Detection of somatostatin receptors in surgical and percutaneous needle biopsy samples of carcinoids and islet cell carcinomas.

Somatostatin (SS) receptor status was investigated in the tumor tissues from 62 patients with carcinoid tumors and 15 patients with islet cell carcinomas using receptor autoradiography techniques with two different iodinated somatostatin analogues as radioligands, a [Leu8, DTrp22, Tyr25]somatostatin-28 and a somatostatin octapeptide, Tyr3-octreotide. The carcinoid tumors were either primaries (n = 32) or metastases (n = 43), sampled as surgical specimens or as small needle liver biopsies. Fifty-four of 62 carcinoid patients had SS receptor-positive tumors (87%). All 15 islet cell carcinoma patients had positive tumors (4 primaries, 11 metastases), i.e., 3 vipomas, 3 insulinomas, 2 glucagonomas, 1 gastrinoma, 2 polyfunctional tumors, and 4 nonfunctioning tumors. Saturation and competition experiments on tissue sections revealed saturable, high affinity binding sites pharmacologically specific for bioactive SS analogues. In a majority of the tumors, the receptors were densely distributed and were always homogeneously found in the whole tumor. All except two tumors were labeled with both radioligands. Multiple liver metastases (n = 16) from three different patients were all shown to contain a comparable amount of receptors. SS receptors could be demonstrated even in very small tissue samples of liver metastases obtained by percutaneous liver biopsies (mean weight, 6.8 mg). The majority of the eight SS receptor-negative carcinoids were mainly bronchial carcinoids (n = 5), usually poorly differentiated. On the contrary, SS receptor-positive cases were never found to be anaplastic. All tumors except one from patients pretreated with octreotide (3 days to 3.8 years) were SS receptor positive. In the majority of carcinoids or islet cell carcinomas, the SS receptor status correlated with the in vivo biochemical response (hormone inhibition) to octreotide. These data demonstrate (a) the high prevalence of SS receptors in the primary tumors of both carcinoids and islet cell carcinomas, (b) their presence in metastases as well, (c) their continuous expression even during long term octreotide therapy, (d) the possibility of measuring SS receptors in percutaneous needle liver biopsies, and (e) the evidence of their functionality. This study therefore suggests that tumoral SS receptors may be the likely molecular basis for octreotide action and may be an important parameter for predicting the therapeutic efficacy of SS analogues in carcinoids and islet cell carcinomas.

Arteriovenous fistula after biopsy of renal transplant: detection and monitoring with color flow and duplex ultrasonography.

An asymptomatic intrarenal arteriovenous fistula was incidentally discovered by color flow and duplex ultrasonography approximately 2 weeks after a percutaneous biopsy of a renal allograft. On the basis of information obtained from the color flow image and pulsed Doppler analysis, the vascular communication could be characterized without the need for angiographic correlation. The patient was managed successfully with close observation aided by serial ultrasound examinations. Spontaneous resolution of the fistula occurred within 4 weeks after the biopsy and was evident on a follow-up ultrasound examination. Duplex ultrasonography in conjunction with color flow imaging proved to be a valuable noninvasive technique for diagnosing and monitoring this postbiopsy vascular complication.

Persistent primary hyperparathyroidism: successful ultrasound-guided percutaneous ethanol ablation of an occult adenoma.

Ultrasound-guided percutaneous ethanol ablation of a small occult parathyroid adenoma was successfully performed in a patient with persistent primary hyperparathyroidism. This procedure may be an alternative to reoperation for patients in whom surgical treatment is contraindicated or who have an unacceptable risk of postoperative morbidity.

High-resolution ultrasonographic and pathologic abnormalities of germ cell tumors in patients with clinically normal testes.

