Biomedical subjects

Theresia Weber

Publications and source records attributed to Theresia Weber.

7 recordsLinked to original sources

PubMed2006

Localization of hyperfunctioning parathyroid glands by selective venous sampling in reoperation for primary or secondary hyperparathyroidism.

BACKGROUND: Localization of hyperfunctioning parathyroid glands in patients with previous cervical operations is not always successful with noninvasive methods such as ultrasound, sestamibi scan, or magnetic resonance imaging. The aim of our study was to evaluate the results of selective venous sampling (SVS) of intact parathyroid hormone (PTH) in patients undergoing surgery for primary (75%) or secondary (25%) hyperparathyroidism (HPT). METHODS: Between January 2000 and January 2006, SVS for PTH was performed in 51 consecutive patients with persistent or recurrent HPT or patients with previous cervical explorations. The results of SVS were compared with those of noninvasive localization studies. RESULTS: Successful surgical treatment was achieved in 47 of 51 patients (92%). SVS had a sensitivity of 83.3% for the correct localization of a parathyroid adenoma (79.5%) or hyperplastic parathyroid glands (91.6%). False-positive or indeterminate results of SVS were found in 6% and 2%, respectively, of the patients. Ultrasound detected enlarged parathyroid glands with a sensitivity of 33.3%, and sestamibi scan with a sensitivity of 57.1%. CONCLUSIONS: Compared with noninvasive localization studies, SVS for PTH yielded the best results for recurrent or persistent HPT and for patients with previous neck explorations. SVS is strongly recommended in reoperative surgery for HPT with indeterminate results of noninvasive methods.

Adult↗

PubMed2006

Thyroid carcinoma.

PURPOSE OF REVIEW: Diagnostic methods and treatment options for differentiated and medullary thyroid carcinoma are continuously influenced by new trends and techniques. Our review therefore displays the most recent clinical practices for diagnosis and operative treatment of differentiated and medullary thyroid carcinoma. RECENT FINDINGS: Among the new diagnostic methods, high-resolution ultrasonography plays an important role for both the evaluation of thyroid nodules and the detection of enlarged suspicious cervical lymph nodes. The results of ultrasound will definitely influence operative decisions. A second step to diagnose medullary thyroid carcinoma is calcitonin measurement before surgery, which is sensitive and specific enough to detect medullary thyroid carcinoma in patients with thyroid nodules. Surgical treatment for differentiated or medullary thyroid carcinoma mostly consists of total or near-total thyroidectomy. An additional central or lateral modified-radical neck dissection might help to reduce local recurrence, especially in medullary carcinoma, but still does not influence significantly the survival rates. Monitoring of the recurrent laryngeal nerve during surgery is used increasingly. According to the newest literature, however, compared with visual identification of the laryngeal nerve, it cannot be considered as superior. SUMMARY: Diagnosis and treatment of thyroid carcinoma are still subjected to changes and the different options of surgical treatment in particular will be continuously discussed in the future.

Biomarkers↗

PubMed2005

A case of methicillin-resistant Staphylococcus aureus infection following bile duct stenting.

AIM: To present a case of methicillin-resistant Staphylococcus aureus (MRSA) infection following bile duct stenting in a patient with malignant biliary obstruction. METHODS: A 78-year-old male patient was admitted to a community hospital with progredient painless jaundice lasting over two weeks, weight loss and sweating at night. Whether a stent should be implanted pre-operatively in jaundiced patients or whether these patients should directly undergo surgical resection, was discussed. RESULTS: ERC and a biopsy from the papilla of Vater revealed an adenocarcinoma. In addition, a 7-Ch plastic stent was placed into the common bile duct. Persistent abdominal pain, increasing jaundice, weakness and indigestion led to the transfer of the patient to our hospital. A pylorus-preserving pancreatoduodenectomy was performed. Intraoperatively, bile leaked out of the transected choledochus and the stent was found to be dislocated in the duodenum. A smear of the bile revealed an infection with MRSA, leading to post-operative isolation of the patient. CONCLUSION: As biliary stents can cause severe infection of the bile, the need for pre-operative placement of biliary stents should be carefully evaluated in each individual case.

Adenocarcinoma↗

PubMed2005

Impact of intraoperative parathyroid hormone levels on surgical results in patients with renal hyperparathyroidism.

The aim of our study was to evaluate the impact of intraoperative parathyroid hormone (PTH) measurement on surgical results in patients with renal hyperparathyroidism (HPT). From December 1999 to February 2004, a series of 95 consecutive patients underwent total parathyroidectomy and intraoperative PTH measurement for renal HPT. Intraoperative PTH was measured before and 15 minutes after parathyroidectomy with the Immulite DPC assay for intact PTH. The median PTH levels before surgery were 133.0 pmol/L, which declined to 5.9 pmol/L at the end of the operation. At follow-up, 91 of 95 (96%) patients presented with normal calcium levels. Persistent renal HPT was seen in three patients, and recurrent HPT was diagnosed in another. In 99% of the patients the intraoperative PTH levels declined more than 50% and in 73% the PTH decay was more than 90%. In 64% of the patients PTH levels dropped into the normal range (< 7.6 pmol/L). Altogether, 97% of the patients with an intraoperative PTH decrease of more than 90% presented with normal PTH levels postoperatively (p = 0.0237), as did all of the patients whose intraoperative PTH dropped into the normal range (p = 0.0432). Intraoperative PTH measurement with a decrease in intraoperative PTH of at least 90% is highly predictive of successful parathyroidectomy and normalization of postoperative calcium and PTH levels.

