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CASE REPORT
Year : 2021  |  Volume : 24  |  Issue : 11  |  Page : 1749-1754

Management of a huge intrathoracic goitre in a rural specialist hospital in Nigeria–Case report and review of literature


1 Department of Surgery, General Surgery Unit, Irrua, Edo State, Nigeria
2 Cardiothoracic Surgery Unit, Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria
3 Department of Anaesthesia, Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria

Date of Submission02-Mar-2021
Date of Acceptance24-May-2021
Date of Web Publication15-Nov-2021

Correspondence Address:
Dr. A A Okomayin
Consultant General Surgeon, ISTH, Irrua, Edo State
Nigeria
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/njcp.njcp_101_21

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   Abstract 


Retrosternal goiter is expectedly a common presentation in rural African communities due to long periods of neglect. The treatment of choice is surgical – commonly via a trans-cervical incision. A few require an extra-cervical surgical approach and multidisciplinary management as reported in this case performed in a rural specialist hospital in Nigeria.

Keywords: Goitre, intrathoracic, retrosternal, sternotomy


How to cite this article:
Okomayin A A, Dongo A, Tagar E, Odion C, Akerele M, Omosofe F. Management of a huge intrathoracic goitre in a rural specialist hospital in Nigeria–Case report and review of literature. Niger J Clin Pract 2021;24:1749-54

How to cite this URL:
Okomayin A A, Dongo A, Tagar E, Odion C, Akerele M, Omosofe F. Management of a huge intrathoracic goitre in a rural specialist hospital in Nigeria–Case report and review of literature. Niger J Clin Pract [serial online] 2021 [cited 2021 Nov 28];24:1749-54. Available from: https://www.njcponline.com/text.asp?2021/24/11/1749/330454




   Introduction Top


Retrosternal goiter (RSG) refers to goiters that extend beyond the neck or arise from embryonic remnant thyroid tissues in the thorax.[1],[2] A “true intrathoracic goiter” is completely retrosternal with no connection to the cervical thyroid gland. Some actually have a thin connecting pedicle that is unrecognized.[3] The management of RSG with a huge intrathoracic component requires, in addition, the performance of a sternotomy/thoracotomy and perhaps a collaboration with the thoracic surgeons.[3],[4] This can be a great challenge in a rural hospital setting. We report this case as the first sternotomy done in our rural specialist hospital for intrathoracic goiter and review the literature on retrosternal/intrathoracic goiters.


   Case Presentation Top


A 55-year-old woman was referred to our rural specialist hospital with a neck swelling of 10 years. She had effort intolerance, snores at night but had no dyspnea, dysphagia, or voice change. There were no suggestive symptoms of hypothyroidism, hyperthyroidism, or malignancy. She has had two previous surgeries (ORIF of right tibial and myomectomy). She was not known to be hypertensive or diabetic and no known drug allergies. She was anxious and overweight (BMI 29.4 Kg/m2), pulse 96/min, BP 150/80 mm Hg, RR 20/min, Temp. 37°C, and normal jugular venous pressure (JVP). She has a short neck and a huge anterior neck mass consistent with goiter, 6 × 8 cm, firm, multinodular with retrosternal extension. Her trachea deviated to the right, and her chest findings were normal.

Laboratory reports showed normal hemogram, electrolytes, urea, creatinine, serum calcium, phosphate, and thyroid function test. Thyroid USS revealed enlarged right, left thyroid gland and isthmus with multiple nodules and cystic changes, devoid of calcifications. X-rays showed radio-opaque superior mediastinal shadow extending superiorly into the neck, trachea deviation to the right, and hypertensive cardiovascular changes (CTR of 56.8%). CT scan showed a mass in the neck with extension to the anterior mediastinum [Figure 1], [Figure 2], [Figure 3]. ECG revealed leftward axis and possible left bundle branch block. ECHO suggested systolic and diastolic dysfunction. Fine needle aspiration technology (FNAC) reported benign lesions, and an indirect laryngoscopy showed a normal internal laryngeal framework. COVID-19 test (a preoperative protocol adopted during the heat of the COVID-19 pandemic) was negative.
Figure 1: Coronal cervicothoracic CT view of the goiter

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Figure 2: Axial cervical CT view of the goiter (arrow indicating the trachea deviated to right)

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Figure 3: Axial thoracic CT view of the huge intrathoracic component

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She was counseled for surgery and associated risks, including a detailed plan for median sternotomy and postoperative recovery in ICU. The cardiologist and thoracic surgeons were consulted for expert opinions with regards to the planned procedure.

