New genetic causes of pheochromocytoma: current concepts and the clinical relevance

Pheochromocytoma and paraganglioma are tumors of the autonomous nervous system mainly occurring in the adrenal medulla, but also in the extraadrenal paraganglias of the abdomen, thorax, neck and skull basis. The etiology comprises germline mutations of now 6 genes. About 10 years known are the RET gene susceptible for multiple endocrine neoplasia type 2, the VHL gene for von Hippel-Lindau Disease, and the NF 1 gene for neurofibromatosis Recklinghausen (neuro- fibromatosis type 1). Since 2000 the genes for succinatedehydrogenase subunits SDHB, SDHC, and SDHD have been identified for paraganglioma syndromes type 4, type 3, and type 1 respectively. Investigations of series of pheochromocytoma patients identified germline mutations in one of the genes SDHB, SDHD, VHL and RET in 24% to 50% of the patients. Multifocal tumors, young age and positive family history, known features associated with inheritence, have not been present in all patients. Therefore, analyses of blood DNA for mutations in these genes are recommended. Positive tests provide the patients and their relatives with essential platforms for clinical care. Experiences in this field of medicine have shown that optimal management of patients with pheochromocytoma-associated syndromes is a high challenge. National registries may be instrumental in order to provide with adequate facilities.

Glucocorticoid-induced osteoporosis

Glucocorticoids are important drugs in the treatment of variety diseases, but long-term period use can lead to various adverse effects, including osteoporosis. Glucocorticoid-induced osteoporosis is mainly caused by inhibition of osteoblastic bone formation, which results not only in decreased bone mineral density, but reduction of bone strength by trabecular thinning in bone microstructures. The evidence suggests that daily oral glucocorticoid doses higher than 5 mg prednisolone or equivalent increase the risk of fracture within 3-6 months after the start of therapy. High-dose inhaled glucocorticoids may also increase fracture risk. The diagnostic procedures are similar to those for primary osteoporosis, but the diagnostic threshold for bone mineral density needs to be higher than that for primary osteoporosis. Treatment with vitamin D, calcitonin, sex hormone replacement, and bisphosphonates has been shown to be effective, and bisphosphonates have been demonstrated to be the most valuable drugs for glucocorticoid-induced osteoporosis. There are several lines of evidence indicating that they are effective in preventing and treating low bone mineral density and in reducing fracture risk.

RET oncogene mutations in 75 cases of familial medullary thyroid carcinoma in Japan

The familial form of medullary thyroid carcinoma (MTC) is caused by mutations of the RET protooncogene. We registered 60 multiple endocrine neoplasia (MEN) 2A patients, 12 familial non-MEN medullary carcinoma (FMTC) patients, and three MEN2B patients with a confirmed RET germline mutation. All 60 MEN2A patients had RET mutations in a cysteine-rich domain. Seven of the FMTC patients had a mutation in cysteine-rich domain, and the other five had a mutation in codon 768, which encodes a tyrosine-kinase domain. Two of the MEN2B patients had a mutation in codon 918, and one patient had a double mutation, one in codon 804 and the other in codon 806, both of which are all encoded tyrosine-kinase domain. The genotype-phenotype correlations of our data will allow individualized recommendations for the optimal timing of prophylactic surgery.

Proposal for the histological classification of parathyroid carcinoma

Although the criteria of Schantz and Castleman are widely used in the diagnosis of parathyroid carcinoma, many tumors diagnosed as carcinoma subsequently do not recur. In addition, although Bondeson's criteria are used to grade parathyroid carcinoma, instances of patient mortality have been documented even in cases where the histological features did not conform to the criteria for high grade. Considering our experience, we believe that the subclassification of parathyroid carcinomas defining tumors limited local infiltration as low-grade and those with widespread infiltration as high-grade may be useful.

Case of Infectious Endocarditis Predicted by Orbital Color Doppler Imaging

BACKGROUND

There are no specific ocular findings for infectious endocarditis. We report a case of infectious endocarditis detected by combining orbital color Doppler imaging (CDI) and ophthalmological findings.

CASE

A 47-year-old man suffered from lumbar pain and low-grade fever. He had undergone heart surgery for a ventricular septal defect and received blood transfusions 20 years earlier, and he had started interferon therapy for chronic hepatitis C 8 months previously. Systemic examinations suggested either collagen disease, malignant lymphoma, or infectious disease.

