Posterior mediastinal goiter

PO~TE~OR USE OF COMBINED

~~~IASTI~A~

THORACOCERVICAL

GOITER”

APPROACH

WILLIAM C. VON DER LIETH, M.D. AND CHARLES W.

T

HE

Dallas, Texas

New

occurrence of posterior mediastinal goiter is infrequent. In previously reported cases various operative approaches were utilized for excision.‘-“0 The use of a combined thoracocervica1 approach for removal of a posterior mediastinal goiter is described herein. In Crile’sl series of I 1,800 thyroidectomies, there were ninety-seven intrathoracic goiters. In a series of 1,200 cases of goiter reported by Wakeley and I\;fulvany’ there were twenty intrathoracic goiters, of which only three were totalIy intrathoracic. The incidence of posterior mediastina1 goiter is still rarer. Only two in a series of 8,qoo cases of goiter were reported by Urban.” There are scattered reports of cases in the literature, but in aggregate there are fewer than forty. The usual location of intrathoracic goiter is in the anterior position of the superior mediastinum. An enlarging cervicai goiter can easiIy extend between continuous fascial pIanes into this substernal position, particuIarIy if the lower poIes enlarge. The mass derives its bIood supply from the inferior thyroid artery which descends with it. The recurrent Iarvngeal nerve lies posterioriy, as do the subclavian and innominate vessels. Diagnosis is usualiy not difIicuIt. These goiters, with rare exception, can be removed through a cervica1 approach, as Iong advocated by Iahey.” In rare instances the intrathoracic goiter lies posterioriy, either in the posterior portion of the superior mediastinum-cephaIad to the body of T4 or in the true posterior mediastinum, a division of the inferior mediastinum below the level of T4. Here the mass lies behind the subcIavian and innominate vesseIs and behind the recurrent laryngeal nerve and inferior thyroid vessels. The reason for posterior location is not clear. Sweet* believes that these goiters arise from the posterior aspect of the cervica1 thyroid

1953

LESTER,M.D.

York, New

York

rather than from the inferior poles and are thus directed toward the posterior mediastinum. A theory based on the embryology of the thyroid gIand has been described by Crohn and Kobak.E The main mass of the thyroid is dcrived from the ventra1 floor of the pharynx at the level of the first pharyngeal pouch (Arey). This primordium, forming the isthmus and a portion of each Iobe, is then joined by the uItimobranchia1 bodies, derived from the fifth pharyngeal pouches, giving rise to a major portion of each lobe. Failure of this fusion would leave the ultimobranchial bodies deep within the mediastinum, adjacent to the posterior pericardium--a source of thyroid tissue in the posterior mediastinum. Posterior mediastinal goiter cannot be as readily distinguished from other mediastinal tumors as can its anterior counterpart. This factor aIone has accounted for the utiIization of a thoracotomy in approaching the mass. Touroff has recentIy indicated that the use of radioactive iodine and a Geiger counter will revea1 functional thyroid tissue in the mediastinum in practically I00 per cent of cases. This will be an important aid to diagnosis. Symptoms due to compressive or compression distortion of the trachea and esophagus can be alleviated only by surgical excision of the goiter. In asymptomatic cases surgical removal is indicated as a prophylactic measure, as further growth is the usua1 course, with production of symptoms at a time when the surgical procedure is made more difficult by the larger size of the mass. Although the blood supply of a posterior mediastinal goiter usuaIly descends from the inferior thyroid artery, the routine USC of a cervical approach is not always feasibh. In the posterior mediastinum the mass of thyroid tissue may be.intimateIy adherent to the azygos vein or superior vena cava. Dissection around the mass performed bIind1.v from above would

* From the Roosevelt Hospital, New York, N. Y.

