Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0007097 (carcinoma)
 152,788 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To determine whether (18)fluorodeoxyglucose-positron emission tomography (FDG-PET) for the detection of recurrences or metastases of differentiated thyroid carcinoma should be performed during thyrotropin (TSH) suppression or TSH stimulation, eight patients were studied sequentially. After the second FDG-PET scan, a therapeutic (131)I dose was administered with posttherapy scans obtained 10 days later. Both FDG-PET scans were compared with each other and with the (131)I posttherapy whole body scans by two independent observers. Findings were verified using other imaging modalities or biopsies. Median TSH was 0.04 mU/L during TSH suppression and 64 mU/L during TSH stimulation. The FDG-PET scans during TSH suppression showed abnormalities in four patients and the FDG-PET scan during TSH stimulation in five patients. One patient was only positive during TSH stimulation. In two other patients the FDG-PET scan during TSH stimulation clearly identified more lesions, and in all positive patients lesion contrast was better during TSH stimulation. In two patients FDG-PET findings during TSH stimulation led to a change in clinical management. Thus, the performance of FDG-PET during TSH stimulation was either superior or equal to FDG-PET during TSH suppression, but never inferior. To detect metastatic or recurrent differentiated thyroid carcinoma FDG-PET should be performed during hypothyroidism, leading to TSH stimulation.
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PMID:Better yield of (18)fluorodeoxyglucose-positron emission tomography in patients with metastatic differentiated thyroid carcinoma during thyrotropin stimulation. 1209 98

In patients with cervical cancer of an unknown primary (CUP), no established concept exists for the necessary diagnostic procedures. In order to find the primary tumor, extensive diagnostic steps are generally recommended; however, they are often not performed consistently. In the current study, we consistently used a diagnostic algorithm and analyzed its consequences on patients' prognoses. We retrospectively studied 57 patients who were found to have a cervical metastasis of the upper- or midneck and an unknown primary tumor after routine examination of the head and neck region. Patients were analyzed for the value of applied diagnostic measures, tumor classification, survival rates and frequencies of subsequent lymph node or distant metastases after the initial treatment. Our results showed that a diagnostic algorithm (lymph node biopsy, rigid panendoscopy with systematic biopsies of suspect regions as well as blind biopsies of endoscopically inconspicuous regions, including the tongue base and nasopharynx and bilateral tonsillectomy) led to the detection of 14 occult oropharyngeal and 5 nasopharyngeal primary tumors in the patients. These tumors were primarily diagnosed as CUP. Oropharyngeal tumors either grew submucosally or were so small that only microscopic evaluation of the entire tonsil uncovered the tumor. Imaging procedures (X-ray, ultrasound, CT, MRT and FDG-PET) as well as gynecological, urological and gastroenterological consultations did not reveal the primary tumors in any of the cases. The 3-year survival rate for the patients with occult oropharyngeal primary tumors was 100% after treatment, while the patients in which our diagnostic schedule did not reveal a primary tumor showed a survival rate of 58%. The prognosis of all of the patients with cervical carcinoma metastasis was dependent on the initial nodal stage. Metachronous metastasis after completion of the initial treatment was prognostically infaust, while secondary detection of the primary tumor was worthwhile during follow-up as long as further treatment options were offered. The prognosis of patients with cervical carcinoma metastases of the upper- and midneck is much more favorable than that of patients with a CUP syndrome of other localizations. Identification of an occult pharyngeal tumor is prognostically relevant, since it opens up the possibility of specific locoregional treatment. In patients with cervical CUP, blind but systematic pharyngeal biopsies, including bilateral tonsillectomy, should be performed.
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PMID:Diagnostic strategies in cervical carcinoma of an unknown primary (CUP). 1211 82