She had total thyroidectomy via a cervical collar incision and a median sternotomy [Figure 4] and [Figure 5]. Sternotomy was performed with Lebsche sternotomy knife/chisel and mallet; hemostasis secured with cautery and bone wax. The padded sternal edges were retracted with Finnocheto self-retaining retractor. The cervical goiter supplied by the thyroid arteries weighed 257 g and was connected to the mediastinal portion (weighing 286 g) by fibrous tissue. Blood supplies to the latter were from intrathoracic vessels. A drain was left in the retrosternal space, and the sternum reapproximated with 6 interrupted stainless steel wires knitted at equal distance from each other. Surgical wounds were closed in layers. Her vocal cords were mobile at extubation, and she was transferred to ICU for closer monitoring.
Figure 4: Intraoperative view of the thoracic component with Finnocheto retractor in place

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Figure 5: Specimens removed (arrow indicates the thoracic component)

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The wound drain was removed on the 2nd postoperative day. Postoperative serum calcium dropped by 1 mg. She had supplemental calcium tablets and a replacement dose of L-thyroxine (100 μg PO daily). CXR done on the 3rd postoperative day showed cardiomegaly (CTR 67.7%) and bilateral hilar fullness with upper lobe vascular diversion. The cardiologist added low-dose spironolactone and ramipril before she was discharged. Microscopic histology of the cervical and thoracic masses revealed the nodular arrangement of variable-sized follicles lined by cuboidal epithelium containing colloid consistent with goiter [Figure 6]. Her clinic follow-up has been uneventful, and she has been very cheerful [Figure 7].
Figure 6: Photomicrograph showing a nodular arrangement of variable size follicles lined by cuboidal epithelium containing colloids with attendant foamy macrophages (H&E ×40)

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Figure 7: Postoperative picture taken 3 months after surgery

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   Discussion Top


Lahey and Swinton described the neck as a “space with no bottom.”[4],[5] This anatomical confinement makes an enlarging thyroid gland (goiter) descend down into the thoracic cavity, aided by gravity and the negative intrathoracic pressure during swallowing and respiration. This situation is described with several terminologies – retrosternal, substernal, cervicothoracic, intrathoracic, endothoracic, or mediastinal goiter.[1],[2],[3],[4],[5]

Literally, any goiter whose inferior pole descends beyond the manubrosternal notch is referred to as RSG. Clinically, a portion of this goiter remains permanently below the sternal notch, and is impossible to palpate the lower pole of the mass.[3],[6] There is no consensus on the extent of descent in the thoracic cage. Various cut-off points suggested include >3 cm, 2-fingerbreadths below the notch, level of the 4th thoracic vertebra (Lindskog and Goldenberg), aortic arch (Crile), carina trachea, etc.[2],[7],[8] Katlic's definition is most commonly quoted and is most useful in predicting the need for a sternotomy. He defined RSG as one that has its greater mass (i.e., >50% of its mass/size/volume) inferior to the thoracic inlet.[2]

The description above refers to only one category of RSGs. A second category exists, though rare, where the goiter is completely retrosternal (”true” intrathoracic) with no connection or a fibrous connection to the cervical thyroid gland. Such primary RSG is taught to develop from ectopic thyroid tissues which can be located anywhere between the neck and the diaphragm.[8],[9] Unlike the more common secondary RSGs with blood supply from cervical branches of the thyroid arteries, the blood supply to the primary RSGs are from intrathoracic/mediastinal sources such as the aorta, subclavian artery, internal mammary arteries, thyrocervical trunk, or innominate artery.[2],[4],[6] The reported case had a fibrous connection to the cervical goiter with blood supply both from cervical and intrathoracic arteries.

RSGs share a number of properties with their cervical counterparts (etiology, pathology and growth rate, age and sex distribution, symptomatology, treatment, and prognosis).[2] Reported incidences vary from 1% to 20% owing to nonuniformity in the definition.[3],[7],[10],[11] A vast majority is found in the anterior mediastinum (its natural path of descent) and 10%–15% in the posterior mediastinum.[3],[4],[9],[12] Typically, the descent is to one side with a contralateral displacement of the trachea as was seen in the index case [Figure 2]. The descent may also be on both sides. Many have reported equal incidence of left and right retrosternal extensions, whereas some noted right-sided predominance with some goiters arising from the left thyroid lobe growing into the right mediastinum due to the presence of the aortic arch on the left.[2],[13]

RSGs can grow to considerable sizes without any marked clinical manifestation and 20%–40% of cases are asymptomatic.[3],[4],[8] Common symptoms are dyspnea, sleep disturbance, stridor, dysphagia, change in voice (dysphonia), cough, wheeze, and choking sensation.[2],[3],[14],[15] These symptoms may be positional (occurring only when the patient lies supine or their arms are raised or their neck extended or when they look to one side) as the mass is being drawn into the thoracic inlet.[16] Dilated veins and facial flushing suggest superior vena cava obstruction.[17] Mechanical compressive effects are more marked in RSGs compared with their cervical counterparts and sometimes may threaten the patient's life.[2] Our patient did not experience most of these symptoms described and this may be due to the thin connection between the cervical goiter and intrathoracic goiter.