OBSERVATIONS

The patient underwent a complete ophthalmological examination, including CDI. Ophthalmoscopy showed multiple cotton-wool patches in both eyes and branch retinal artery occlusion in the left eye. Orbital CDI showed that bilateral ophthalmic arteries and central retinal arteries flowed synchronously with abnormal waves composed of three narrow, sharp peaks. These findings were suggestive of a cardiac valve disorder, which can lead to embolisms. Echocardiography established the diagnosis of infectious endocarditis.

CONCLUSIONS

To the best of our knowledge, this is the first reported case of infectious endocarditis detected by orbital CDI.

Are There Significant Benefits of Minimally Invasive Endoscopic Thyroidectomy?

Minimally invasive surgery using endoscopic vision is widely employed for the treatment of thyroid diseases. We have performed endoscopic thyroidectomy by the axillary approach (axillary approach) and video-assisted thyroidectomy via a 3 cm cervical incision (video-assisted approach). In this study, we evaluated the efficacy of these two procedures. Each procedure was performed in 20 consecutive consenting patients. The degree of invasiveness after surgery was compared using postoperative results. The amount of pain and satisfaction with surgery was evaluated by grade (1-5) using a patient questionnaire. All thyroidectomies were completed successfully. No recurrent laryngeal nerve palsies occurred. Operating time for the video-assisted approach was significantly shorter than that for the axillary approach (p < 0.01). The amount of pain for the axillary approach on 1, 3, and 5 days after operation, respectively, was graded 3.2+/-0.7, 2.1+/-0.6, and 1.6+/-0.7 compared to 2.7+/-1.1, 1.7+/-0.7, and 1.1+/-0.2 for the video-assisted approach. The postoperative course was significantly less painful in patients undergoing the video-assisted approach on postoperative days 3 and 5 (p < 0.01). The degrees of satisfaction for the axillary approach and the video-assisted procedure were 1.2+/-0.4 and 2.4+/-1.0, respectively (p < 0.01). The video-assisted approach is less "invasive" than the axillary approach, but the axillary approach may be indicated for patients who are anxious about the visible cosmetic results.

Medullary thyroid carcinoma: nationwide Japanese survey of 634 cases in 1996 and 271 cases in 2002

Medullary thyroid carcinoma (MTC) occurs sporadically or as an inherited disease, with the latter occurring in the form of multiple endocrine neoplasia (MEN) type 2A, MEN type 2B, or familial non-MEN medullary carcinoma (FMTC). MTC is inherited as an autosomal dominant trait and is associated with germline mutations of the RET proto-oncogene. Genetic testing identifies carriers of the mutant gene and enables preventive thyroidectomy. A nationwide questionnaire-based survey was conducted in 1996 and again in 2002, and we report here the results of the two surveys that characterize the clinical course of the inherited form of MTC. The data show a higher rate of inherited MTC than previously described, although MEN2A was found to be the most common inherited form of MTC, the same as in earlier studies. The most important finding was the difference in method of detection of MTC between the two surveys. Since the discovery of the genetic association with the disease, genetic testing has become the diagnostic method of choice, replacing indicators such as neck mass and elevated non-stimulated serum calcitonin level. Genetic testing enables early detection of the disease, which provides patients with the possibility of better outcome.

Role of Arginine Residues on the S4 Segment of the Bacillus halodurans Na+ Channel in Voltage-sensing

The one-domain voltage-gated sodium channel of Bacillus halodurans (NaChBac) is composed of six transmembrane segments (S1-S6) comprising a pore-forming region flanked by segments S5 and S6 and a voltage-sensing element composed of segment S4. To investigate the role of the S4 segment in NaChBac channel activation, we used the cysteine mutagenesis approach where the positive charges of single and multiple arginine (R) residues of the S4 segment were replaced by the neutrally charged amino acid cysteine (C). To determine whether it was the arginine residue itself or its positive charge that was involved in channel activation, arginine to lysine (R to K) mutations were constructed. Wild-type (WT) and mutant NaChBac channels were expressed in tsA201 cells and Na+ currents were recorded using the whole-cell configuration of the patch-clamp technique. The current/voltage (I-V) and conductance/voltage (G-V) relationships steady-state inactivation (h(infinity)) and recovery from inactivation were evaluated to determine the effects of the S4 mutations on the biophysical properties of the NaChBac channel. R to C on the S4 segment resulted in a slowing of both activation and inactivation kinetics. Charge neutralization of arginine residues mostly resulted in a shift toward more positive potentials of G-V and h(infinity) curves. The G-V curve shifts were associated with a decrease in slope, which may reflect a decrease in the gating charge involved in channel activation. Single neutralization of R114, R117, or R120 by C resulted in a very slow recovery from inactivation. Double neutralization of R111 and R129 confirmed the role of R111 in activation and suggested that R129 is most probably not part of the voltage sensor. Most of the R to K mutants retained WT-like current kinetics but exhibited an intermediate G-V curve, a steady-state inactivation shifted to more hyperpolarized potentials, and intermediate time constants of recovery from inactivation. This indicates that R, at several positions, plays an important role in channel activation. The data are consistent with the notion that the S4 is most probably the voltage sensor of the NaChBac channel and that both positive charges and the nature of the arginine residues are essential for channel activation.