Evaluation of patients with known or suspected recurrent colorectal carcinoma is now an accepted indication for FDG PET imaging. FDG PET does not replace imaging modalities such as CT for preoperative anatomic evaluation but is indicated as the initial test for diagnosis and staging of recurrence and for preoperative staging (N and M) of known recurrence that is considered to be resectable. FDG PET imaging is valuable for differentiation of posttreatment changes from recurrent tumor, differentiation of benign from malignant lesions (indeterminate lymph nodes, hepatic and pulmonary lesions), and evaluation of patients with rising tumor markers in the absence of a known source. Addition of FDG PET to the evaluation of these patients reduces overall treatment costs by accurately identifying patients who will and will not benefit from surgical procedures. Although initial staging at the time of diagnosis is often performed during colectomy, FDG PET imaging is recommended for a subgroup of patients at high risk (with elevated CEA levels) and normal CT and for whom surgery can be avoided if FDG PET shows metastases. Screening for recurrence in patients at high risk has also been advocated. FDG PET imaging seems promising for monitoring therapy, but larger studies are necessary.
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PMID:Positron emission tomography for evaluation of colorectal carcinoma. 1213 65

This prospective study was performed to evaluate the ability of a dual-head gamma camera with fluorine-18 fluorodeoxyglucose coincidence detection emission tomography (FDG-CDET) to detect primary tumor and cervical lymph nodes in head and neck squamous cell carcinoma (HNSCC), and to show the response of the carcinoma to chemotherapy. The findings were compared with those of physical examination, computed tomography (CT), and histopathology, before treatment in 61 patients, and after induction chemotherapy in 34 of them. Before treatment, the primary was detected in 93%, 79%, and 95% of cases on panendoscopy, CT, and FDG-CDET, respectively. After chemotherapy, 34 patients were evaluable for response of the primary tumor. Surgical resection was performed in 23 of them: agreement with histopathologic results for response to treatment was 74%, 69%, and 78% for panendoscopy, CT, and FDG-CDET, respectively. No surgical resection was performed in 11 of the 34 patients, but biopsies were performed before radiotherapy, and their rates of agreement with histopathologic results for response to treatment were 75%, 75%, and 67% on panendoscopy, CT, and FDG-CDET, respectively. For cervical lymph nodes, 245 sites were resected in 41 patients, and FDG-CDET appeared competitive with CT in detecting metastatic neck disease, especially after neoadjuvant chemotherapy; the accuracy was 93%. These results demonstrated the ability of FDG-CDET to detect primary tumors and cervical lymph nodes in HNSCC and to show its response to chemotherapy, as compared to the ability of CT and panendoscopy. It may be a complementary tool to evaluate residual disease after induction chemotherapy, although higher sensitivity would be required for FDG-CDET to be considered as a staging modality.
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PMID:Fluorodeoxyglucose imaging using a coincidence gamma camera to detect head and neck squamous cell carcinoma and response to chemotherapy. 1229 28

The patient's prognosis is significantly related to para-aortic lymph node metastasis in advanced cervical cancer. Magnetic resonance imaging (MRI) has been widely performed to detect lymph node metastasis with a variable sensitivity. Therefore, in this prospective study, we evaluated FDG-PET to detec para-aortic lymph nodal metastasis in locally advanced cervical carcinoma with negative MRI findings. Forty-two women with advanced cervical cancer and negative abdominal MRI findings were included in this study. Para-aortic lymph node metastases were confirmed according to para-aortic lymph-adenectomy findings. Para-aortic lymphadenectomy findings showed 12 patients with para-aortic lymph nodal metastasis. Two patients had false-negative and 1 patient had false-positive FDG-PET findings. The FDG-PET showed sensitivity of 83.3%, specificity of 96.7%, and accuracy of 92.9%. As assessment of para-aortic lymph node metastases may be essential for therapy planning, FDG-PET is an alternative tool to detect para-aortic lymph node metastases in advanced cervical cancer with negative MRI findings.
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PMID:Detecting para-aortic lymph nodal metastasis by positron emission tomography of 18F-fluorodeoxyglucose in advanced cervical cancer with negative magnetic resonance imaging findings. 1237 36

