Performance of a multigene genomic classifier and clinical parameters in predicting malignancy in a Southeast Asian cohort of patients with cytologically indeterminate thyroid nodules

BACKGROUND

Most thyroid nodules are benign. It is important to determine the likelihood of malignancy in such nodules to avoid unnecessary surgery. The primary objective of this study was to characterize the genetic landscape and the performance of a multigene genomic classifier in fine-needle aspiration (FNA) biopsies of cytologically indeterminate thyroid nodules in a Southeast Asian cohort. The secondary objective was to assess the predictive contribution of clinical characteristics to thyroid malignancy.

METHODS

This prospective, multicenter, blinded study included 132 patients with 134 nodules. Molecular testing (MT) with ThyroSeq v3 was performed on clinical or ex-vivo FNA samples. Centralized pathology review also was performed.

RESULTS

Of 134 nodules, consisting of 61% Bethesda category III, 20% category IV, and 19% category V cytology, and 56% were histologically malignant. ThyroSeq yielded negative results in 37.3% of all FNA samples and in 42% of Bethesda category III-IV cytology nodules. Most positive samples had RAS-like (41.7%), followed by BRAF-like (22.6%), and high-risk (17.9%) alterations. Compared with North American patients, the authors observed a higher proportion of RAS-like mutations, specifically NRAS, in Bethesda categories III and IV and more BRAF-like mutations in Bethesda category III. The test had sensitivity, specificity, negative predictive value, and positive predictive value of 89.6%, 73.7%, 84.0%, and 82.1%, respectively. The risk of malignancy was predicted by positive MT and high-suspicion ultrasound characteristics according to American Thyroid Association criteria.

CONCLUSIONS

Even in the current Southeast Asian cohort with nodules that had a high pretest cancer probability, MT could lead to potential avoidance of diagnostic surgery in 42% of patients with Bethesda category III-IV nodules. MT positivity was a stronger predictor of malignancy than clinical parameters.

Minimally invasive video-assisted thyroidectomy in Asian patients: experience from Singapore

BACKGROUND

Minimally invasive video-assisted thyroidectomy (MIVAT) although well established in Europe has not yet gained widespread acceptance in Asia. We describe our learning experience in the first reported series of 105 cases from Singapore.

METHODS

A retrospective analysis of outcomes in 105 patients who underwent MIVAT from April 2011 to 2018 was performed. The inclusion criteria were - symptomatic benign thyroid pathologies and follicular lesions or neoplasms needing a hemi-thyroidectomy. A thyroid lobe volume less than 35 mL was used as cut-off. Patients underwent surgeon-performed thyroid ultrasound with biopsy of solid nodules. All cases were operated by one surgeon using standard Miccoli technique with energy device used in all cases.

RESULTS

From a total of 424 patients with nodular goitres undergoing thyroidectomy, 105 (24%) symptomatic eligible patients underwent the MIVAT procedure (M:F - 23:82). The mean incision lengths at start and completion were 1.7 cm (range 1.5-2 cm) and 2.4 cm (range 2-2.7 cm), respectively. Mean operating time was 97 min (range 59-160 min). There were four conversions (3.8%) in the first 25 cases and four patients (3.8%) experienced transient hoarseness with full recovery. Visual analogue pain scores at 6 and 24 h post-operatively were 2.7 and 1.1, respectively. Scar satisfaction was reported as excellent (75%), satisfactory (23%) and poor (2%).

CONCLUSION

Although technically more demanding, MIVAT is a safe and useful operation in a thyroid surgeon's armamentarium. The limitation of goitre size, however, allows only a small percentage of symptomatic patients to undergo this procedure.

The lateral "backdoor" approach to open thyroid surgery: A comparative study

INTRODUCTION

The traditionally taught technique for conventional open thyroidectomy is via a midline splitting of the strap muscles following a skin crease neck incision - midline approach (MA). The lateral "backdoor" approach (LA) uses the same central neck incision but approaches the thyroid gland between the anterior border of sternocleidomastoid (SCM) and strap muscles. This technique is usually reserved for re-do thyroid surgery. We compared the results of the two approaches in patients undergoing conventional thyroidectomy for the first time.

METHODS

A case-control study was performed on 90 patients undergoing conventional open thyroidectomy from 2012 to 2014. The first 45 patients underwent MA and subsequent 45 patients underwent LA. All patients were given 10 ml of 1% Marcaine infiltration into the neck incision before closure. Basic demographic data, operative time, incision length, weight of gland, need for transection of strap muscles and complications were recorded. Revision thyroid surgery and minimally invasive thyroid operations were excluded.

RESULTS

The demographics, operative timing, gland weight and incisional length showed no significant difference. Post-operative pain was significantly lower in the LA group. 5 patients (11%) in MA group needed horizontal transection of strap muscles to extract large goitres compared to 1 patient (2.2%) in the LA group. No major complications occurred in either group.

CONCLUSION

The LA method is as safe as the midline technique with comparable operative time and significantly lower pain scores. It avoids midline separation and suturing of strap muscles and reduces the need for strap muscle transection to removal large goitres.