Germ cell tumors that manifest as extragonadal masses in patients with testes that are normal to palpation are an unusual clinical finding. The possibility of the existence of an occult testicular primary tumor has prompted investigation of noninvasive techniques to examine the testes. The records of patients who had undergone high-resolution real-time ultrasonography of the testes were matched to those of patients who had presented with newly diagnosed germ cell tumors from January 1981 through October 1982. Six patients were identified, and their case records are reviewed. Ultrasonographic and pathologic findings are discussed. High-resolution ultrasonography seems to be an important adjuvant test in the assessment of patients with germ cell tumors who present with extragonadal disease.

Cystadenoma of the proximal common hepatic duct: the use of abdominal ultrasonography and transhepatic cholangiography in diagnosis.

Cystadenoma of the extrahepatic bile ducts is a rare cause of obstructive jaundice. In a case seen recently at our institution, the combined findings are abdominal ultrasonography and transhepatic cholangiography were diagnostic; such studies should provide evidence for preoperative recognition.

High-resolution parathyroid ultrasonography in familial benign hypercalcemia (familial hypocalciuric hypercalcemia).

Familial benign hypercalcemia, or familial hypocalciuric hypercalcemia (FHH), is frequently confused with primary hyperparathyroidism, but the consistent failure of subtotal parathyroidectomy to normalize serum calcium levels in FHH makes accurate distinction from familial hyperparathyroidism imperative. Because ultrasonography frequently demonstrates enlargement of the parathyroid glands in hyperparathyroidism, we examined 14 hypercalcemic adults (who had not undergone operation) from seven kindreds with FHH by using a high-resolution real-time scanner. We compared our results with those from 156 patients (who had undergone scanning preoperatively) with surgically confirmed hyperparathyroidism. Enlargement of the parathyroid glands was detected ultrasonographically in 137 of 156 (88%) of the total group of patients with hyperparathyroidism and in 17 of 24 patients (71%) with hyperparathyroidism who had hypercalcemia (serum calcium, 10.6 to 11.0 mg/dl) comparable to that of the FHH group (mean value, 10.7 mg/dl). In contrast, the single possible parathyroid lesion seen in the FHH group was substantially smaller (4 mm) than the smallest (7 mm, 75 mg) abnormal gland reliably detected by ultrasonography in the group with hyperparathyroidism and was conceivably normal in size. Patients with FHH have a dramatic absence of ultrasonographic parathyroid enlargement. High-resolution parathyroid ultrasonography may be of ancillary diagnostic benefit in patients with familial hypercalcemia.

High-resolution ultrasound-guided percutaneous needle biopsy and intraoperative ultrasonography of a cervical parathyroid adenoma in a patient with persistent hyperparathyroidism.

We present a case of persistent hyperparathyroidism in which high-resolution real-time ultrasonography was used to perform a percutaneous needle biopsy of a parathyroid tumor. Additionally, intraoperative ultrasonography was valuable in the precise localization of the tumor and thereby reduced the need for extensive surgical reexploration.

Endorectal ultrasonographic staging of rectal carcinoma.

Endorectal ultrasonography is a valuable imaging method for examination of the rectum and perirectal tissues. We assessed 50 patients with known rectal carcinoma prospectively by using a 7.0-MHz endorectal transducer to determine the depth of invasion of the rectal wall by tumor and the presence of lymphadenopathy. Tumors were staged by using the Astler-Coller modification of the Dukes staging system, and the results were compared with histologic staging of the surgical specimen. Ultrasonography had an accuracy of 80%, a sensitivity of 92%, and a specificity of 76% for detection of invasion of the perirectal fat. Ultrasonography was sensitive in the detection of perirectal lymphadenopathy but was not specific in distinguishing benign from malignant nodes.

Radiofrequency treatment of hepatic neoplasms in patients with permanent pacemakers.

Clinicians who provide care for patients with implantable devices for rhythm management, ie, pacemakers and internal cardioverter defibrillators, must be aware of sources of interference that could affect device function. Intracardiac radiofrequency is a recognized source of potential interference. However, radiofrequency to extracardiac sites that are relatively close to the implanted device has not been investigated thoroughly. We present 2 patients with permanent pacemakers undergoing intrahepatic radiofrequency for the treatment of metastatic disease. No interference was documented in either patient. Additional in vitro and in vivo studies are needed to determine definite clinical guidelines for such patients.

