Tomoyuki Yamashita

Surgical strategy for pheochromocytoma: Emphasis on the pledge of flank extraperitoneal approach in selected patients

BACKGROUND Anterior transabdominal exploration has traditionally been advocated as the standard procedure for pheochromocytoma. However, some authors claim that a flank extraperitoneal approach with accurate unilateral localization is justifiable. METHODS Retrospective analysis was performed on 87 patients with pheochromocytoma to determine the appropriateness of extraperitoneal exploration. RESULTS There were 45 men and 42 women with a mean age of 44.7 years (range, 16 to 83 years). Fifteen patients (17.5%) had pheochromocytoma as a part of multiple endocrine neoplasia (MEN) type 2A, and four had familial pheochromocytoma, von Hippel-Lindau disease, or von Recklinghausens disease. All tumors detected by preoperative localization studies were correctly identified and were resected through flank extraperitoneal (45 patients), transabdominal (28), thoracoabdominal (13), and posterior (1) approaches. Tumors were extraadrenal in 14, multiple in 22, bilateral in 12, and unequivocally malignant in 2 patients at the initial operation. Two patients died during the immediate postoperative period, giving an operative mortality of 2.3%. Two patients had persistent disease. During follow-up within a mean period of 5 years (range, 1 month to 13.7 years) 8 patients (9.1%) experienced recurrence or metastasis. Other than the patients with MEN 2, recurrence was not attributable to the operative approach. CONCLUSIONS If a preoperative localization study is accurate, an extraperitoneal approach is justifiable for many patients with pheochromocytomas.

Solid cell nests of the thyroid gland

The histogenesis and clinical significance of solid cell nests (SCN) of the thyroid are not fully understood. From August 1987 to December 1989 a total of 2544 patients with thyroid and parathyroid diseases underwent surgery at Ito Hospital, and SCN were revealed within the thyroid parenchyma in 21 (0.8%). Distribution of SCN was not limited to the upper one-third of the lateral lobe, and SCN were found even in the isthmus lobe. In 5 cases microcysts were also noted within SCN, and their content was thought to be acidic proteoglycan. Immunohistochemical study revealed that SCN were negative for thyroglobulin and calcitonin but positive for carcinoembryonic antigen. Thirteen of 21 cases showed positive immunostaining with cytokeratin. Scattered calcitonin-positive cells were noted around the SCN. It is suggested from these findings that SCN of the thyroid are closely related to certain cells of ultimobranchial body vestiges which may be not of neuroectodermal origin but of endodermal origin.

Mid-mediastinal parathyroid lesions: preoperative localization and surgical approach in two cases.

Although hyperfunctioning mediastinal parathyroid lesions that require median sternotomy or thoracotomy for removal are occasionally present, the majority are located in the anterior mediastinum closely associated with the thymus. Only eight cases of ectopic hyperfunctioning parathyroid tumors in the middle mediastinum have been reported. We experienced two cases of either persistent or recurrent hyperparathyroidism in which abnormal parathyroid tissue was located in the aorticopulmonary window. One of the patients had a parathyroid adenoma and the other had metastatic lesions of parathyroid carcinoma. In both cases, thallium scanning proved useful in identifying the lesions while computed tomography scan was effective for mediastinal three-dimensional localization. In one case, single photon emission computed tomography imaging with thallium proved beneficial for both identification and localization of the middle mediastinal lesion. The surgical approach used in both cases was different. In one case, left thoracotomy was performed, after which the ligamentum arteriosum was divided, and an adenoma anterior to the left main bronchus and posterior to the left pulmonary artery removed. In the other case, two metastatic tumors of parathyroid carcinoma anterior to the right main bronchus and posterior to the right pulmonary artery were resected through a median sternotomy and opening of the pericardium.

Pheochromocytomas: Tendency to Degenerate and Cause Paroxysmal Hypertension

Abstract. Eighty-four patients with pheochromocytoma underwent surgery during the 13-year period from 1981 to 1994. These patients were divided into three groups according to the degree of parenchymal degeneration, which was estimated by preoperative dynamic computed tomography (CT) scans and resected specimens: solid group, cystic group, and highly cystic group. The relation between the degree of parenchymal degeneration and the clinical variety, size of the tumor, predominant plasma catecholamine, and type of blood pressure disturbance was analyzed. There were 39 cases of solid pheochromocytoma, 37 cases of cystic tumor, and 8 cases of highly cystic pheochromocytoma. The maximal mean diameters for each group were as follows: 5.1 ± 2.3, 6.8 ± 3.0, and 7.9 ± 3.2 cm, respectively. Of the tumors < 3 cm in diameter, 84% were solid; when the tumors were ≥ 6 cm in diameter, approximately 50% were cystic and 20% highly cystic. Of the adrenal pheochromocytomas, 60% were degenerated; 79% of the extraadrenal tumors were solid. Of the epinephrine-secreting tumors, 70% were degenerated, and 55% of the norepinephrine-secreting tumors were solid. The clinical pattern of hypertension was related to the degree of degeneration: In the paroxysmal hypertension group 87% of the tumors were degenerated, and in the sustained hypertension group 69% were solid. We therefore believe that parenchymal degeneration of pheochromocytoma is highly correlated with the tumor diameter, location of the tumor, secreted catecholamine, and clinical pattern of hypertension.

Decision making using postoperative CEA and CA 15-3 for detection of breast cancer recurrence

To determine the clinical implications of postoperative levels of serum carcinoem-bryonic antigen (CEA) and CA 15-3 as follow up parameters for breast cancer, a retrospective study was conducted on 157 patients who underwent curative surgery for breast cancer. Twenty-three patients had recurrences and 134 patients were without recurrence for more than one year after measuring the tumor markers. The receiver operating characteristic (ROC) curves indicated that CA 15-3 performed more accurately than CEA in discriminating between patients with recurrence (n = 23) and those without (n=134). Of 23 patients with recurrence, CEA was elevated above the normal range (>2.9 ng/ml) in 32% and CA 15-3 was elevated above the normal range (> 20 U/ml) in 67%. The elevation of the markers preceded the clinical appearance of metastases in 2 patients for CEA and in 5 patients for CA 15-3. False positive rates for CEA and CA 15-3 in the 134 patients without recurrence were 4% and 10%, respectively. Nevertheless, these rates became 0% when the cut-off values were doubled. When the postoperative serum level of either CEA or CA 15-3 exceeds twice the upper limit of the normal range or when, in patients with unfavourable prognostic characteristics (node positive or large tumor), either of these values is between the upper limit of the normal range and double the value, recurrent breast cancer must be assumed. For such patients, further investigations with high-sensitivity radiographic modalities are warranted because early treatment may be able to provide survival benefit.