Contemporary imaging for colorectal cancer

With improvements in therapy for colorectal cancer, accurate imaging has taken on an increased significance. Preoperative diagnosis of metastatic disease helps identify patients who could undergo combined resection or might benefit from systemic therapy before surgery. Accurate imaging of rectal cancer is critical in evaluating locally advanced disease treatable by combined modality therapy, including chemoradiation and surgery. Postoperative imaging enhances identification of recurrent disease that might be amenable to salvage surgery.     

FDG PET imaging in hereditary thyroid cancer

AIM: To report the role of different imaging methods in staging individuals with multiple endocrine neoplasia 2A (MEN2A) or familial medullary thyroid carcinoma (FMTC). MATERIAL AND METHODS: Fourteen newly diagnosed gene carriers underwent cervical ultrasound scanning (US), cervical and mediastinal CT, MRI and whole-body meta-[131I]iodobenzylguanidine (MIBG) scintigraphy and [18F]fluorodeoxyglucose (FDG) PET scanning. RESULTS: US identified seven true primary cancer. CT and MRI located only tumors > or =5 mm in diameter. MIBG scintigraphy and FDG PET could not identify MTC foci within the thyroid. Whole-body FDG PET identified two true-positive and one false-positive lymph node metastases. MIBG scintigraphy did not identify lymph node metastases. Total thyroidectomy was performed in 12 cases, and subtotal thyroidectomy in two subjects. CONCLUSIONS: Whole-body FDG PET and cervical US help stage individuals carrying mutant genes verifying MEN2A or FMTC.     

TI-RADS评分在甲状腺癌诊断中的应用分析

  目的  观察甲状腺癌患者超声影像特征, 通过甲状腺影像学报告及数据系统(Thyroid imaging reporting and data sys- tem, TI-RADS)对甲状腺癌性结节进行分级, 期望对甲状腺癌术前定性做出更好预测。  方法  将2008年9月至2011年8月天津医科大学总医院收治并经病例证实的甲状腺癌患者160例共235枚病灶纳入研究。对所有患者行常规彩色多普勒超声检查观察病灶的大小、数量、外部形态、边界清晰程度及病变肿块、周围血流分布特征, 235个病灶按TI-RADS分级进行评分, 评价TI-RADS评分在甲状腺恶性结节的诊断价值。  结果  本组病例所示恶性结节176枚, 其中形态欠规则, 边界不清楚144枚(81.8%), 内部不均匀低回声或稍低回声152枚(86.4%), 内部探及沙砾样钙化灶144枚病灶(81.8%)。TI-RADS分级评分4、5级160枚(90.91%), TI-RADS分级评分2、3级16枚(9.09%)。  结论  甲状腺彩超声像图中出现边界不清, 形态不规则, 低回声或稍低回声肿块, 肿块内探及沙砾样钙化灶, 肿块内部丰富血流信号是诊断甲状腺癌的重要指标, 甲状腺癌病灶结节中TI-RADS分级评分为4、5级者有较高阳性率, 对甲状腺癌术前定性预测有一定意义。      

Contemporary considerations in adjuvant radioiodine treatment of adults with differentiated thyroid cancer

Differentiated thyroid cancer (DTC) is the most common endocrine malignancy with a growing incidence worldwide. The initial conventional management is surgery, followed by consideration of ¹³¹I treatment that includes three options. These are termed remnant ablation (targeting benign thyroid remnant), adjuvant (targeting presumed microscopic DTC) and known disease (targeting macroscopic DTC) treatments. Some experts mostly rely on clinicopathologic assessment for recurrence risk to select patients for the ¹³¹I treatment. Others, in addition, apply radioiodine imaging to guide their treatment planning, termed theranostics (aka theragnostics or radiotheragnostics). In patients with low-risk DTC, remnant ablation rather than adjuvant treatment is generally recommended and, in this setting, the ATA recommends a low ¹³¹I activity. ¹³¹I adjuvant treatment is universally recommended in patients with high-risk DTC (a primary tumor of any size with gross extrathyroidal extension) and is generally recommended in intermediate-risk DTC (primary tumor >4 cm in diameter, locoregional metastases, microscopic extrathyroidal extension, aggressive histology or vascular invasion). The optimal amount of ¹³¹I activity for adjuvant treatment is controversial, but experts reached a consensus that the ¹³¹I activity should be greater than that for remnant ablation. The main obstacles to establishing timely evidence through randomized clinical trials for ¹³¹I therapy include years-to-decades delay in recurrence and low disease-specific mortality. This mini-review is intended to update oncologists on the most recent clinical, pathologic, laboratory and imaging variables, as well as on the current ¹³¹I therapy-related definitions and management paradigms, which should optimally equip them for individualized patient guidance and treatment.     