Occult functioning insulinomas: which localizing studies are indicated?

BACKGROUND: An occult insulinoma refers to a biochemically proven tumor with an anatomic site that remains indeterminate before operation. The amount of radiologic localization for such patients is debatable. METHODS: Sixty-five patients with sporadic insulinomas were surgically treated at the Mayo Clinic between January 1980 and December 1990. True occult tumors were present in 31% of these patients (n = 20). Thirty-eight negative preoperative localization studies were performed, with 10 patients undergoing more than one study. A benign adenoma was found in 19 patients when they underwent exploratory operation, whereas one patient had malignant disease with hepatic metastases. Thirteen patients underwent intraoperative ultrasonography with a 7.5 MHz real-time high-resolution transducer. RESULTS: Solitary lesions were successfully removed either by enucleation or by distal pancreatectomy in all 19 patients with benign disease. CONCLUSIONS: This high success rate in the management of occult insulinomas suggests that extensive preoperative radiologic investigation is neither indicated nor cost-effective.

Indications, technique, and efficacy of alcohol injection of enlarged parathyroid glands in patients with primary hyperparathyroidism.

BACKGROUND: Percutaneous alcohol ablation of the parathyroid gland (PAAP) has been proposed as an alternative treatment for primary hyperparathyroidism in patients unsuitable for surgery. The current study aimed to determine the (1) selection criteria, (2) associated morbidity, and (3) efficacy of PAAP. METHODS: From 1987 to 1998, 36 patients with primary hyperparathyroidism (mean age 65 years) underwent PAAP. The indications for PAAP were (1) medical comorbidity, (2) technically unsafe reoperative surgery, (3) partial ablation of a single remaining gland, and (4) patient choice. RESULTS: There were no long-term complications. Two patients had temporary recurrent laryngeal nerve injury and 4 had temporary hypocalcemia. Over a median follow-up of 16 months, 12 (33%) of the patients remained eucalcemic. For analysis purposes patients were separated into 2 separate groups: 29 with attempted complete ablation and 7 with partial ablation of a single remaining gland only. Ten of the complete ablation group (34%) remained eucalcemic. In the partial ablation group only 2 remained eucalcemic, but all had adequately controlled serum calcium levels. CONCLUSION: PAAP should be considered for hyperparathyroid patients with excessive reoperative morbidity or prohibitive medical comorbidity or those in whom the intent is to partially ablate a single remaining enlarged gland. In these patients close follow-up of serum calcium is required, and repeat treatments may be necessary because recurrence of hypercalcemia is likely.

Reoperative insulinomas, 1927 to 1992: an institutional experience.

BACKGROUND: Between 1927 and 1992, 313 patients have undergone surgery for insulinoma(s) at our institution, 12% of which were reoperations. We retrospectively reviewed all cases (n = 39) of reoperative surgery for persistent hyperinsulinism to identify changing patterns in surgical approach, morbidity, and outcome and to evaluate the influence of preoperative and intraoperative localization studies. METHODS: The diagnosis of endogenous hyperinsulinism has evolved from satisfying Whipple's triad to documenting concomitant hypoglycemia and endogenous hyperinsulinemia. Thirty-nine patients were divided into two groups for comparison: those treated before localization studies were available (1927 to 1967) (n = 17) and those treated since that time (n = 22). Initial operations were also compared with reoperations among these 39 patients. RESULTS: There were 26 women and 13 men (mean age, 42 years). There was at least one positive preoperative localization study in 16 of 22 patients (73%). Intraoperative ultrasonogram and careful palpation successfully identified 10 of 11 tumors in the reoperative setting. Blind or completion pancreatectomies were common before 1967 (10 of 17 patients). Since 1967, 14 of 22 patients have undergone enucleation of their primary tumor. Operative morbidity increased from 21% to 58% with reoperation but decreased from 65% to 29% (p = 0.026) when comparing the preangiography to the postangiography eras. The development of iatrogenic diabetes mellitus occurred in 13 patients (33%) after reoperation. Forty-one percent had diabetes before 1967 and 27% since that time (p = not significant). Thirty-four of 36 patients (94%) without malignant tumors were cured by reoperation. There was one operative death. Survival for patients who underwent completion or total pancreatectomy was significantly reduced (p = 0.003). CONCLUSIONS: Reoperations for persistent hyperinsulinism can be highly successful in experienced hands. These reoperations, however, are associated with increased morbidity and iatrogenic diabetes. With experience and the use of selected localization studies, first-time failures can be avoided in most cases thus reducing the need for reoperations and its inherent sequelae.

