Minimally invasive surgery for primary hyperparathyroidism: a systematic review.

BACKGROUND: The aim of the present paper was to systematically review the literature regarding the safety and efficacy of minimally invasive parathyroidectomy techniques in patients with primary hyperparathyroidism. Studies using unilateral or endoscopic exploration following imaging were compared with bilateral open neck exploration. METHODS: Studies on minimally invasive parathyroid surgery were identified using MEDLINE (1984 to August 1998), EMBASE (1974 to August 1998) and Current Contents (1993 to week 34, 1998). The search terms were ((endoscop* or (minimal* and invasive) or unilateral) and parathyroid). The Cochrane Library was searched from 1966 to issue 3 1998, using the search terms 'parathyroidectomy or parathyroid resection'. Human studies of patients with primary hyperparathyroidism using unilateral or endoscopic exploration were included. Animal studies describing minimally invasive technique development were also included. A surgeon and researcher independently assessed the retrieved articles for their inclusion in the review. Studies directly comparing the unilateral method with bilateral open neck exploration were used to analyse outcomes. RESULTS: Analysis of data using odds ratios and 95% confidence intervals (CI) indicated a tendency to favour the unilateral technique. These individual studies generally had large CI, however; therefore preference to the unilateral procedure cannot be espoused with certainty. There is also a selection bias due to the strict enrollment criteria for unilateral surgery. CONCLUSIONS: The proposed role of minimally invasive parathyroid surgery is for patients with primary hyperparathyroidism who have unilateral parathyroid pathology. To assess the safety and efficacy of minimally invasive techniques it is suggested that their introduction be monitored as part of a trial in Australia, from which data should be accrued to a register.

Minimally invasive surgery for primary hyperparathyroidism: systematic review.

HYPOTHESIS: Use of minimally invasive parathyroidectomy techniques, either unilateral or endoscopic, will result in the same or improved safety and efficacy outcomes as those of the bilateral open neck exploration technique in patients with primary hyperparathyroidism. DATA SOURCES: Studies on minimally invasive parathyroid surgery were identified using MEDLINE (January 1984 to August 1998), EMBASE (January 1974 to August 1998), and Current Contents (week 1 of 1993 to week 34 of 1998). The search terms were as follows: ((endoscop* or (minimal* and invasive) or unilateral) and parathyroid). The Cochrane Library was searched from issue 1 of 1966 to issue 3 of 1998, using the search terms "parathyroidectomy or parathyroid resection." STUDY SELECTION: Human studies of patients with primary hyperparathyroidism using unilateral or endoscopic exploration were included. Animal studies describing minimally invasive technique development were also included. A surgeon (R.F.P.) and researcher (W.J.B.) independently assessed the retrieved articles for their inclusion in the review. DATA EXTRACTION: Studies directly comparing the unilateral method with bilateral open neck exploration were used to analyze outcomes. DATA SYNTHESIS: Analysis of data using odds ratios and 95% confidence intervals indicated a tendency to favor the unilateral technique. However, these individual studies generally had large confidence intervals; therefore, preference to the unilateral procedure cannot be espoused with certainty. There is also a selection bias due to the strict enrollment criteria for unilateral surgery. CONCLUSIONS: The proposed role of minimally invasive parathyroid surgery is for patients with primary hyperparathyroidism who have unilateral parathyroid pathological features. To assess the safety and efficacy of minimally invasive techniques, it is suggested that their introduction be monitored as part of a trial in Australia, from which data should be accrued to a register.

Clear parathyroid cysts and hyperparathyroidism.

There is reason to believe that clear parathyroid cysts are a separate pathologic entity distinct from degenerative cystic tumors of the parathyroid. They probably derive from enlargement of vestigial tubules or canals associated with parathyroid embryogenesis and they are rarely, if ever, hyperfunctioning. Indeed, if a clear parathyroid cyst is encountered in the clinical setting of primary hyperparathyroidism, then it is important to exclude a concomitant tumor in one of the other parathyroid gland, as in the case presented here. If the ionized serum calcium level is normal then clear parathyroid cysts can be diagnosed and treated definitively by percutaneous needle aspiration of their crystal clear fluid contents.

Adjuvant VHF therapy in locally recurrent and primary unresectable rectal cancer.

