High-Grade Neuroendocrine Carcinoma Within a Tracheal Polyp: A Case Report

Introduction

Primary carcinomas of the trachea are rare, with a reported annual incidence of one in a million. We present a case of a previously undescribed polypoid high-grade neuroendocrine carcinoma of the trachea. Resection of the carcinoma revealed only superficial invasion of the mucosa and without evidence of local or distant metastatic disease. Histologically, the tumor had high-grade features with necrosis and a high mitotic index.

Methods

Characterization of this rare neuroendocrine carcinoma of the trachea was performed by immunohistochemistry and whole-genome sequencing.

Results

Immunohistochemistry result was positive for neuroendocrine markers, p16 and an elevated Ki-67. Whole-genome sequencing of the lesion was performed and revealed a very unusual and very distinct mutational signature without relationship to other relevant neuroendocrine carcinomas. Neither known driver nor targetable mutations were found by whole-genome sequencing. Analysis of the sequence of numerous viral elements of human papillomavirus-18 suggests that the pathogenesis of the lesion is related to viral integration. The patient developed distal recurrence, which progressed to widespread pulmonary dissemination, presumably through aerogenous spread of disease.

Conclusions

This is the first characterization of this type of tracheal tumor, including genomic findings, pathogenesis, and natural history.

Oncosuppressor-Mutated Cell-Based Diagnostic Platform for Liquid Biopsy Diagnoses Benign Head and Neck Masses and Predicts Malignancy in Thyroid Nodules: Results from a Consecutive Cohort of Patients

BACKGROUND

We reported that a novel oncosuppressor-mutated cell (OMC)-based platform has the potential for early cancer detection in healthy individuals and for identification of cancer patients at risk of developing metachronous metastases.

OBJECTIVE

Herein, we sought to determine the diagnostic accuracy of this novel OMC-based platform in a consecutive cohort of patients operated for suspicious head and neck masses.

METHODS

OMCs (BRCA1-deficient fibroblasts) were exposed to blood serum from patients with head and neck nodules before surgical removal. These cells were analyzed for their proliferation and survival. Treated OMCs were inoculated subcutaneously in NOD/SCID mice, and tumor growth was monitored over time.

RESULTS

OMCs exposed to serum from patients with malignant lesions displayed increased proliferation compared to those exposed to serum from patients with benign lesions. Only OMCs exposed to serum from patients diagnosed with malignant thyroid neoplasia generated a cancerous mass. The sensitivity of the test was 92%, with only 1 false negative out of 34 patients. Immunohistochemical staining showed that the cancerous masses were poorly differentiated adenocarcinomas with high proliferative index.

CONCLUSIONS

These data show that liquid biopsy combined with an OMC-based in vivo platform has the potential to diagnose benign head and neck masses and predict whether a thyroid nodule is malignant. These results strengthen the concept that OMCs can be used to detect circulating malignant factors in cancer patients.

A thyroid gland with over 30 foci of papillary thyroid carcinoma with activating BRAF V600E mutation

Multifocal papillary thyroid carcinoma (PTC) is common and the number of tumor foci rarely exceeds ten. The mechanism of multifocal disease is debated, with the two main hypotheses consisting of either intrathyroidal metastatic spread from a single tumor or independent multicentric tumorigenesis from distinct progenitor cells. We report the case of a 46-year-old woman who underwent total thyroidectomy and left central neck lymph node dissection after fine-needle aspiration of bilateral thyroid nodules that yielded cytological findings consistent with PTC. Final pathology of the surgical specimen showed an isthmic dominant 1.5 cm classical PTC and over 30 foci of microcarcinoma, which displayed decreasing density with increasing distance from the central lesion. Furthermore, all malignant tumors and lymph nodes harbored the activating BRAF V600E mutation. The present case highlights various pathological features that support a mechanism of intraglandular spread, namely a strategic isthmic location of the primary tumor, radial pattern of distribution and extensive number of small malignant foci and BRAF mutational homogeneity. Learning points: Multifocal papillary thyroid carcinoma (PTC) is commonly seen in clinical practice, but the number of malignant foci is usually limited to ten or less. There is no clear consensus in the literature as to whether multifocal PTC arises from a single or multiple distinct tumor progenitor cells. Strategic location of the dominant tumor in the thyroid isthmus may favor intraglandular dissemination of malignant cells by means of the extensive lymphatic network. An important pathological finding that may be suggestive of intrathyroidal metastatic spread is a central pattern of distribution with a reduction in the density of satellite lesions with increasing distance from the dominant focus. PTCs originating from the isthmus with intraglandular metastatic dissemination behave more aggressively. As such, a more aggressive treatment course may be warranted, particularly with regard to the extent of surgery.