Jejunogastric intussusception.

Jejunogastric intussusception is a rare complication after gastric surgery. Only 16 documented cases have been reported at the Mayo Clinic, Rochester, Minn, during the past 72 years. Jejunogastric intussusception is a difficult condition to diagnose clinically. Essentially all patients have epigastric pain. Patients with intussusception generally have had retrocolic gastrojejunostomy without gastric resection. Intussusception of the efferent limb of jejunum is the most frequent type. Surgery is indicated for all patients with the acute type, whereas the chronic type may or may not require operative intervention, depending on the severity of the symptoms. Confirming the diagnosis at operation is occasionally difficult because of spontaneous reduction. Symptoms may recur after operation, but documented recurrence is rare.

Insulinoma. The value of intraoperative ultrasonography.

After establishing the diagnosis of an insulinoma, most surgeons prefer preoperative localization. Selective arteriography has long remained the gold standard for this purpose, but its use has been met with variable success. Despite various attempts at localization, insulinomas remain undetected in 10% to 20% of patients, and there may be a postoperative complication rate of at least 10% to 25%. To review the results and surgical implications of current localization techniques, 36 adult patients who were surgically treated for insulinomas at the Mayo Clinic, Rochester, Minn, from July 1982 through June 1987 were studied. The sensitivities of tumor localization using arteriography, computed tomography, and preoperative and intraoperative ultrasonography were 53%, 36%, 59%, and 90%, respectively. A subset of 29 patients underwent intraoperative ultrasonography, and all of these patients' insulinomas were identified with a combination of this technique and intraoperative palpation, with nonpalpable tumors being imaged in four patients. In 18 patients (62%), information obtained from the images appeared to influence the surgical management. While there is no substitute for exploration by an experienced surgeon, exploration appears to be enhanced by the addition of intraoperative ultrasonography, particularly during reoperation.

Magnetic resonance imaging of renal oncocytoma.

Two cases of renal oncocytoma studied by magnetic resonance imaging (MRI) suggest that this new imaging modality may prove useful in the preoperative diagnosis of oncocytoma and its differentiation from renal cell carcinoma.

Ultrasound-guided intervention: expanding horizons.

Ultrasound-guided intervention has enjoyed a period of unprecedented growth because its many advantages over other guidance modalities have been recognized. The decreased procedure time, increased accuracy, and safety of procedures performed under ultrasound guidance are of obvious benefit to radiologist and patient alike for all interventional applications. Lesions once considered unsafe to sample are now reasonably approached with ultrasound guidance. As equipment technology continues to improve and radiologists increasingly recognize the benefits of guiding procedures with ultrasound, the shift of procedures away from CT and fluoroscopic guidance will continue and ultrasound guidance will become the guidance method of choice for most interventional procedures.

Risk of parathyromatosis after fine-needle aspiration.