In a prospective randomized study, 434 mHz microwave therapy combined with external beam radiotherapy (VHF + RT) was compared with standard external beam radiotherapy (RT) in controlling locally recurrent or unresectable primary adenocarcinoma of the rectum. Independent assessors documented quality of life scores, performance status, toxicities, local response to treatment, and systemic disease progression before treatment and after treatment and every 8 weeks thereafter. Of 75 patients randomized, 73 were eligible for inclusion in the study. Forty-three of these patients had local pelvic tumour recurrence only and 21 also had distant metastases. In addition, nine patients had primary inoperable carcinomas, two of whom also had metastases. Thirty-seven patients were randomized to RT and 36 to VHF + RT. The median dose of radiation in the VHF+RT arm was 4275 cGy with a median fraction size of 150 cGy and median duration of therapy of 48.5 days versus 4500 cGy in the RT-only arm with a median fraction size of 180 cGy and median duration of therapy of 38 days. These doses are unlikely to be significantly different in biological effect. No significant difference between the two groups was observed in extent and duration of local control, measures of toxicity or quality of life scores. Additionally, survival and cumulative incidence of pelvic site of first progression did not differ significantly between the groups. We conclude that VHF microwave therapy in conjunction with radiotherapy produces no therapeutic advantage over conventional radiation therapy alone in the treatment of locally recurrent rectal carcinoma.

Surgically proven primary hyperparathyroidism with a suppressed intact parathyroid hormone.

A patient with hypercalcaemia had persistently suppressed serum intact parathyroid hormone levels (measured by immunochemiluminometric assay). However, other biochemical tests and open-neck exploration confirmed a diagnosis of primary hyperparathyroidism.

Study of intact (1-84) parathyroid hormone secretion in patients undergoing parathyroidectomy.

Patterns of intact (1-84) parathyroid hormone (intact PTH) elimination and subsequent recovery of parathyroid function were studied in 12 patients undergoing parathyroidectomy. Nine patients had primary hyperparathyroidism (HPT), with single gland disease in 6 and multiple gland disease in 3. Two patients had subtotal parathyroidectomy for HPT secondary to chronic renal failure and 1 underwent excision of a hyperfunctioning parathyroid autograft. Using a sensitive 2-site immunochemiluminometric assay, serum intact PTH levels were measured preoperatively, intraoperatively, and postoperatively. A dual phase pattern of hormone clearance was found in 10 of the 12 patients, including the patient undergoing autograft excision. A monoexponential clearance pattern was seen in the remaining 2 patients, both of whom had subtotal parathyroidectomies for multiple gland disease. In the patients with primary HPT due to single gland disease, the early phase of intact PTH clearance had a half-life (T1/2) of 3.3 (+/- standard deviation 0.9) minutes and a late T1/2 of 96.4 (+/- standard deviation 92.7) minutes. Calculation of decay curves and half-lives for the patients undergoing subtotal parathyroidectomy was more difficult because of the inherent uncertainty in determining time zero. Nevertheless, in all but 2 patients, the clearance pattern was biexponential and the T1/2 measurements were very similar to those encountered in patients with single-gland disease. In the 2 patients with monoexponential clearance, the T1/2 figures were 86.7 minutes and 26.7 minutes, respectively. In the patients undergoing parathyroidectomy for primary HPT, levels of intact PTH were lowest at 1-3 hours after surgery, recovering to normal in the majority of patients by 18-40 hours.

Mesenteric panniculitis resulting in bowel obstruction: response to steroids.

Two patients with mesenteric panniculitis are presented. The first developed obstruction of the sigmoid colon requiring a decompressing proximal sigmoid end-colostomy; the second presented with an incomplete small bowel obstruction. A convincing, immediate, symptomatic response to steroids was noted in both patients. The first patients responded to such an extent that closure of the colostomy was possible some 10 months later. It would appear that active subacute mesenteric panniculitis, as evidenced by continuing fever, high erythrocyte sedimentation rate and predominance of inflammatory cells with only minimal fibrosis on histologic section, is likely to respond favourably to steroid treatment. Review of the surgical literature indicates that, once the condition has progressed to established fibrosis, steroid treatment is probably ineffectual.

Demonstration of functioning heterotopic splenic autografts by scintigraphy.

The use of heterotopic splenic autografts is demonstrated as a means of preserving functioning splenic tissue in 15 patients undergoing splenectomy for trauma. In all patients, functioning splenic autografts could be shown by scintigraphy, using 99mTc-labelled erythrocytes or 99mTc-labelled sulphur colloid, performed 12 weeks after implantation.

Medical and surgical options in the management of patients with gastrinoma.