Primitive Neuroectodermal Tumor (PNET) as Somatic-Type Malignancy Arising from an Extragonadal Germ-Cell Tumor: Clinical, Pathological and Molecular Features of a Case

We report a rare case of a 34-year-old man with a right axillary mass. Ten years previously, he had been diagnosed with a right scapular nonseminomatous germ-cell tumor consisting of teratoma, completely resected without any further treatment. Presently he was found to have a metastatic malignant small round cell tumor consistent with a secondary somatic malignancy arising in the background of nonseminomatous germ-cell tumor, teratoma, yolk sac tumor, and primitive neuroectodermal tumor with distinct chromosome 22 translocation. Although the patient initially responded well to chemotherapy with etoposide, cisplatin, ifosfamide and mesna, he relapsed shortly after.

Measuring Decision-Making During Thyroidectomy: Validity Evidence for a Web-Based Assessment Tool

BACKGROUND

Errors in judgment during thyroidectomy can lead to recurrent laryngeal nerve injury and other complications. Despite the strong link between patient outcomes and intraoperative decision-making, methods to evaluate these complex skills are lacking. The purpose of this study was to develop objective metrics to evaluate advanced cognitive skills during thyroidectomy and to obtain validity evidence for them.

METHODS

An interactive online learning platform was developed ( www.thinklikeasurgeon.com ). Trainees and surgeons from four institutions completed a 33-item assessment, developed based on a cognitive task analysis and expert Delphi consensus. Sixteen items required subjects to make annotations on still frames of thyroidectomy videos, and accuracy scores were calculated based on an algorithm derived from experts' responses ("visual concordance test," VCT). Seven items were short answer (SA), requiring users to type their answers, and scores were automatically calculated based on their similarity to a pre-populated repertoire of correct responses. Test-retest reliability, internal consistency, and correlation of scores with self-reported experience and training level (novice, intermediate, expert) were calculated.

RESULTS

Twenty-eight subjects (10 endocrine surgeons and otolaryngologists, 18 trainees) participated. There was high test-retest reliability (intraclass correlation coefficient = 0.96; n = 10) and internal consistency (Cronbach's α = 0.93). The assessment demonstrated significant differences between novices, intermediates, and experts in total score (p < 0.01), VCT score (p < 0.01) and SA score (p < 0.01). There was high correlation between total case number and total score (ρ = 0.95, p < 0.01), between total case number and VCT score (ρ = 0.93, p < 0.01), and between total case number and SA score (ρ = 0.83, p < 0.01).

CONCLUSION

This study describes the development of novel metrics and provides validity evidence for an interactive Web-based platform to objectively assess decision-making during thyroidectomy.

Defining competencies for safe thyroidectomy: An international Delphi consensus

BACKGROUND

Current methods for teaching and assessing competencies that characterize expert intraoperative performance are inconsistent, subjective, and lack standardization. This mixed-methods study was designed to define and establish expert consensus on the most important competencies required to perform a thyroidectomy safely.

METHODS

Cognitive task analyses for thyroidectomy were performed with semistructured interviews of experts in thyroid surgery. Verbal data were transcribed verbatim, coded, and categorized according to themes that were synthesized into a list of items. Once qualitative data reached saturation, 26 experts were invited to complete 2-round online Delphi surveys to rank each item on a Likert scale of importance (1-7). Consensus was predefined as a Cronbach's α ≥ 0.80.

RESULTS

Sixty items were synthesized from 5 interviews and categorized into 8 sections: preparation (n = 8), incision/exposure (n = 11), general considerations (n = 4), middle thyroid vein (n = 1), superior pole (n = 5), inferior pole (n = 5), posterolateral dissection (n = 19), and closure (n = 7). Eighteen (69%) experts from 3 countries participated in the Delphi survey. Consensus was achieved after 2 voting rounds (Cronbach's α = 0.95). Greatest weighted sections included "Superior Pole Dissection" and "Posterolateral Dissection."