Reoperative surgery for hyperparathyroidism (HPT) is fraught with hazard. When preoperative imaging studies are inconclusive or patient comorbidities are extensive fine needle-aspiration (FNA) is helpful to confirm the presence of suspected parathyroid tissue in the neck. Some surgeons refrain from using FNA because of the concern of tissue implantation (parathyromatosis). A retrospective review (1984-1996) of all patients diagnosed with HPT undergoing FNA of suspected parathyroid tissue was performed to document whether a correlation exists between FNA of suspected parathyroid tissue and subsequent development of parathyromatosis. Parathyromatosis was considered to have occurred when proven by histology or suspected on the basis of clinical studies. Of 81 patients with HPT undergoing ultrasound-guided FNA to assess abnormalities in the neck 41 patients with confirmed parathyroid tissue were identified. The indications for FNA in these 41 patients were: prior failed cervical exploration (n = 33), prior neck surgery and/or radiation (n = 2), inconclusive noninvasive imaging studies (n = 15), and severe comorbidities (n = 8). Mean follow-up was 5.8 years. No case of FNA-induced parathyromatosis was identified. FNA is useful to confirm the presence of parathyroid tissue in very select patients with hyperparathyroidism. FNA often eliminates the need for other imaging studies, may prevent a needless or likely fruitless re-exploration, and does not cause parathyromatosis.

Intraoperative ultrasonography of the pancreas in children.

In children, lesions of the pancreas often are small, and precise localization is required for optimal surgical management. We have used newer-generation real-time ultrasonography of the pancreas intraoperatively in seven children. Five of these children had hypoglycemia, hyperinsulinemia, and insulinomas; one had a persistent small pancreatic pseudocyst with a disrupted secondary duct, and one had familial pancreatitis with a remarkably enlarged duct and a stone. Two of the five with adenomas had multiple endocrine neoplasia syndrome I (MEN I syndrome); in them, ultrasonography localized several adenomas preoperatively and several additional adenomas intraoperatively. This allowed a 90% pancreatectomy with enucleation of small adenomas in the remaining head. One child had a nonpalpable insulinoma deep in the head of the pancreas; intraoperative ultrasonography localized the lesion and permitted successful enucleation. Another child with a small pseudocyst and a disrupted secondary pancreatic duct ultimately required surgical drainage; intraoperative ultrasonography of the inflammatory mass immediately localized the small pseudocyst and thus decreased the operative time. The child with familial pancreatitis appeared to require a surgical drainage procedure; however, intraoperative ultrasonography demonstrated that the stone had passed spontaneously just prior to operation and the duct size had returned to normal, eliminating the need for the drainage procedure at that time.

Free-floating femoral vein thrombus in a patient with aspergillosis.

The management of a free-floating thrombus in the femoropopliteal or iliocaval veins is controversial. Such patients may have an increased risk of pulmonary embolism. The differential diagnosis of intraluminal venous malignancy or septic thrombosis must also be considered, especially in immunocompromised patients. This report reviews the management of a 56-year-old woman with bronchopulmonary aspergillosis who was found to have a free-floating thrombus in the femoral vein. Appropriate preoperative evaluation, emphasizing non-invasive studies and duplex exam, are discussed. In addition, the differential diagnosis, surgical options and perioperative care are considered. This patients represents a complex case of venous thrombosis in an immunocompromised patient and, therefore, the optimal care to minimize complications, such as pulmonary embolism, and prevent recurrence or post-thrombotic changes, is necessary.

Ultrasound-guided biopsy and ablation in the neck.

Management and therapy of conditions of the thyroid, parathyroid glands, and cervical lymph nodes have evolved rapidly during the past 15 years. The development and continued improvement of high-resolution ultrasound (US) equipment, US-guided biopsy, and image-guided ablative techniques have fueled this change. These technical improvements and the knowledge and experience gained during this time have decreased the rate of unnecessary surgery in patients with thyroid nodules. They have also allowed more limited neck dissection in patients with parathyroid adenomas and have led to the development of US-guided ablative techniques that have eliminated the need for surgery in some cases. This article reviews the rationale and techniques of US-guided biopsy of the thyroid, parathyroid, and cervical lymph nodes. Established and evolving ablative techniques of these structures are also examined.