We reexamined our experience with the surgical and medical management of 53 patients with Zollinger-Ellison syndrome due to gastrinoma during the past decade. Surgical "cure" (defined here as resection of all identifiable tumor with normalization of serum gastrin and gastric secretory variables) appeared possible in 7 patients (of 44 explored, or 16%). Five of the 7 "cured" patients had duodenal wall tumors. Currently, these 7 receive no therapy, and none has apparent metastasis or multiple endocrine neoplasia, type 1. Excluding patients who have metastasis or multiple endocrine neoplasia, type 1 by preoperative screening would have increased the relative chance of surgical "cure" from 16% to 20% (7 of 35). Patients with unresectable or recurrent gastrinomas had a much worse prognosis than did patients whose tumors did not recur after resection or patients with a negative laparotomy. In any case, therapy with H2-receptor antagonists offered a satisfactory fallback position for management of gastric hypersecretion and its consequences. Adequate control by their use was achieved in 16 of 18 patients who were followed up an average of 28.9 mo (range 7-59 mo) without major side effects. Total gastrectomy, while undoubtedly the most effective therapy of gastric hypersecretion, is not free of significant sequelae, as evidenced by long-term follow-up of 18 gastrectomized patients. We concluded that (a) patients with Zollinger-Ellison syndrome without multiple endocrine neoplasia, type 1 or metastasis should undergo exploratory laparotomy and potential resection of identifiable gastrinomas, (b) chronic therapy with H2-receptor antagonists is preferable to total gastrectomy and satisfactory control may be achieved in most patients, and (c) tumor death is currently the major threat to survival for patients with unresectable gastrinomas, particularly nonmultiple endocrine neoplasia, type 1.

The reasons for persistent hypercalcaemia after cervical exploration for presumed primary hyperparathyroidism.

Of 500 consecutive patients who underwent cervical exploration for presumed primary hyperparathyroidism, 461 (92.2 per cent) were cured, as judged by an immediate return of serum calcium levels to normal. Thirty-nine patients (7.8 per cent) had persistent hypercalcaemia after the initial operation. The clinical profiles, operative and pathologic findings, surgical procedures performed and subsequent management of these 39 patients were reviewed. At reevaluation, 4 patients were noted to have been cured of their hyperparathyroidism. Twenty-one patients had persistent hyperparathyroidism: in 6, all 4 parathyroid glands had not been identified at the initial operation and in 15, hypercalcaemia persisted after the identification of 4 glands. One patient had recurrent hyperparathyroidism after the removal of a 720 mg adenoma and the identification of 3 normal parathyroid glands. Nine patients had nonparathyroid causes for the hypercalcaemia: 2 had occult malignant neoplasms, 6 had benign familial hypocalciuric hypercalcaemia and 1 had immobilization hypercalcaemia. In 4 patients the reason for the persistent hypercalcaemia remained unclear. We suggest a schema that may be used as a guideline in the investigation and management of patients with persistent hypercalcaemia after primary neck exploration for presumed hyperparathyroidism.

The surgical management of medullary thyroid carcinoma.

Medullary carcinoma of the thyroid may occur in three patient groups: multiple endocrine neoplasia, type 2b (MEN2b), MEN2a, and sporadic. The prognosis is best in MEN2a and worst in MEN2b. Multicentric disease occurs in approximately 90% of patients in the MEN groups and in 20% of the patients in the sporadic group. The minimal surgical procedure advocated is total thyroidectomy with dissection of the central compartment nodes. When neck dissection is performed, there appears to be no advantage in resecting the internal jugular vein or the sternomastoid muscle. Primary relatives of all patients with medullary carcinoma should be screened by measurement of plasma immunoreactive calcitonin to identify C-cell disease in a generally unsuspecting group/reservoir and because it results in earlier diagnosis, which leads to a less extensive surgical procedure and a higher percentage of patients with a disease-free state.

Adrenal surgery: trends during the seventies.

Surgical experience with adrenal disease from 1970 to 1979 was reviewed in 315 patients. The pathologic conditions that were encountered were hypercortisolism (74 patients), hyperaldosteronism (46 patients), adrenocortical carcinoma (35 patients), pheochromocytoma (77 patients), and nonfunctioning adenoma (47 patients). In addition, 5 patients with metastatic lesions, 14 with cysts, and 4 with myelolipoma were surgically treated. The accuracy of localizing adrenal lesions increased from about 50 percent to almost 100 percent during the decade studied. The increase was due mainly to the introduction of computerized tomography, the most important advance in the management of adrenal disease. The present study shows that adrenal surgery can be performed with low morbidity and mortality. Operative deaths were confined to patients with malignant disease or increased secretion of cortisol or catecholamines. Only patients with adrenocortical carcinoma (2 year survival probability, 34 percent) or hypercortisolism due to cortical hyperplasia (5 year survival probability, 76 percent) had significantly decreased survival.