CONCLUSION

Consensus was achieved on defining the most important competencies for safe thyroidectomy. This blueprint serves as the basis for instructional design and objective assessment tools to evaluate performance.

Parathyroid hormone levels 1 hour after thyroidectomy: an early predictor of postoperative hypocalcemia

BACKGROUND

Parathyroid dysfunction leading to symptomatic hypocalcemia is not uncommon following a total or completion thyroidectomy and is often associated with significant patient morbidity and a prolonged hospital stay. A simple, reliable indicator to identify patients at risk would permit earlier pharmacologic prophylaxis to avoid these adverse outcomes. We examined the role of intact parathormone (PTH) levels 1 hour after surgery as a predictor of post-thyroidectomy hypocalcemia.

METHODS

We prospectively reviewed the cases of consecutive patients undergoing total or completion thyroidectomy. Ionized calcium (Ca(2+)) and intact PTH levels were measured preoperatively and at 1-, 6- and 24-hour intervals postoperatively. The specificity, sensitivity, negative and positive predictive values of the 1-hour PTH serum levels (PTH-1) in predicting 24-hour post-thyroidectomy hypocalcemia and eucalcemia were determined.

RESULTS

We reviewed the cases of 149 patients. Biochemical hypocalcaemia (Ca(2+) < 1.1 mmol/L) developed in 38 of 149 (25.7%) patients 24 hours after thyroidectomy. The sensitivity, specificity, positive and negative predictive values of a low PTH-1 were 89%, 100%, 97% and 100%, respectively.

CONCLUSION

We found that PTH-1 levels were predictive of symptomatic hypocalcemia 24 hours after thyroidectomy. Routine use of this assay should be considered, as it could prompt the early administration of calcitriol in patients at risk of hypocalcemia and allow for the safe and timely discharge of patients expected to remain eucalcemic.

Rare metastases of well-differentiated thyroid cancers: a systematic review

BACKGROUND

A minority of metastatic well-differentiated thyroid cancer (WDTC) patients present with end-organ disease other than in the lung, bone or lymph nodes. These metastases tend to be overlooked because of their low incidence, and this results in delayed diagnosis. The purpose of this study was to perform a systematic review of the clinical and histologic features of unusual WDTC metastases.

METHODS

A systematic literature search of bibliographic databases, reference lists of articles, and conference proceedings was performed up to 2013. Studies were included if they reported on adult patients with WDTC and pathology-proven metastases to end-organs other than lung, bone, or lymph nodes. A total of 238 studies were included in a qualitative analysis. Data is expressed as N (%) and median [interquartile range].

RESULTS

A total of 492 patients (median age, 62 years [50-70 years]) were identified in 197 case reports and 42 case series. There were 22 different end-organ metastatic sites documented with either papillary [255 (57 %)], follicular [172 (39 %)], or Hürthle-cell [18 (4 %)] histology. A total of 181 (41 %) patients presented with solitary metastasis and 54 (93 %) with elevated serum thyroglobulin. Positron emission tomography and whole-body radioactive iodine scans revealed hypermetabolic foci in 28 (97 %) and 50 (81 %) cases, respectively. Disease-free interval following the initial diagnosis of the primary thyroid cancer was highly variable, ranging from synchronous presentation [66 (33 %)] to metachronous disease after 516 months [mean 86 months (SD 90)].

CONCLUSIONS

WDTC can manifest with highly variable and unusual clinical features. Rare sites of metastases should be considered in the absence of the more common extra-cervical disease recurrence locations.

A multi-institutional international study of risk factors for hematoma after thyroidectomy

BACKGROUND

Cervical hematoma can be a potentially fatal complication after thyroidectomy, but its risk factors and timing remain poorly understood.

METHODS

We conducted a retrospective, case-control study identifying 207 patients from 15 institutions in 3 countries who developed a hematoma requiring return to the operating room (OR) after thyroidectomy.