Video-assisted bilateral neck exploration in patients with primary hyperparathyroidism and failed localization studies

BACKGROUND

In primary hyperparathyroidism (pHPT) positive preoperative localization studies are accepted as a precondition for applying minimally invasive surgical techniques. Without localization, open bilateral neck exploration (BNE) is considered the standard option. The present study analyzes the feasibility and effectiveness of minimally invasive video-assisted BNE in patients with pHPT and negative or discordant localization studies.

METHODS

From a prospective series of 380 minimally invasive video-assisted parathyroidectomies (MIVAP) performed in 367 patients for pHPT (1999-2009), 68 patients (10 male, 58 female; mean age: 58 years) were selected. These patients had failed localization studies and underwent BNE with the MIVAP technique. Operative time, complications, conversions to open technique, and cure rate were determined.

RESULTS

Mean operative time was 52 +/- 26 min (range: 20-180 min). MIVAP with BNE was successfully completed in 66 (97%) patients with two conversions to open technique. Recurrent laryngeal nerve palsy occurred in one patient. Biochemical cure was achieved in 67 patients (98.5%), in 65 patients (95.5%) after the first operation and in two more patients by video-assisted re-exploration on the first postoperative day. One patient remained with persistent disease even after repeated open BNE.

CONCLUSIONS

In experienced hands, video-assisted BNE with the MIVAP technique, for pHPT and failed localization studies, is feasible, safe, and gives results equivalent to the conventional open technique.

Acute abdominal pain secondary to retroperitoneal bleeding from a giant adrenal lipoma with review of literature

Adrenal lipomas are rare, non-functioning benign tumours, which are primarily detected during autopsy or imaging, as asymptomatic incidentalomas. Occasionally, they can present with abdominal pain due to their large size. Imaging studies help to determine the origin, volume, composition of the lesion and presence of bleeding. Histopathology, however, is necessary to differentiate an adrenal lipoma from other fatty tumours such as myelolipoma, angiomyolipomas, teratomas and liposarcomas. We report a case of spontaneous bleeding from a giant adrenal lipoma that presented as an acute abdomen, and was initially mistaken on imaging for the more common myelolipoma. The literature is reviewed to discuss the clinical, pathological and radiological features, and the optimum therapeutic management.

Laparoscopic duodenojejunostomy for superior mesenteric artery syndrome

BACKGROUND

Superior mesenteric artery syndrome (SMAS) is a rare condition causing acute or chronic compression of the third part of the duodenum, due to a reduction in the aortomesenteric angle. Traditionally, an open duodenojejunostomy is recommended when conservative management fails. Laparoscopic duodenojejunostomy is a minimally invasive option that has been reported in up to 10 cases. We describe our operative technique in one case and review the literature on this condition.

METHODS

A previously well 66-year-old man presented with acute gastric dilatation. An abdominal computerized tomography (CT) scan and oral Gastrografin meal revealed a dilated stomach and proximal duodenum due to compression of the third part of the duodenum between the superior mesenteric artery (SMA) and aorta.

RESULTS

Esophagogastroduodenoscopy (EGD) ruled out intraluminal causes. A laparoscopic duodenojejunostomy was performed when conservative management failed. Postoperative recovery was quick and uneventful. Gastrografin administration on the fifth day showed no leak, with free flow of contrast into the jejunum. The patient resumed a normal diet and remained asymptomatic at 6-month follow-up.

CONCLUSION

Laparoscopic duodenojejunostomy is feasible, safe, and effective. It gives the same results as open surgery with all the advantages of minimally invasive surgery.

Use of endoscopic snare to extract a large rectosigmoid foreign body with review of literature

Rectal foreign bodies are common and various shapes and sizes have been described in literature. Large objects impacted high in the rectosigmoid junction pose a challenge for endoscopic extraction. We describe a method that successfully removed a 15x6x3.5-cm shampoo bottle impacted in the rectosigmoid junction. A 50-year-old man had passed a shampoo bottle up into his rectum. Examination revealed a lax sphincter but the bottle could not be felt. Contrast x-rays showed a well-delineated bottle in the rectosigmoid junction with no evidence of bowel perforation. A flexible sigmoidoscope with an endoscopic snare was used to "lasso" the foreign body and deliver it out. A check sigmoidoscopy after extraction showed no bleeding or perforation. This technique is a safer and less morbid method of extracting impacted high rectal foreign bodies, in the absence of perforation. It should be attempted before open surgical removal.

Is this a variant of Lemierre's syndrome?

Lemierre's syndrome is an oropharyngeal infection leading to secondary septic thrombophlebitis of the internal jugular vein (IJV). It is classically anaerobic in origin and Fusobacterium necrophorum is the commonest pathogen. We report an unusual variant of this condition in a 68-year-man with uncontrolled diabetes mellitus who presented with extensive cellulitis of the left neck. No primary oropharyngeal sepsis was detected. Neck radiographs revealed soft tissue gas and computed tomography confirmed neck space infection with gas formation and complete thrombosis of the left IJV. Klebsiella pneumoniae was isolated from the fluid, tissue and blood samples. Repeated debridement was required until complete healing. Computed tomography of the neck at six months showed resolution of infection, although the vein remained thrombosed. Although the radiological features resemble Lemierre's syndrome, this case differs from it in the absence of oropharyngeal sepsis and presence of background diabetes mellitus. The isolation of Klebsiella pneumoniae as a cause has not been previously described.