Surgery for hepatocellular carcinoma with tumor thrombus extending into the right atrium: report of a successful resection without the use of cardiopulmonary bypass

Hepatocellular carcinomas, of which the tumor thrombus extends into the right atrium via the inferior vena cava, may soon cause fatal complications. Only surgery can be an effective treatment. This procedure usually needs the aid of cardiopulmonary bypass. We recently experienced a successful surgery to remove thrombus combined with hepatectomy. Reporting the detailed technique, both associated diagnosis and intraoperative management are discussed herein. We were able to perform hepatectomy of tumor thrombus in the right atrium without the use of cardiopulmonary bypass or veno-venous bypass. The tumor thrombus was removed from the right atrium into the suprahepatic inferior vena cava by reducing the liver on the tail side. And after total hepatic vascular exclusion was achieved, the intracaval tumor thrombus and the right lobe of the liver were removed en bloc. The operation took 545 minutes and the total hepatic vascular exclusion period was 32 minutes. The postoperative course was uneventful. There are some key points for this procedure. Preoperative or intraoperative US is essential in judging whether tumor thrombus can be removed from the right atrium into the inferior vena cava by reducing the liver or not. Test clamping of the inferior vena cava prior to total hepatic vascular exclusion will enable us to judge whether veno-venous bypass during total hepatic vascular exclusion is needed or not. Surgery without the use of cardiopulmonary bypass is safe and can be minimally invasive when it is performed with a reliable diagnosis and technique.

Effective treatment with chemotherapy and surgery for advanced small cell carcinoma of the esophagus

A 78-year-old man reported a persistent midthoracic pain, mild dysphagia, and an abdominal distention. An abdominal computed tomography scan showed massive ascites, extensive paracardial mass, a large mass which invaded the pancreas, and a mass of multiple para-aortic lymphadenopathies which involved the superior mesenteric artery. An upper gastrointestinal endoscopic study revealed an infiltrative, ulcerating tumor of the lower esophagus. Histological study of the biopsy specimens from esophageal tumor showed small cell carcinoma. After combination chemotherapy, an abdominal computed tomography scan showed a disappearance of asites, a partial response reduction of paragastric mass, peripancreatic mass and para-aortic lymphadenopathies. Histological study of the biopsy specimens from esophageal tumor showed a viable small cell carcinoma. In June 2001, the patient underwent lower esophagectomy and proximal gastrectomy combined with splenectomy and distal pancreatectomy through an abdominal approach. Histological findings of the resected specimen showed that the esophageal tumor was a small cell carcinoma which invaded into the submucosal layer, and both paracardial and peripancreatic tumors, and all lymph nodes had no cancer cells. The patient's postoperative recovery was uneventful and discharged without aggressive chemotherapy postoperatively. However, he eventually died of progression of the metastasis 21 months after first detection of the carcinoma. Patients with esophageal small cell carcinoma treated with surgery following chemotherapy and/or radiotherapy have been reported to survive longer than those treated with chemotherapy and/or radiotherapy. Therefore, surgical resection may be recommended as the second therapy that occasionally produces long-term remission and possibly long-term survival for patients with small cell carcinoma of the esophagus.

Radiological and surgical management of thyroid neoplasms

Recent advances in the radiological diagnosis in thyroid neoplasms have been achieved by high-resolution ultrasonography and color-Doppler, and the ultrasound-guided fine-needle aspiration biopsy and ultrasound-guided percutaneous ethanol injection therapy have been developed on the basis of these modalities. Ultrasonography and ultrasound-guided fine-needle aspiration biopsy have made minimally invasive thyroid surgery possible. The surgical procedures are classified into three main categories according to the approach, and each approach has its own advantages and disadvantages. Surgeons have to select the most suitable approach from one of these categories of approaches for each patient with a thyroid neoplasm.