RESULTS

Forty-seven percent of hematoma patients returned to the OR within 6 hours and 79% within 24 hours of their thyroidectomy. On univariate analysis, hematoma patients were older, more likely to be male, smokers, on active antiplatelet/anticoagulation medications, have Graves' disease, a bilateral thyroidectomy, a drain placed, a concurrent parathyroidectomy, and benign pathology. Hematoma patients also had more blood loss, larger thyroids, lower temperatures, and higher blood pressures postoperatively. On multivariate analysis, independent associations with hematoma were use of a drain (odds ratio, 2.79), Graves' disease (odds ratio, 2.43), benign pathology (odds ratio, 2.22), antiplatelet/anticoagulation medications (odds ratio, 2.12), use of a hemostatic agent (odds ratio, 1.97), and increased thyroid mass (odds ratio, 1.01).

CONCLUSION

A significant number of patients with a postoperative hematoma present >6 hours after thyroidectomy. Hematoma is associated with patients who have a drain or hemostatic agent, have Graves' disease, are actively using antiplatelet/anticoagulation medications or have large thyroids. Surgeons should consider these factors when individualizing patient disposition after thyroidectomy.

Primitive neuroectodermal tumor (PNET) as somatic-type malignancy arising from an extragonadal germ-cell tumor: clinical, pathological and molecular features of a case

We report a rare case of a 34-year-old man with a right axillary mass. Ten years previously, he had been diagnosed with a right scapular nonseminomatous germ-cell tumor consisting of teratoma, completely resected without any further treatment. Presently he was found to have a metastatic malignant small round cell tumor consistent with a secondary somatic malignancy arising in the background of nonseminomatous germ-cell tumor, teratoma, yolk sac tumor, and primitive neuroectodermal tumor with distinct chromosome 22 translocation. Although the patient initially responded well to chemotherapy with etoposide, cisplatin, ifosfamide and mesna, he relapsed shortly after.

Incidental thyroid "PETomas": clinical significance and novel description of the self-resolving variant of focal FDG-PET thyroid uptake

BACKGROUND

Recent series of incidental thyroid activity on fluorodeoxyglucose positron emission tomography (FDG-PET) in patients evaluated for nonthyroidal malignancy, which we refer to as a "PEToma," have suggested that such lesions are associated with a significant incidence of primary thyroid cancer.

METHODS

We retrospectively reviewed 6457 FDG-PET scans performed on 4726 patients from May 2004 to March 2007. We reviewed the cases of patients whose PET or computed tomography (CT) radiology reports described PET uptake within the thyroid to identify incidence and malignant potential of PETomas and evaluate their clinical and histopathologic features.

RESULTS

We found that 160 patients (3.4%) had incidental, abnormal FDG uptake in the thyroid gland, 103 of whom had focal uptake (the PEToma group). Of these patients, 50 (48%) underwent further investigations, including ultrasonography in 48, fine-needle aspiration cytology in 38 and computed tomography in 3. Ten patients underwent surgery, and papillary thyroid cancer was identified in 9. The remaining 53 patients with PETomas underwent no further investigation. Interestingly, 5 patients who had focal uptake within the thyroid showed either spontaneous resolution on repeat FDG-PET (self-resolving) or no focal lesion on subsequent ultrasonography (false-positive).

CONCLUSION

The incidence of papillary thyroid cancer in the present series is similar to that in the literature. Although some patients will show self-resolving or false-positive focal thyroid uptake on FDG-PET, we believe that, if the patient's clinical status permits, the evaluation of patients with incidental thyroid PEToma should include ultrasonographic confirmation and fine-needle aspiration cytology.

Radio-guided minimally invasive parathyroidectomy under local anesthesia

BACKGROUND

Despite the high success rate of the complete bilateral neck exploration to treat primary hyperparathyroidism, less invasive alternatives have been emerging. In an attempt to reduce operative time and decrease perioperative morbidity, we reported our experience with radio-guided minimally invasive parathyroidectomy (RMIP) under local anesthesia.

STUDY DESIGN

A retrospective chart review was carried out to study 55 consecutive patients, in an adult tertiary care hospital (Montreal General Hospital), who underwent RMIP under local anesthesia over a 30-month period. Charts were reviewed for operative information, radiological and pathological diagnoses and post-operative course. The main outcome measures were the accuracy of localizing the parathyroid adenoma, operative time, achievement of normocalcemia post-operatively and perioperative morbidity.