Surgery for thyroid cancer

A technique of thyroidectomy that facilitates resection of the thyroid, preserves the parathyroid glands with their blood supply, and preserves the recurrent and the superior laryngeal nerves is described. This technique provides a simple and versatile means of complete extracapsular thyroidectomy for lesions of the thyroid gland and minimizes postoperative complications.     

Chemotherapy for thyroid cancer

Twenty-nine patients with advanced thyroid cancer have been treated with sequential chemotherapy regimes using the single agents etoposide, carboplatin, cis-platinum or methotrexate, and the combination of adriamycin, bleomycin and vincristine (ABC). Indications for chemotherapy were progressive, symptomatic recurrent or metastatic disease unresponsive to conventional treatment, or advanced anaplastic carcinomas. In these 29 patients there were a total of 60 evaluable drug exposures: 4 out of 22 responded to etoposide, 2 out of 9 responded to carboplatin, 5 out of 13 responded to cis-platinum, 1 out of 3 responded to methotrexate and 5 out of 13 responded to ABC. There was only one complete response in this series, seen with etoposide. Patients under 65 years and those with medullary carcinoma had the highest response rates. Mean survival in these 29 patients was 11.9 months. Mean survival in responders was 19 months compared to 5.4 months in non-responders. Etoposide, carboplatin and cis-platinum used as single agents are active in thyroid carcinoma and useful symptom control and improved survival may be achieved in those patients responding to sequential exposure to these agents.     

Molecular imaging of advanced thyroid cancer: iodinated radiotracers and beyond

An important aspect of differentiated thyroid cancer (DTC) management is disease localization by imaging. Functional imaging of thyroid cancer with iodinated radiotracers has been employed for metastatic disease detection for long. More recently, 2-deoxy-2-[18F] fluoro-d-glucose (18F-FDG) positron emission tomography/computed tomography (PET/CT), a non-iodinated ubiquitous PET tracer, has been used to detect non-radioiodine (RAI) avid disease. Advances in molecular imaging have led to the development of newer tracers like 18F-TFB (18F-tetrafluoroborate) that are transported through the sodium–iodide symporter (NIS) as well as 68 Ga-DOTATATE that image the somatostatin receptors sub-type 2 expressed in medullary thyroid cancer and some DTC. In coming years, there will be focus on newer receptor targets like prostate-specific membrane antigen expression and endoradiotherapies and theranostics.     

Neck dissection for thyroid cancer

Decisions concerning the extent of surgical treatment for thyroid cancer remain controversial. Limited surgical procedures, designed to remove only the cancer that is clinically evident, can be successful since the primary determinants in survival are age, sex, and histologic type rather than number of positive nodes or other factors. A retrospective review of 339 patients who had surgical procedures for cancer of the thyroid at MDA hospital from 1975 to mid-1989 did not show a conclusive advantage for any type of neck dissection. The operations were tailor-made to include all evident clinical cancer. Secondary procedures, such as surgery, radioactive iodine, radiation therapy were successful in treating recurrences, which occurred in all surgical groups, whether limited or radical.     

Minimally invasive surgery for thyroid diseases and thyroid cancer

This article will review the emergence of minimally invasive thyroidectomy techniques and their applications to thyroid diseases. Minimally invasive surgical techniques for head and neck surgery have recently attracted interest. Furthermore techniques are divided into the mini-incision open, video-assisted, and complete endoscopic. Factors that determine the best operative approach include tumor size, histology, the presence of enlarged lymph nodes and evidence of local-regional invasion. Indications and contraindications for minimally invasive techniques will be discussed.     

