mass index (BMI) > or =25 kg/m(2), pre-operative high blood pressure, operation for nonintraductal papillary and mucinous neoplasm (IPMN) disease and for ampullary carcinoma, operative time, blood loss, soft consistency of the pancreatic remnant, absence of pancreatic fibrosis, and presence of fatty infiltration of the pancreas were associated with a greater risk of PF. In a multivariate analysis, only BMI > or =25 kg/m(2), absence of pancreatic fibrosis, and presence of fatty pancreas were significant predictors of PF. A score based on the number of risk factors present divided the patient population into 4 subgroups carrying a risk of PF that ranged from 7% (no risk factor) to 78% (3 risk factors) and from 0% to 81%, taking into account only symptomatic PF (grade B and C). CONCLUSION: The presence of an increased BMI, the presence of fatty pancreas, and the absence of pancreatic fibrosis as risk factors of PF allows a more precise and objective prediction of PF than the consistency of pancreatic remnant alone. A predictive score based on these 3 factors could help to tailor preventive measures.

Primary hyperparathyroidism from parathyroid microadenoma: specific features and implications for a surgical strategy in the era of minimally invasive parathyroidectomy.

BACKGROUND: The aim of this study was to identify the specific preoperative characteristics of patients with parathyroid microadenoma and to report their outcomes after surgical treatment. STUDY DESIGN: Parathyroid microadenomas (weight < 100 mg) were identified in 62 (6%) of the 1,012 patients operated on for a parathyroid adenoma between 1995 and 2004. Presentation and outcomes after surgery were compared with those of 124 patients operated on consecutively for parathyroid adenoma (>100 mg) during the last year of the study. All patients underwent bilateral surgical exploration of the neck. Success was defined as resection of a pathologic gland combined with normocalcemia at 6 months after operation. Logistic regression was used to test the relationship between groups and potential predictive factors of microadenoma. RESULTS: There were 57 women (92%) and the median age was 57 years (range 29 to 77 years). Median preoperative calcemia and parathyroid hormone (PTH) serum levels were 2.64 mmol/L (range 2.31 to 3 mmol/L) and 79 pg/mL (range 30 to 189 pg/mL), respectively. There was no difference in the clinical presentation between patients with microadenoma and adenoma. Preoperative calcium (p < 0.001) and PTH serum levels (p = 0.014) were significantly higher in patients with adenoma. Calcium and PTH serum levels lower than 2.6 mmol/L and 60 pg/mL, respectively, predicted the presence of microadenoma with respective specificities of 0.89 and 0.87. Success rates were similar in the microadenoma and adenoma groups (92% vs 98%; p = 0.11). CONCLUSIONS: Mild preoperative elevations of calcium or PTH serum levels should warn about the risk of microadenoma. In this setting, intraoperative difficulties should be expected in identifying the pathologic gland, and bilateral neck exploration should be the preferred surgical approach.