Adolescent↗

PubMed2003

Detection of hematogenic and lymphogenic tumor cell dissemination in patients with medullary thyroid carcinoma by cytokeratin 20 and preprogastrin-releasing peptide RT-PCR.

Despite an extensive surgical approach only 50% of the patients with medullary thyroid carcinoma (MTC) are biochemically cured. The failure to cure a larger number of patients is a result of the early dissemination of MTC. The present study evaluates two RT-PCR based assays for the detection of disseminated tumor cells in blood, bone marrow and lymph node samples of patients with MTC. Frozen tissue and blood samples of 19 patients with MTC and 61 cervical lymph nodes of these patients were obtained intraoperatively during thyroidectomy and lymphadenectomy. Preoperative bone marrow samples were obtained from 8 patients with MTC. An expression of CK20 and preproGRP was found in all MTC tissue samples. Using CK20-PCR, disseminated MTC cells were detected in 67% of the cervical lymph nodes of patients with MTC, compared to 72% involved lymph nodes, detected by preproGRP-PCR. In 16 of 61 nodes (26%) each PCR-system detected disseminated tumor cells in histologically tumor-free lymph nodes. Disseminated tumor cells were detected with CK20-PCR and preproGRP in 5 of 18 (28%) preoperative blood samples, each. The detection of a hematogenic tumor cell dissemination by preproGRP correlated significantly with the tumor stages (p = 0.019). Circulating MTC cells were found in 3 of 8 bone marrow samples with CK20-PCR, compared to 1 of 8 samples with preproGRP-PCR. Both PCR assays are highly sensitive to detect disseminated MTC cells in blood, bone marrow and lymph node samples. Our results of disseminated MTC cells in 26% of histologically tumor-free cervical lymph nodes and in 28% of the blood samples of patients with MTC might therefore explain the low biochemical cure rates.

Adult↗

PubMed2003

Detection and prognostic relevance of cytokeratin 20 in differentiated and anaplastic thyroid carcinomas by RT-PCR.

BACKGROUND: Metastatic disease in epithelial cancer results from tumor cell dissemination. We investigated an expression of cytokeratin 20 (CK20) by reverse transcriptase-polymerase chain reaction (RT-PCR) in differentiated (DTC) and anaplastic thyroid carcinomas (ATC) and correlated the results with TNM categories and the clinical follow-up. METHODS: Tissue and blood samples of 32 patients with papillary (PTC), 17 patients with follicular (FTC), and 7 patients with ATC were obtained during operation and subjected to CK20 RT-PCR. RESULTS: An expression of CK20 transcripts was detected in 47% of the tissue samples of PTC, 71% of the FTC, and 14% of the ATC. Patients with CK20-positive FTC had a significantly better outcome than patients with CK20-negative FTCs (P=.0016). Disseminated tumor cells were found in 9 of 22 (41%) blood samples of patients with CK20-positive carcinomas. The detection of CK20 transcripts in peripheral blood correlated with tumor categories. Four of 8 (50%) patients with DTC and circulating tumor cells developed local or distant recurrence compared with 3 of 13 (23%) patients with CK20-positive carcinomas and CK20-negative blood samples. CONCLUSION: Our results suggest that CK20 might be a suitable differentiation marker in thyroid carcinomas. In patients with CK20-positive tumors, those with CK20-positive blood samples had a poorer prognosis. We suggest that patients with thyroid cancer with positive CK20 blood samples should be evaluated for further adjuvant therapies after surgery.

Adenocarcinoma, Follicular↗

PubMed2001

Detection of disseminated medullary thyroid carcinoma cells in cervical lymph nodes by cytokeratin 20 reverse transcription-polymerase chain reaction.

Local recurrence in differentiated and medullary thyroid carcinoma develops frequently from metastatic infiltration of cervical lymph nodes. Despite an aggressive surgical approach, postoperative calcitonin levels as biochemical evidence for residual cancer cells remain often elevated in patients with medullary thyroid carcinoma. In the present study, we compared the detection rates of disseminated medullary thyroid carcinoma cells in cervical lymph nodes by histopathology with reverse transcription-polymerase chain reaction (RT-PCR) amplification of cytokeratin 20 (CK20) transcripts as a more sensitive but still specific molecular parameter for residual thyroid cancer cells. Forty-two cervical lymph nodes obtained from 7 patients with CK20positive medullary thyroid carcinomas were cut into two halves, one used for conventional histology, the other subjected to RNA extraction and subsequent amplification of cytokeratin 20 transcripts. Matching results for CK20 RT-PCR and histopathology were found in 74% (31/42)of the examined lymph nodes (52% positive results, 48% negative results). Positive CK20 RT-PCR pointed to residual thyroid carcinoma cells in another 19% (8/42), in which no thyroid carcinoma cells were identified by histopathology. Histology and immunohistochemistry,however, identified tumor cells in 7% (3/42) of the analyzed lymph nodes, from which no CK20 transcript could be amplified (false-negative results). These data suggest that CK20 RT-PCR might be more sensitive to detect nodal involvement of CK20 positive medullary thyroid carcinomas than conventional histopathology. In combination with histology, it might help to identify patients with residual disease after surgery.

Adenocarcinoma, Follicular↗