Contemporary diagnostic approach to the thyroid nodule

Thyroid nodules are common, with an estimated incidence of 5%-10% in the United States. The current gold standard for diagnosis is fine needle aspiration biopsy (FNAB). The incidence of indeterminate diagnoses varies from 10% to 25%. Surgical resection is usually indicated to exclude the diagnosis of cancer in these patients. However, only a minority (about 20%) of indeterminate thyroid nodules actually harbor a malignancy, resulting in surgery for diagnostic purposes alone in many patients. The increased detection of benign nodules and microcarcinomas reinforces the need for improved non-operative methods to differentiate benign from malignant disease and discriminate low-risk from high-risk cancers. In this article we present a current, rational diagnostic approach to the patient with a thyroid nodule, evaluate new advances including thyroid genomic and predictor models, and propose the development of prospective trials to incorporate these new additions into clinical decision making. Given how many questions still exist for patients with thyroid nodules, partnership and collaboration, or the "bench to bedside" concept should find its way into most every thyroid surgeon and endocrinologist's lexicon.     

A radiotherapy technique for thyroid cancer

A treatment technique for treating patients with cancer of the thyroid is presented. This is a modification of “the bar-arc” technique that uses a centrally blocked moving field. We have introduced wedges and partial midline block to achieve uniform dose within the treatment volume. This enables the desired dose to be delivered to the primary, the lymph nodes and the cervical soft tissues at risk, yet keeping the dose to the spinal cord to a minimum in the cervical region and to acceptable levels in the superior mediastinum.     

Total thyroidectomy for differentiated thyroid cancer

There has been a long debate about the optimal surgical management of differentiated thyroid cancer. It has focused on the extent of thyroidectomy, with recommendations ranging from thyroid lobectomy to total thyroidectomy. There is no randomized prospective trial addressing this issue; such a trial would be prohibitive, since differentiated thyroid cancer has a good prognosis and a long natural history. Instead, there is heavy reliance on retrospective analyses, as well as consensus expert opinion and experience. We review this evidence, along with recent recommendations from several professional associations. We believe that total or near-total thyroidectomy followed by (131)I ablation and thyroid hormone suppression are most appropriate for the majority of patients with differentiated thyroid cancer, as retrospective analyses have shown that they reduce the risk of cancer recurrence, address the chance of multifocal intrathyroidal cancer, and facilitate use of surveillance scans and thyroglobulin monitoring for post-operative recurrence. This recommendation comes with the caveat that total thyroidectomy must be performed safely, since there is evidence that surgeon volume is associated with patient outcomes.     

甲状腺乳头状癌与甲状腺结节钙化的关系探讨

目前恶性肿瘤的诊断方法日益丰富,临床医师在选择检查手段时也面临多种选择,而对于同一个肿瘤不同的检查方法或许会出现截然不同的结果,对此临床医师需要全面思考和判断。现介绍1例天津医科大学附属肿瘤医院多学科综合讨论病例供大家参考。本例患者主因“恶性腹水”就诊,PET-CT检查发现甲状腺、腮腺和脐部等多处病变,考虑恶性,而B超检查考虑甲状腺和腮腺病变为良性,脐部病变为转移瘤。针吸活检诊断脐部病变为转移性腺癌,但所有检查未能确诊原发病灶。最终,经过分析其影像学表现、病理特征和免疫组化指标,多学科咨询委员会认为本例患者应诊断为腹膜癌。通过本病例讨论,认为病理诊断仍是恶性肿瘤诊断的金标准,合理的免疫组化结果对于确定癌灶的来源有较大的指导意义。     

Antibody-based imaging strategies for cancer

Although mainly developed for preclinical research and therapeutic use, antibodies have high antigen specificity, which can be used as a courier to selectively deliver a diagnostic probe or therapeutic agent to cancer. It is generally accepted that the optimal antigen for imaging will depend on both the expression in the tumor relative to normal tissue and the homogeneity of expression throughout the tumor mass and between patients. For the purpose of diagnostic imaging, novel antibodies can be developed to target antigens for disease detection, or current FDA-approved antibodies can be repurposed with the covalent addition of an imaging probe. Reuse of therapeutic antibodies for diagnostic purposes reduces translational costs since the safety profile of the antibody is well defined and the agent is already available under conditions suitable for human use. In this review, we will explore a wide range of antibodies and imaging modalities that are being translated to the clinic for cancer identification and surgical treatment.