Colorectal carcinoma poses a serious public health threat. Detection in its early stages in the best predictor for long-term survival, which is the impetus for population-based screening programs. We believe that full-colon imaging by either DCBE or colonoscopy is necessary for colon cancer screening because flexible sigmoidoscopy, even if perfect, only detects 50% to 60% of colon cancers, a rate far worse than even the worst rate reported for single-contrast barium enema. Screening for colon cancer with flexible sigmoidoscopy is equivalent to performing a "left" mammogram for the detection of breast cancer. The role of CT colonography is still to be determined. When confronted with a symptomatic patient, barium enema is applied in conjunction with CT to detect primary colorectal carcinoma, to differentiate it from other benign and malignant processes involving the colon, and to assess for disease extent before surgery in selected high-risk patient populations. Pelvic MRI may be useful in the preoperative assessment of patients with rectal carcinoma as a means for assisting surgical planning. CT, MRI, and barium enema are used in postoperative follow-up for detecting local recurrence and distant spread. In response to known difficulty in discriminating between normal postoperative changes and tumor recurrence and in determining the nature of certain liver lesions, FDG-PET has been approved for the detection and localization of recurrent colorectal cancer in patients with rising CEA levels and indeterminate findings on standard imaging studies. Given its current promise of offering high sensitivity, specificity, and accuracy, the indications for PET may well expand in the future, but its final role in still to be determined.
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PMID:Radiologic imaging modalities in the diagnosis and management of colorectal cancer. 1241 53

The fact that fluorine-18 fluorodeoxyglucose ([(18)F]FDG) accumulates in inflammatory lesions as well as in tumours reduces the diagnostic specificity of positron emission tomography (PET) in oncology. The aim of this study was to characterise the uptake of [(18)F]FDG in isolated human monocyte-macrophages (HMMs) in vitro in comparison with that in human glioblastoma (GLI) and pancreatic carcinoma cells (PAN). The purity of HMM preparations was determined by immunohistochemical staining and their functional integrity was assessed by long-term incubation with iodine-131 acetylated bovine serum albumin. [(18)F]FDG uptake in HMMs was quantified as percent of whole [(18)F]FDG activity per well (% ID) or as % ID in relation to total protein mass. [(18)F]FDG uptake in HMMs significantly increased with culture duration, yielding 7.5%+/-0.9% (% ID/100 micro g) at day 14. Stimulation by lipopolysaccharide further enhanced [(18)F]FDG uptake in HMMs by a factor of 2. [(18)F]FDG uptake significantly decreased with increasing glucose concentration in the medium. Radio-thin layer chromatography of intracellular metabolites revealed that [(18)F]FDG was trapped by HMMs mainly as [(18)F]FDG-6-phosphate and [(18)F]FDG-1,6-diphosphate. [(18)F]FDG uptake was in the range of uptake values measured in GLI and PAN. By accumulating [(18)F]FDG in a manner analogous to uptake by tumour cells, activated HMMs may contribute to the [(18)F]FDG uptake values measured by PET in neoplasms.
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PMID:Uptake of [18F]fluorodeoxyglucose in human monocyte-macrophages in vitro. 1255 45

High-risk differentiated thyroid carcinoma is the most frequent thyroid tumor of "poor prognosis": this mainly includes patients with extra-thyroidal invasion, or distant metastases, younger patients (<16 years old), and older patients (>45 years old). Among them, metastatic patients with multiple organ involvement at the time of initial diagnosis have the higher risk of cancer death. Additionally, certain histological subtypes are classically more aggressive, and bilateral cervical lymph-nodes metastases or mediastinal involvement may also impart a poorer overall prognosis. More aggressive therapy to produce undetectable thyrotropin levels is usually recommended, although the benefit of such therapy and how long to maintain thyrotropin suppression has not been definitively established. As about two-thirds of the recurrences occur within the first decade after initial treatment, this first decade seems particularly critical, even if follow-up is necessary throughout the patient's life as recurrences may also occur over several decades. Coupled thyroglobulin (Tg) and Tg antibody (TgAb) assay is the first-line tool in their follow-up. Tg measurement obtained either after LThyroxine withdrawal or rhTSH stimulation may permit the selection of patients for scanning with a high dose of 131-I. When either basal Tg level is high or TgAb increases, it appears preferable to schedule patients directly for 131-I therapy followed by a post-therapy WBS. Therefore, the discovery of foci of 131-I uptake is possible in 60 to 80% of such patients. 131-I therapy is proposed as long as metastases trap 131-I without any limit to the cumulative dose of 131-I, although the risk of leukemia rises slightly above a 500 mCi (18,500 MBq) cumulative dose. But when 131-I post therapeutic WBS is negative, any further administration of 131-I is not justified. Alternative imaging procedure is thus required to detect metastases that have lost their capacity to concentrate 131-I. Conventional imaging with ultrasonography of the neck, a CT scan or an MRI of the neck and the chest and bone imaging, and even non-conventional imaging with other isotope procedures, such as 18-FDG whole-body scanning, are nowadays indicated. The goal is to localize those metastases in order to propose the more adequate therapeutic options.
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PMID:Follow-up of thyroid cancer patients with "poor prognosis". 1270 40