Clinical manifestations of familial medullary thyroid carcinoma

We conducted a large-scale nation-wide questionnaire survey to ascertain the status of familial medullary thyroid carcinoma (MTC) in Japan in 2002. Out of a total of 271 MTC cases (male to female ratio 1:1.4), multiple endocrine neoplasia (MEN) 2A accounted for 83 cases (30.6%), familial MTC (FMTC) for 14 cases (5.1%), MEN for 11 cases (4.1%), and sporadic MTC for 163 cases (60.1%). Mean age at the time of diagnosis was 35.6 in MEN2A, 34.6 in FMTC, 30.5 in MEN2B, and 47.6 in sporadic MTC. Forty-five percent of MEN2A patients had pheochromocytoma and 11% of MEN2A patients had parathyroid disorders when MTC was diagnosed. Finally, the RET oncogene test yielded the largest number of initial findings that led to diagnosis of familial MTC.

[The RET gene in multiple endocrine neoplasia type 2 (MEN 2)]

Multiple endocrine neoplasia types 2A and 2B(MEN 2A and MEN 2B), and familial medullary thyroid carcinoma(FMTC) are autosomal, dominantly inherited syndromes involving endocrine tumors. MEN 2A is characterized by medullary thyroid carcinoma(MTC), pheochromocytoma(pheo), and parathyroid hyperplasia; MEN 2B is characterized by MTC, pheo, mucosal ganglioneuroma, and marfanoid habitus. Affected individuals in FMTC families develop MTC without any other abnormalities. MEN 2A and MEN 2B and FMTC are caused by germline mutations in the RET proto-oncogene. To investigate the spectrum of RET mutations among Japanese patients, we analyzed the RET gene 118 patients with MEN 2 or FMTC.

Aortic valve replacement for a patient with porcelain aorta and retrosternal gastric tube reconstruction after esophageal resection

A 67-year-old woman with congestive heart failure due to aortic stenosis and regurgitation needed aortic valve replacement. She had undergone right radical mastectomy 23 years before, and total thoracic esophagectomy with retrosternal gastric tube reconstruction 11 years before. Plain computed tomography showed coincident porcelain aorta. Aortic valve replacement was performed through a median sternotomy approach. Blunt dissection on anterior and right side of the gastric tube could be done with minimal injury, and the heart was exposed as in usual cardiac surgery. Preoperative multi-detector computed tomography revealed inhomogeneous and patchy distribution of calcification in the ascending aorta, and was helpful to decide aortotomy site. Aortic valve replacement was done and aortotomy was closed with felt strip buttressed running suture. Postoperative course was uneventful.

Composite metastatic carcinoma in lymph nodes of patients with concurrent medullary and papillary thyroid carcinoma: a report of two cases

Synchronous occurrence of medullary and papillary carcinoma of the thyroid gland is very rare. We describe two cases of synchronous medullary and papillary carcinoma of the thyroid. In both cases, medullary carcinoma and papillary carcinoma were separate in the thyroid but mixed in some of the lymph node metastases. A review of the literature and our own cases revealed that composite medullary and papillary carcinoma metastases in the lymph nodes is a common feature of patients with synchronous medullary and papillary carcinoma of the thyroid gland.

FAP associated thyroid carcinoma in mother and her daughter

A 21 year-old Japanese female was referred to the hospital for evaluation of a mass in her neck. Cytologic samples obtained through fine needle aspiration (FNA) material from the mass showed pseudopapillary or sheet-like clusters. The cells had oval nuclei and columnar cytoplasms. Nuclear groove and intranuclear inclusions were scarcely seen. The cells had a cribriform or solid pattern, unlike cells in papillary thyroid carcinoma. This distinct cytological appearance is thought to belong to FAP (familial adenomatous polyposis)-associated thyroid cancer. The patient was diagnosed with FAP associated papillary thyroid carcinoma. FAP was confirmed by colonoscopy. Her mother, 48 years old, also detected an anterior neck swelling at the time of her daughter's admission. At the age of ten, the mother had undergone total colectomy because of FAP. FNA of the mass demonstrated the same cytological appearance as from her daughter's tumor. Total thyroidectomy was performed. Gross and microscopic appearances of the tumor was similar in mother and daughter. We believe it is possible to detect FAP through FNA cytology of thyroid tumors if pathologists are aware of the unique cytohistological features of thyroid tumor cells in FAP.