RESULTS

Of the 55 patients we studied, 51 were cured as defined by normocalcemia following a single intervention, for an overall cure rate of approximately 93%. Four patients required an additional procedure: In two because of failure to remove a diseased gland, and in two because of multiglandular disease. The preoperative sestamibi scan accurately predicted the location of all abnormal parathyroid glands in 53 cases. In the remaining two cases, the scan failed to predict multiglandular disease. Average total operative time was 39 minutes. There were no major complications.

CONCLUSIONS

RMIP under local anesthesia is a safe and effective modality to treat primary hyperparathyroidism. The short operative time, the use of local anesthesia and the low complication rate make this technique a viable alternative.

Large remnant 131I ablation as an alternative to completion/total thyroidectomy in the treatment of well-differentiated thyroid cancer

BACKGROUND

An alternative to completion thyroidectomy for well-differentiated thyroid carcinoma is to ablate the remnant lobe with 131 I. The purpose of this study is to review our own experience with large remnant ablation.

METHODS

A retrospective review of 169 patients with well-differentiated thyroid cancer treated at one institution over a 14-year period was undertaken. Seventy-one patients who underwent partial thyroidectomy (PT) followed by 131 I ablation were identified. This group was compared to 98 patients treated with total thyroidectomy (TT).

RESULTS

Mean follow-up was 6.2 years for the 71 PT + 131 I versus 4.7 years for the 98 TT patients (P = .184). Recurrence occurred in 4 of 71 PT + I 131 patients (5.6%) versus 9 of 98 TT patients (9.2%) (P = .393). Other than a tendency for the size of the primary to be slightly larger and for the histology to be follicular carcinoma in the PT + 131 I patients, the 2 groups were nearly identical in age, gender, and other prognostic factors such as capsular invasion and metastases.

CONCLUSIONS

Large-dose ablation with 131 I is a viable alternative to completion thyroidectomy. Recurrence rates over an average 6-year period are similar to TT. Long-term monitoring of these cohorts is required.

The potential uses of high-dose-rate brachytherapy in patients with head and neck cancer

Brachytherapy has proven to be an extremely valuable method of treatment for head and neck cancer. The data supporting its application, however, is based on continuous low-dose-rate brachytherapy. To benefit from improved radiation protection, outpatient treatments, and increased patient tolerance of treatment set-up over that encountered in conventional low-dose-rate manually afterloaded brachytherapy, we implemented a high-dose-rate remote afterloading approach in selected patients with head and neck cancers. This treatment was utilized in two different roles in managing 29 patients. In its first role, it was used as the sole treatment in 13 patients with T1-2 N0 malignancies. A total of ten treatments of 450-500 cGy each were delivered twice a day with a minimum of 5-6 h between treatments. With a median follow-up of 9 months, only 1 patient failed locally. In a second role, brachytherapy was applied in a post-operative adjuvant setting following wide local excision of tumors in patients who presented with recurrent disease (12 cases) or a second primary in the head and neck (4 cases). All patients had previously received external irradiation to the head and neck. Due to this previous course of irradiation, only eight treatments of 300 cGy each were delivered, for a total of 2400 cGy over a period of 4 days. However, with a follow-up of 2-16 months, only 3 patients remain disease-free.

Impact of magnetic resonance imaging and computed tomography on the staging of laryngeal cancer

This retrospective study quantitatively assessed the effects of magnetic resonance imaging (MRI) and computed tomography (CT) on the staging of laryngeal cancer. A blind comparison between CT and MRI was made in a group of previously untreated patients with squamous cell carcinomas of the larynx. From June 1992 to November 1993, 29 patients were eligible for study. Of these, 14 patients (48%) had supraglottic lesions, 11 patients (40%) had glottic lesions and 4 patients (14%) had both. No subglottic lesions were seen. The data suggest that clinical staging of laryngeal tumors is inadequate. MRI proved superior to CT for staging tumors, especially those confined to the supraglottis. Nevertheless, clinically staged T1 or T2 lesions could be adequately assessed by CT alone. Findings also indicate that MRI should be reserved for T3 or T4 clinically staged lesions. Furthermore, most nodal disease can be staged by CT.