June,

FOR EXCISION

811

812

von der Lieth,

Lester-Posterior

certainIy have caused serious hemorrhage in the case reported herein. It must also be kept in mind that some of the bIood supply may be derived from mediastinal vessels. Another indication for transthoracic visualization is the inabiIity to distinguish definiteIy the goiter from other types of mediastina1 tumors. However, whiIe we beIieve that the cervical approach is frequentIy inadequate, we do not champion a pure thoracic approach in every case. ControI of the usua1 bIood suppIy, descending from the neck, may be diffIcuIt from within the chest because the vascuIar pedicle may be obscured by the overIying subcIavian vesseIs, as in this case. Thoracic exposure can be utiIized to identify the mass as a goiter, and to free it from the azygos vein and superior vena cava. Then, through a cervica1 incision, the bIood suppIy to the mass can be best secured, the mass safeIy drawn up out of the mediastinum and any associated cervica1 goiter can be removed. CASE

REPORT

M. Y., a sixty-five year oId white woman, was admitted to the GynecoIogy Service on January IO, 195 I, for investigation of postmenopausa1 vagina1 bIeeding. The patient had had two episodes of painIess bIeeding in the past four months. For severa years she had known of an enIargement in the Ieft side of her neck diagnosed as being in the thyroid, but with no recent change in size. Positive findings on physica examination, apart from the surgica1 condition, were obesity, paIpabIe enIargement of the Ieft lobe of the thyroid and a cystoceIe and rectoceIe. The Ieft Iobe and pyramida Iobe of the thyroid gIand were prominent and easiIy paIpabIe, estimated as two to three times normal size. The right Iobe was aIso paIpabIe but it did not present anteriorIy. Laboratory findings were as foIIows: hemo15.7 gm.; white bIood count, 9,050; gIobin Mazzini test, negative; urinalysis, unremarkabIe; fasting bIood sugars, 187, 172 mg. per 100 cc.; bIood urea nitrogen, 16.7 mg. per IOO cc. No radioactive iodine studies were carried out. X-ray examination of the IumbosacraI spine and peIvis reveaIed hypertrophic osteoarthritic changes. X-rays of the chest showed a soft tissue density in the right upper posterior mediastinum. The trachea was dispIaced an-

MediastinaI

Goiter

FIG. I. Postero-anterior roentgenogram of chest revealing mass in right superior mediastinum. teriorIy. With the esophagus outIined by barium, there was deviation to the left at the IeveI of the mass. FIuoroscopy revealed no puIsation of the mass. (Figs. I to 3,) DiIatation and curettage of the uterus reveaIed endometria1 hyperplasia and chronic cystic cervicitis. The patient was then transferred to the surgica1 service for investigation of the mediastina1 mass. AIthough there were no associated symptoms, surgica1 expIoration of the chest was advised because of the x-ray evidence of distortion of the trachea and esophagus which was beIieved wouId increase as the mass enIarged. Because of the possibiIity that this might be a tumor arising in the thorax, it was approached through the chest. At operation a parascapular incision was made and the chest entered through the bed of the fifth rib, after subperiostea1 resection of the fifth and a portion of the fourth ribs. A pear-shaped mass was found extending from the neck behind the subcIavian vesseIs into the posterior portion of the superior mediastinum, with the main buIk of the mass Iying to the right of the superior vena cava and with its base cIoseIy adherent to the azygos vein. It was covered by the parieta1 pIeura and its surface traversed by severa smaI1 veins. The mass had the appearance of thyroid tissue. The tumor was freed from the azygos vein and other mediastina1 structures by bIunt and sharp dissection. It became apparent that the principa1 bIood suppIy to the mass descended American

Journal

of Surgery

van der Lieth,

Lester--Posterior

2

FIG. 2. Anteroposterior roentgenogram left dcmonstratcd by barium swallow.

Goiter

Mediastind

3 of chest. Displacement

813

of esophagus to

Ftc;. 3. fright I;~tct:d view of chest; tr:tchca is disphtccd nntwiorly.