Benign RSGs can be associated with a euthyroid, hypothyroid, hyperthyroid state.[18],[19] Malignancy is reported in 3%–21% of cases[6],[20] The potential for bleeding, consequent airway embarrassment, and high rate of missed biopsy make needle biopsy a risky venture – a rationale for surgical removal adopted by most surgeons.[2] CXR may be normal or show mediastinal radio-opaque shadow deviating or compressing the trachea with an untraceable superior margin of radio-opacity – traceable on thoracic inlet X-ray.[19],[21] Neck USS suggests RSG when it is unable to delineate the inferior part of the goiter posterior to the sternum, but it often fails to provide detailed information about the RSG.[19] Although CT scan for RSGs is not routine in our rural hospitals, it was prompted by the finding of a mediastinal radio-opaque shadow on CXR. CT/MRI is most helpful in delineating the entire mass and its relationship to adjacent structures (trachea, esophagus, great vessels) and most reliable in predicting the need for sternotomy.[3],[7],[19],[20] Following surgery, the resected goiter is compared with CT imaging to minimize the risk of a “mediastinal remnant” (also called “forgotten goiter”).[7]

Surgery for patients with RSG is strongly indicated because of the potential risk of compressive symptoms, the possibility of thyroid malignancy, and the ineffectiveness of nonoperative treatments.[3],[6],[9],[20],[22] L-thyroxine, I131, and radiotherapy are reserved only for patients with exceptionally high operative risk or who refuse surgery.[2] Most surgeries are performed successfully using the transcervical approach.[23],[24] An experienced surgeon should anticipate operative challenges such as difficult intubation, uncontrollable hemorrhage, injury to the recurrent laryngeal nerve, and incomplete removal of the gland.[3] Where sternotomy or thoracotomy is indicated, proper counseling of the patient and consultation with the endocrine, cardiac/thoracic surgeons improve the patient's safety and surgical outcome.[4],[6] Such consultation and collaboration were instrumental to the successful outcome of our case.

The most important factor to predict whether an RSG can safely be removed trans cervically is believed to be the presence of a clear tissue plane around the mass,[3],[4],[11] and a key limiting step in the transcervical approach is the delivery/dislocation of the mediastinal component of the goiter into the neck.[7] Subcapsular dissection, digital blind sweeping motion, and traction (using sponge holding clamp, heavy silk sutures, and Foley catheter) were among several methods used to mobilize the retrosternal components of the goiters.[2],[4],[5] Kocher,[25] in his work had recognized hemorrhage as a major operative problem of RSGs and recommended double ligation of all accessible vessels from above. He also designed special forceps and a spoon for delivering the goiter and advised fragmentation/morcellation technique, which was later popularized by Lahey.[23] Although these techniques may be successful, adding thoracic access is prudent practice and could avoid excessive bleeding and theoretical disadvantages of an occult malignancy.[20]

Among skilled head and neck or endocrine surgeons, the percentage of RSGs that require an extra cervical approach is 2%–5%.[8] Sternotomy is recommended when the mediastinal part is wider than the thoracic inlet (e.g. iceberg-shaped goiters) or when >70% is retrosternal or the goitrous mass in the thorax is >10 cm. Other indications include an extension of the goiter to the aortic arch or the carina trachea, revision surgery for recurrent RSG, remnant mediastinal goiters, previous radiotherapy, malignancy with local invasion, goiter adherent to surrounding mediastinal tissues, completely intrathoracic goiter, superior vena cava syndrome, emergent trachea compression and when the goiter cannot be extracted from the chest with gentle sweeping maneuvers and traction.[8],[14],[21],[26],[27] In one study, researchers from Leeds Teaching Hospital classified RSGs based on anatomical locations, shapes/sizes on neck/thoracic CT.[7] This classification is very useful in determining the surgical approach preoperatively as shown in the table below [Table 1]. Six (6) of the 98 RSGs in their study were similar to the case we reported. One (1) out of 26 RSGs of 537 thyroidectomies required sternotomy in a study performed by Khairy et al.[19] The goiter extended down to the level of the pulmonary trunk. In another study, sternotomy was required in 4 cases of 42 substernal goiters operated.[3]
Table 1: Classification of retrosternal goitres based on anatomical location and shape on CT Scan