The large numbers of studies on the postoperative management of differentiated thyroid carcinoma allows us to use adjuvant treatment and follow-up studies more selectively based on patient risk for recurrence and mortality. Recurrent differentiated thyroid carcinoma is more easily and more effectively treated with early diagnosis. With this in mind, patients who are at high risk for life-threatening recurrent disease should be treated aggressively and followed up expectantly. In these patients, adjuvant treatment with 131I ablation and thyroid hormone suppression is appropriate. External irradiation may be considered, especially for patients with postoperative residual disease. Close follow-up with stimulated thyroglobulin and 131I whole body scans should be performed to facilitate early detection of recurrent disease. Low-risk patients may be effectively treated with more conservative management. 131I ablation has not resulted in improved survival in these patients. Follow-up with serum thyroglobulin after initial negative 131I whole body scan may be appropriate in these patients. Management of patients at intermediate risk remains controversial. Recombinant human thyrotropin allows us to obtain stimulated serum thyroglobulin and promises the ability to perform 131I ablation and whole body scan without the need for thyroid hormone withdrawal. Functional radionuclide imaging, such as FDG PET, now allows us to localize recurrent disease in patients with elevated serum thyroglobulin but negative 131I scan.
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PMID:Postoperative management of differentiated thyroid cancer. 1280 14

Accurate preoperative staging is essential for the indication and selection of the appropriate surgical procedure in patients with esophageal cancer. The present prospective study was designed to determine if the preoperative use of (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) increases the accuracy of staging esophageal cancer compared with computed tomography (CT) and if it thereby leads to a different therapeutic approach. A total of 58 patients, 46 men and 12 women (mean age 61 years), with histologic proof of esophageal carcinoma underwent FDG-PET of the neck, chest, and abdomen, as well as CT of the chest and abdomen, to determine tumor stage. FDG-PET and CT data were compared with each other and with pathohistologic findings. Sensitivity, specificity, and overall accuracy for detecting histologically verified lymph node and distant metastases were calculated for FDG-PET and CT. FDG-PET showed a higher specificity, whereas CT had higher accuracy for detecting both abdominal (73% vs. 59%) and thoracic (73% vs. 63%) lymph node metastases. The accuracy of detecting blood-borne and lymphatic distant metastases was identical for CT and FDG-PET imaging (50%). FDG-PET had a higher specificity than CT (87% vs. 13%) but lower sensitivity (35% vs. 67%). FDG-PET did not provide new information on the indication for surgery, nor was it helpful for choosing the appropriate surgical procedure in patients with esophageal carcinoma. In view of the relatively high cost of FDG-PET examinations, the use of this modality is indicated primarily in patients with inconclusive CT findings or for scientific research projects. Higher sensitivity as a result of tumor-affinity radiopharmaceuticals and optimized apparatus resolution, in addition to the advantages offered by whole-body PET scanning, may lead to new indications for this staging procedure in the future.
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PMID:Positron emission tomography for staging esophageal cancer: does it lead to a different therapeutic approach? 1291 69


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