[Sentinel node navigation surgery in patients with thyroid carcinoma]

Performing prophylactic or elective modified dissections of the neck in patients with clinically occult lymph nodal metastases from thyroid cancers is controversial since metastases to the lymph nodes are associated with high rates of recurrence. Biopsies of sentinel lymph nodes can be performed successfully in patients with thyroid cancers since they can be identified with dyes or 99mTc. Our preliminary findings indicate that biopsies of sentinel lymph nodes can be useful in the treatment of thyroid cancers, although, the clinical significance of identifying metastases in regional lymph nodes using this technique remains to be determined.

Double parathyroid carcinoma

The incidence of parathyroid carcinoma is rare. We recently encountered a case of double carcinoma, located in the right and left upper parathyroid glands. A 67-year old man came to the Teikyo University Hospital because of his bilateral parathyroid masses with hypercalcemia and high parathyroid hormone (PTH). Preoperative diagnoses were parathyroid adenoma in the left lobe and papillary thyroid carcinoma or parathyroid carcinoma in the right lobe. First, the left tumor was removed; however, iPTH was still high. The right mass was then resected and iPTH fell to normal range. Histological examination revealed both tumors were parathyroid carcinoma. To the best of our knowledge, this is the first report of double parathyroid carcinoma confirmed histologically.

Detection of sentinel lymph nodes in patients with papillary thyroid cancer

OBJECTIVES

To determine the feasibility of sentinel lymph node biopsy as a means of evaluating the cervical lymph nodes of patients with papillary thyroid cancer.

METHODS

Isosulfan blue dye was injected around the tumour of 68 patients with papillary thyroid cancer; sentinel lymph node biopsy was performed in addition to subtotal thyroidectomy and central and modified lateral neck lymph node dissections. Surgical specimens were examined by routine processing to determine whether metastasis was present.

RESULTS

Sentinel lymph nodes were identified in 63 (92.6%) of the 68 patients. There was concordance between the sentinel lymph node status and the final regional lymph node status in 58 (92.1%) of the 63 patients. There were five false-negative cases. Sentinel lymph node biopsy had a sensitivity of 87.5% (35/40), specificity of 100% (23/23), positive predictive value of 100% (35/35), negative predictive value of 82.1% (23/28), and accuracy of 92.1% (58/63).

CONCLUSIONS

Sentinel lymph node biopsy may allow discrimination between patients with true lymph-node-negative papillary thyroid carcinoma and those with non-palpable metastatic lymph nodes. It may also be helpful in diagnosing metastases and avoiding unnecessary lymph node dissection in thyroid cancer.

Reliable cervical anastomosis through the retrosternal route with stepwise gastric tube

OBJECTIVES

An extra-anatomic reconstruction would be beneficial in preventing recurrent malignant dysphagia. A long gastric tube that allowed a sufficient blood flow was necessary to perform the successful cervical anastomosis through the retrosternal route.

METHODS

The gastric tube was created by means of separate division and closure of the seromuscular and submucosal-mucosal layers (stepwise group) in 15 consecutive patients and by means of full-thickness cutting of the stomach and closure of the seromuscular layer (standard group) in 22 patients. We compared these 2 types of gastroplasties in terms of total length of the tube, blood flow, and the incidence of anastomotic leakage. Blood flow was measured with a laser Doppler flowmeter during surgical intervention.

RESULTS

The gastric tube in the stepwise group was significantly longer than that in the standard group (P <.01, unpaired t test). Tissue blood flow at the site of anastomosis in the stepwise group was significantly greater than that in the standard group (P <.01, unpaired t test), and the rate of anastomotic leakage in the stepwise group was significantly lower than that in the standard group (P <.05, chi(2) test).

CONCLUSION

We consider this technique to be a useful procedure for retrosternal reconstruction after subtotal esophagectomy.

Minimally invasive surgery for gastric carcinoid tumor

Minimally invasive laparoscopic wedge resection for gastric mucosal carcinoma and submucosal tumor was first performed in Keio University hospital in 1992. Since then, 172 gastric tumor patients, including four cases of carcinoid tumor, have been successfully treated at the Keio University hospital using this procedure. No local disease recurrence or distant metastases have been observed in follow-ups over as long as 10 years. Chronic atrophic gastritis patients with carcinoid tumors occurring secondary to hypergastrinemia are candidates for the minimally invasive surgery. With careful patient selection according to tumor size, depth of invasion, and histopathological findings of malignancy grade, endoscopic and laparoscopic therapy for these patients can be a safe, curative, and minimally invasive procedure.