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Surgeons in a rural setting especially in resource constraint nations must anticipate all challenges posed by the retrosternal descent of goitres. Majority of patients with RSGs are intubated successfully under direct laryngoscopy without any difficulty.[28],[29],[30] Difficult airways may require the use of a tracheal tube introducer (bougie), video laryngoscope and fiberoptic bronchoscope-assisted tracheal intubation.[29] The latter was used for our patient as difficulty with her intubation was presumed due to her short neck and trachea deviation to the right. Rigid bronchoscopy and tracheostomy remain part of an airway management plan for those with respiratory distress from tracheal compression.[31]

In modern practice, sternotomy is performed by an oscillating sternal saw (electric or pneumatic powered). In its absence, we used a Lebsche knife/chisel consisting of a T-shaped rod, a knife at its distal shaft and a gouged tip. An oscillating sternal saw is safer and easier to use than the Lebsche knife. With a partial or total sternal split as was done for the index patient, it is easier to mobilize the thoracic part of a RSG and secure haemostasis. The wider operative access provided by sternotomy enables the surgeon to tie intrathoracic/mediastinal vessels and aberrant blood supplies to the gland. It also reduces the incidences of fragmentation of the gland during its mobilization using the traditional transcervical approach popularized by Theodore Kocher and Lahey.[20],[23],[24],[25] In addition, it reduces the chance of leaving remnant thyroid tissues behind – a phenomenon that is comparatively more common with the transcervical approach and is regrettable if malignancy is diagnosed.[20]

The removal of a RSG is more challenging and present a slightly higher risk of bleeding than a cervical goitre.[8],[25] Meticulous dissection and good haemostasis during thyroid surgeries help to reduce the incidence of associated morbidities such as inadvertent injuries to the recurrent laryngeal nerve and parathyroids, tension hematoma and infection. Haemostatic surgical clips, energy devices (such as harmonic scalpel and LigaSure) and topical haemostatic agents (e.g. fibrin sealant, Tiseel, FloSeal, Surgicel) are useful adjuncts to good surgical techniques during thyroidectomies.[32] They also reduce operating time compared to the traditional “clamp-and-tie” technique used for the patient in this case report.

It is advised that a RSG be managed by skilled surgeons familiar with its unique pitfalls and challenges.[8] The surgeon must take advantage of all available surgical devices, consultations and collaboration. This multidisciplinary approach to patient care was used for the patient in this case report and it involved the general surgeons, anaesthetists, a cardiothoracic resident, a critical care physician and a cardiologist. This no doubt contributed immensely to the overall outcome.


   Conclusion Top


Though rare, some RSGs require extracervical surgical approaches and multidisciplinary care. Surgeons in rural settings must recognize these challenging cases by thorough preoperative evaluation and institute appropriate measures for optimal surgical outcome.

Declaration of patient consent

The authors certify that they have obtained the appropriate patient consent form. In the form, the patient gave her consent for her images and other clinical information to be reported in the journal. The patient understands that her name and initials will not be published and due effort will be made to conceal her identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

None.

Conflicts of interest

There are no conflicts of interest.



 
   References Top

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De Andrade MA. A review of 128 cases of posterior mediastinal goiter. World J Surg 1977;1:789-97.  Back to cited text no. 13
    
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De Perrot M, Fadel E, Mercier O, Farhamand P, Fabre D, Mussot S, et al. Surgical management of mediastinal goiters: When is a sternotomy required? J Thorac Cardiovasc Surg 2007;55:39-43.  Back to cited text no. 14
    
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Bizakis J, Karatzanis A, Hajiioannou J, Bourolias C, Maganas E, Spanakis E, et al. Diagnosis and management of substernal goiter at the University of Crete. Surg Today 2008;38:99-103.  Back to cited text no. 15
    
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Tunc M, Sazak H, Karlilar B, Ulus F, Tastepe I. Coexistence of obstructive sleep apnea and superior vena cava syndromes due to substernal goitre in a patient with respiratory failure: A case report. Iran Red Crescent Med J 2015;17:e18342.  Back to cited text no. 17
    
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Lin Y-S, Wu H-Y, Lee C-W, Hsu C-C, Chao T-C, Yu M-C. Surgical management of substernal goitres at a tertiary referral centre: A retrospective cohort study of 2,104 patients. Int J Surg 2016;27:46-52.  Back to cited text no. 18
    
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Cichoń S, Anielski R, Konturek A, Baczyński M, Cichoń W, Orlicki P. Surgical management of mediastinal goiter: Risk factors for sternotomy. Langenbecks Arch Surg 2008;393:751-7.  Back to cited text no. 22
    
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25.
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    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7]
 
 
    Tables

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