A Rare Case of Intrathoracic Malignant Goiter

Intrathoracic extension of the goitre is rare and occurs less often than retrosternal extension [1]. Anaplastic carcinoma is the least common type of malignancies amongst the primary tumours of  the  thyroid gland [2] and anaplastic carcinoma in the intrathoracic thyroid is extremely rare [3]. Anaplastic carcinoma of the thyroid gland is a rapidly growing cancer. At the time of diagnosis, anaplastic carcinoma of thyroid is usually not resect able  [4].  The  survival after diagnosis is few months [5]. While the  imaging  modalities, such  as  chest radiograph, thyroid scan, computed tomographic (CT) scan and magnetic resonance imaging (MRI)  may show extension into the chest or behind the sternum[6], these  modalities are unable to reliably determine  the resect ability of the goitre. Intrathoracic or retrosternal part of  a  benign or malignant goitre usually can be  resected  through cervical incision made for routine  thyroidectomy [7]. Occasionally, sternotomy is needed for difficult cases [8]. Rarely, operative technique may need to be modified even after sternotomy, for safe and complete removal and delivery of intrathoracic or retrosternal goitre. We present a case of a patient who presented with a large malignant goitre extending into the upper thorax and needed not only sternotomy but also additional surgical manoeuvre for complete and safe resection.

A 58-year male patient presented to the outpatient clinic with progressively increasing, painless swelling in front of the neck for 2 years. Seven months prior to presentation, patient developed hoarseness of voice, 3 months ago he developed dysphagia, and 2 months ago he developed dyspnoea and orthopnoea. Hoarseness, dysphagia, and dyspnoea worsened during the few weeks before presentation. There were no symptom of hyper or hypothyroidism. Patient’s social history was significant for 40-pack-years of smoking. His physical examination was normal except that he had a large, irregular anterior neck swelling measuring 10 x 14 cm in size. The swelling moved with deglutition but this mobility was markedly reduced. Swelling had smooth surface, was hard in consistency, non-tender, fixed to deep structures, with normal temperature of the overlying skin. Lower limit on right side of swelling was not reachable and neck veins were engorged. The patient became dyspnoeic and neck veins became prominent on elevating arms above his head (positive Pemberton’s sign). Trachea was shifted to the left. His carotid pulse was palpable but displaced posterolaterally (negative Berry’s sign). Lymph nodes were not palpable. The upper zone of the right chest was dull on percussion. His laboratory data showed normal complete blood count, electrolytes, and renal and thyroid functions with thyroid stimulating hormone (TSH) 2.02 mIU/L, T4 1.31 units and T3 100.6 ng/dL. Chest radiograph showed extension of thyroid into the chest with mass occupying upper one third of right chest cavity (Figure 1). A neck ultrasound showed large lobular well encapsulated thyroid mass measuring 68 x 52.8 mm and extending into the superior mediastinum compressing and displacing the trachea towards left. CT scan confirmed the presence of a large nodular mass involving right lobe of thyroid without cervical or mediastinal lymphadenopathy. Fine needle aspiration cytology had scant aspirate with degenerate atypical cells. Due to the patient’s clinical features and imaging findings, complete surgical excision of the thyroid gland was performed with help of cardiothoracic surgeon. A routine collar crease incision and Layhe’s technique was used to access the neck part of the thyroid gland and median sternotomy for the intrathoracic component. Intraoperatively, a large right lobe of the thyroid gland was noted which was extending into the right chest behind clavicle. The intrathoracic part was 2.5 to 3 times larger than the neck part and was compressed anteriorly by the subclavian vessels and posteriorly by ribs giving it a dumbbell shape. The mobilization and delivery of the thoracic part of the thyroid gland was not possible due to its large size and proximity to vessels. We performed a small vertical incision in the capsule above the subclavian vessels, debulked the thyroid gland while avoiding any spillage of its contents, and were able to deliver the thyroid gland into the neck safely. Bilateral thyroid lobectomies were performed after securing recurrent laryngeal nerves and parathyroid glands. Sternotomy and neck incisions were closed over drains after achieving haemostasis. Histopathological examination of the resected specimen showed well circumscribed spindle cell lesion with features of anaplasia including pleomorphic hyperchromatic nuclei and focal areas of necrosis. Benign thyroid follicles were seen at the periphery of the lesion. Cells were positive for vimentin but were negative for cytokeratin and epithelial membrane antigen; findings consistent with spindle cell type of anaplastic carcinoma of the thyroid gland. Patient’s postoperative course was uneventful and he was discharged home on 6th post-operative day. His hoarseness of voice had improved at 3-week follow-up visit.