from the neck. Because it was not possible to transect the tongue of tissue safely as it descended lest the suhclavian vesseIs be injured, the chest waI1 was closed in the conventional manner. The patient was then placed in supine position and a cervica1 collar incision was made. The ribbon muscIes were divided to facihtate exposure of the thyroid gland. The left Iobe was three times enlarged and nodular in consistency. The pyramida Iobe was enlarged to twice the normal size and the right lobe projected posterioriy and inferiorly-, its lower pole being the previousIy exposed mediastina1 tumor. The upper poIe was wrapped around the trachea, with considerabIe tissue in the retrotracheal plane. The superior thyroid vessels were secured by suture ligatures, as was the group of middle thyroid veins. The inferior thyroid vessels were tied in continuity. In drawing up the mediastinal prolongation of the goiter, the clome of the pIeura was opened. This was later closed by interrupted sutures. We believed that the operation would be unnecessariIy prolonged by resection of the pyramidal lobe and a portion of the left Iobe of the thyroid, so closure of the cervica1 wound was accomplished to the emergence of a Penrose drain, which extended to the dome of the pleura. Silk technic was used throughout. Pathologic examination revealed the following: grossly, the specimen labeled right lobe of thyroid consisted of an irregular-shaped mass June,

1953

of thyroid tissue measuring 12 cm. in length, 3 cm. in greatest width and 2 cm. in greatest thickness. Its tota weight was 53 gm. It was made up of reddish tissue for the most part, with some areas of yellow tissue and a few areas of hemorrhage. Microscopically-, sections revealed salient features of so-caIIed fetal adenoma. Central areas were degenerated and small hemorrhages were present. The stroma was increased in some areas and a few cotlections of small lymphocytes were also seen. Diagnosis: nodular goiter; so-called fetal a denema. The patient toIerated the procedure well and made an uneventfu1 recovery. Her would healed per prinam. Postoperative x-rttys revealed full expansion of the Iung. She was fuI1.yambulatory Gthin forty-eight hours and was discharged on the eighth postoperative day. The patient has remained well. SUMMARY I. Posterior mediastinal goiter is discussed and one case is described. z. Cervical excision of all intrathoracic goiters is not always feasible. 3. The use of a combined thoracocervicaI approach is described and its advantages considered. REFERENCES I.

G., JR. Intrathoracic Quart., 6: 313, 1939.

CKILE,

goiter. Ckvetand

Clin.

von der Lieth,

Lester-Posterior

z. WAKELEY, C. P. G. and MULVANY, J. H. Intrathoracic goiter. Surg., Gynec. ti Obst., 70: 702, 1940. 3. URBAN, K. Beitrag zur retromediastinalen Struma. Cbirurg., II: 145, 1939. 4. SWEET, R. H. Intrathoracic goiter located in the posterior mediastinum. Surg., Gynec. # Obst., 89: 57, ‘949. 5. LAHEY, F. H. SurgicaI management of intrathoracic goiter. Surg., Gynec. I-Y Obst., 53: 346, 1931.

MediastinaI

Goiter

6. CROHN, N. N. and KOBAK, M. W. True posterior mediastinal goiter. Am. .I. Surg., 82: 283, 1951. 7. TOUROFF, A. S. W. Discussion. J. Tboracic Surg., 19: 741, 1950. 8. KEYNES, G. Thyroid surgery fifty years ago, with a contribution on intrathoracic goiter. &it. M. J., I: 621, 1950. g. MORA, J. M., ISSACS, H. J., SPENCER, S. H. and EIDIN, L. Posterior mediastinal goiter. Surg., Gynec. Ed Obst., 79: 314, 1944. IO. ELLIS, F. H., JR., GOOD, C. A. and SEYBOLD, W. D. Intrathoracic goiter. Ann. Surg., 135: 79, rg5z.

PATIENTS with peptic uIcer suffering a severe, acute, upper gastrointestina1 hemorrhage may first be tried on conservative therapy, especiaIIy if they are under fifty years of age. In eIderIy and arterioscIerotic patients prompt surgery is usuaIIy indicated because in an utter on the posterior duodenal waI1 or in the stomach the partiaIIy ruptured and scIerosed artery is not IikeIy to sea1 itself off. UIcers on the posterior duodenal waI1 may erode into the Iarge gastroduodena1 artery and, of course, the main arteries of the stomach are a11 large; hence prompt surgery is needed to prevent death. Even in younger patients if conservative therapy is ineffectua1 surgery must be performed. Blood transfusions are very heIpfu1; but if they cause the patient to bIeed more (by raising his bIood pressure), many surgeons discontinue preoperative transfusions until the bleeding has been controIIed on the operating table. UsuaIIy a subtotal gastrectomy is indicated in these instances. (Richard A. Leonardo, M.D.)

American

Journal

of Surgery