Among all the primary  thyroid  carcinomas, anaplastic carcinoma is the least common [9]. Usually it is not resect able and the resection is possible only if it presents before extension to adjacent structures. The tumour grows rapidly and has short clinical history [5] .The larger the tumour size, lesser are the chances of it being resect able. Anaplastic  carcinoma may arise  in a normal or an abnormal gland [10]. Intrathoracic  extension of anaplastic carcinoma usually makes it inoperable [11]. The involvement of the vascular structures or airway makes the situation worse [12]. In this patient, the tumour was dumbbell shaped and the thoracic part was larger than the cervical part of the tumour. The right subclavian vessels anteriorly and rib posteriorly were compressing and straddling the tumour. For total thyroidectomy, either the tumour had to be divided at the point of compression by the vessels or division of rib. Both of these manoeuvres can make the operation difficult and time consuming. We opted for a different approach by making a small longitudinal incision in the cervical part of tumour and the bulk of the tumour was reduced from inside. Thus, tumour was able to be delivered in the neck and subsequently removed. Every precaution was taken to avoid the spillage and contact of tumour in the operative field. Anaplastic carcinoma is uncommon in intrathoracic goitres, however, the fact that such malignancies can grow considerably with no significant change in the patient’s symptoms argues for removal of all substernal goitres [13]. The preoperative diagnosis of thyroid carcinoma in intrathoracic goitre is difficult and often impossible [14]. A thyroid cancer in intrathoracic goitre has higher chance of being resected through a thoracic approach because of the need for surgical resection and the possibility of a greater extent of growth in the mediastinum [15]. The initial approach must be cervical, in any case, for a better control of the vascularization and to grant a complete removal of the cervical portion of the gland with no risk of damage of the recurrent laryngeal nerve. In most cases, the intrathoracic mass can be removed through a partial sternotomy, which is a simple enlargement of the cervical incision.  However, when the mass descends into the right posterior mediastinal space, a thoracotomy can become necessary for a safe and complete removal of the tumour [16]. Histologically, the intrathoracic forms are often anaplastic or rare. In conclusion, the anaplastic carcinoma can very rarely be intrathoracic and still be resect able. Even after sternotomy for removal   and   delivery of   thoracic part of gland, additional manoeuvres have to be performed for complete resection.

1. Rodrigues J,Furtado R, Ramani A, Mitta N, Kudchadkar S, Falari S. A rare instance of retrosternal goitre presenting with obstructive sleep apnoea in a middle-aged person. Int J Surg Case Rep. 2013;4(12):1064-6.
2. DeSantis CE,Lin CC, Mariotto AB, Siegel RL, Stein KD, Kramer JL, et al. Cancer treatment and survivorship statistics, 2014. CA Cancer J Clin. 2014 Jul-Aug;64(4):252-71
3. Chavan RN,Chikkala B, Biswas C, Biswas S, Sarkar DK. Primary Squamous Cell Carcinoma of Thyroid: A Rare Entity. Case Rep Pathol. 2015;2015:838079.
4. Cherkaoui GS,Guensi A, Taleb S, Idir MA, Touil N, Benmoussa R, et al. Poorly differentiated thyroid carcinoma: a retrospective clinicopathological  Pan Afr Med J. 2015 Jun 22;21:137.
5. Smallridge RC,Ain KB, Asa SL, Bible KC, Brierley JD, Burman KD, et al. American Thyroid Association guidelines for management of patients with anaplastic thyroid cancer.  2012 Nov;22(11):1104-39.
6. Shields T. General thoracic surgery. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2009.
7. Tsakiridis K, Visouli AN, Zarogoulidis P, et al. Resection of a giant bilateral retrovascular intrathoracic goiter causing severe upper airway obstruction, 2 years after subtotal thyroidectomy: a case report and review of the literature. Journal of Thoracic Disease. 2012;4(Suppl 1):41-48.
8. Coskun A,Yildirim M, Erkan N. Substernal goiter: when is a sternotomy required? Int Surg. 2014; 99(4):419-25.
9. Shaha AR. Anaplastic Thyroid Cancer: Large Database, Cautious Interpretations. Ann Surg Oncol.2015;22(13):4113-4.
10. Amacher AM,Goyal B,Lewis JS Jr, El-Mofty SK, Chernock RD. Prevalence of a hobnail pattern in papillary, poorly differentiated, and anaplastic thyroid carcinoma: a possible manifestation of high-grade  Am J Surg Pathol. 2015;39(2):260-5.
11. Regalbuto C,Frasca F,Pellegriti G, Malandrino P, Marturano I, Di Carlo I, et al. Update on thyroid cancer treatment. Future Oncol. 2012;8(10):1331-48.
12. Chernichenko N,Shaha AR. Role of tracheal resection in thyroid cancer. Curr Opin Oncol.2012;24(1):29-34.
13. AmericanThyroidAssociation (ATA) Guidelines Taskforce on Thyroid Nodules and Differentiated Thyroid Cancer, Cooper DS, Doherty GM, Haugen BR, Kloos RT, Lee SL, et al. Revised American Thyroid Associationmanagement guidelines for patients with thyroid nodules and differentiated thyroid cancer. Thyroid. 2009;19(11):1167-214.

14. Coskun A, Yildirim M, Erkan N. Substernal goiter: when is a sternotomy required? Inter Surg. 2014; 99(4):419-25.
15. Wang C, Sun P, Li J, Yang W, Yang J, Feng Z, Cao G, Lee S. Strategies of laparoscopic thyroidectomy for treatment of sub sternal goiter via areola approach. Surg Endosc. 2016:1-0.
16. Seong YW, Kang CH, Choi JW, Kim HS, Jeon JH, Park IK et al. Early clinical outcomes of robot-assisted surgery for anterior mediastinal mass: its superiority over a conventional sternotomy approach evaluated by propensity score matching. European Journal of Cardio-Thoracic Surgery. 2014;45(3):e68-73.