Evaluating the role of flurodeoxyglucose PET imaging in the management of patients with sarcoidosis. Inflammatory cells in the formation of tumor-related sarcoid reactions. Romer FK. These are the lymph nodes that often become swollen when you're sick with a sore throat or cold. Internal mammary nodes, paracardiac nodes, and paravertebral nodes measure only a few millimeters. Some of the causes include: 4 Acute lymphoblastic leukemia (ALL) Cancer metastasis Coccidioidomycosis Chronic obstructive pulmonary disease (COPD) Cystic fibrosis (CF) Esophageal cancer Histoplasmosis Paratracheal lymph nodes The right and left paratracheal lymph nodes (or paratracheal chains) are groups of lymph nodes located in the throat . Mohseni S, Shojaiefard A, Khorgami Z, Alinejad S, Ghorbani A, Ghafouri A. Enlarged prevascular (anterior mediastinal) lymph nodes (arrows) are seen anterior to the brachiocephalic veins and aortic branches (A), anterior to the aortic arch and superior vena cava (B), and anterior to the superior vena cava, aortic root, and main pulmonary artery (C). Data sources include IBM Watson Micromedex (updated 5 Feb 2023), Cerner Multum (updated 22 Feb 2023), ASHP (updated 12 Feb 2023 .
Adenopathy: Symptoms, Causes, Treatment and More - Healthline Mediastinum: Lymph Node Abnormalities and Masses In the United States, mediastinal lymphadenopathy is most commonly associated with lung cancer and COPD. The wide range of pathologies may involve its own or its association with any other lung pathology.
Normal mediastinal lymph node size and number: CT and anatomic - PubMed (MEE-dee-uh-STY-num) The area between the lungs. Become a Gold Supporter and see no third-party ads. The location and purpose of these important structures. Normal lymph nodes are commonly visible on CT. The main purpose of the lymphatic system is to drain lymph from organs and tissues into the bloodstream. This means they cannot be easily felt. They filter toxins and pathogens (infectious organisms).
Mediastinal lymph nodes, mediastinal lymphadenopathy causes - Health Jade Right paratracheal, prevascular, aorticopulmonary, precarinal, subcarinal, hilar, and subhilar multiple conglomerated mediastinal lymph nodes were revealed in addition to left breast mass and axillary lymph nodes. Lung nodules usually don't cause symptoms. This system produces cells in order to fight diseases and infections. Detection of subcarinal lymph node enlargement on the posteroanterior chest radiograph was assessed in 90 patients who also had computed tomography (CT). What Is Transitional Cell Carcinoma (TCC)? 2018 Mar;5(1):713. The American Thoracic Society improves global health by advancing research, patient care, and public health in pulmonary disease, critical illness, and sleep disorders. Figure 3: annotated CT with anatomy labels, Figure 4: lymphatics of the tracheobronchial tree (Gray's illustration), see full revision history and disclosures, Hilar and interlobar zone (pulmonary nodes), inferior border: strictly the IASLC defines this as the, left (1L) and right (1R) are divided by the midline of the, left (2L) and right (2R) are divided along the left lateral border of the trachea, not the midline, inferior border of 2R: at the intersection of caudal margin of the left, inferior border of 2L: superior border of the, 3A: prevascular - anterior to the great vessels (, 3P: retrotracheal - posterior to the trachea. CS Lymph Nodes: Lung. Lots of people get terrified because a websearch tells them that is a sign of Hodgkins Lymphoma.
What are symptoms of mediastinal lymphadenopathy? Hum Pathol 2005;36:546-554. Tumors of the right upper lobe typically involve paratracheal nodes. The retrospective data of this project showed that the following factors were associated with a lower risk of lymph node metastasis: upper oesophageal cancer, high degree of differentiation, squamous-cell carcinoma, shorter tumour length, superficial invasion and some other factors.
Lymph Nodes on FDG PET/CT - Radiology Key There are many causes of mediastinal lymphadenopathy, some of which involve the lung and others that affect the body as a whole. Although a short-axis measurement of greater than 1 cm is used in clinical practice to identify abnormally enlarged nodes, it is important to realize that no node diameter clearly separates benign nodes from those involved by tumor. They found that in previous studies, where only 2-4 biopsy specimens were taken, the yield of this test was only 66% in stage I disease, and 80-85% in stage II and III disease. Lymph fluid builds up in lymph nodes in an effort to trap bacteria, viruses, or other harmful pathogens . The mediastinal nodes are a group of lymph nodes located in the thoracic cavity of the body. It is useful in detecting enlarged lymph nodes and parenchymal disease that may not be seen on conventional radiography (13). The frequent conditions involve oesophageal, breast, and thyroid cancer. The enhancement is typical of unicentric or multicentric Castleman disease. 4.2 ). However, it could be a manifestation of underlying malignancy. When you visit the site, Dotdash Meredith and its partners may store or retrieve information on your browser, mostly in the form of cookies. A right paratracheal lymph node measured 1.9 cm. At the time the article was last revised Francis Deng had no recorded disclosures. pea- or bean-sized lumps under the skin tenderness or soreness when you touch them redness and warmth of the skin over the swollen nodes Other symptoms to watch for If your lymph nodes are. Eur J Int Med 2006;17:81-87. Feel hard or rubbery, or dont move when you push on them. Primary tuberculosis usually causes unilateral hilar adenopathy. This type progresses fairly rapidly without treatment. Reprinted from Rusch, V. W., Asamura, H., Watanabe, H., et al. Does anybody know what this means? 4.9 ), infections such as tuberculosis, and sometimes sarcoidosis. When the mediastinal lymph nodes are enlarged due to a malignancy, lung cancer and lymphoma are the two most likely causes. He also had a mild MI a few weeks ago and that placed 3 stents in an artery on the back side of his heart. 4.8 ). Different values for the upper limits of normal short-axis node diameter have been found for different mediastinal node groups ( Table 4.2 ). We are trying to stay positive but this one seems confusing. This information helps the doctor decide whether more treatment, like chemo, immunotherapy, targeted therapy or radiation, might be needed after surgery. Updated September 19, 2020.. American Cancer Society. Says there are no pathologically enlarged medistinal or hilar lymph nodes. Various enlarged mediastinal nodes will be pathological, but not all will be. Conversely, few mediastinal lymphadenopathies will be visible in non-enlarged nodes. Prevascular nodes lie anterior to the great vessels and superior to the top of the aortic arch. PET is often combined with CT (PET-CT) because of the poor anatomic detail provided by PET alone. Nodes in the superior mediastinum and high paratracheal space are generally smaller and measure up to 7 mm. Thoracic lymph nodesare divided into 14 stations as defined by the International Association for the Study of Lung Cancer (IASLC) 1, principally in the context of oncologic staging. Read our, An Overview of Axillary Lymphadenopathy (Swollen Lymph Nodes in the Armpit), What to Know About a Retropharyngeal (Lymph Node) Abscess, Swollen Lymph Nodes (Adenopathy) in Cancer. What does all this read more. Smoking is one of the leading causes of cancer in the neck and head, and if you both smoke and drink alcohol, this type of cancer is even more prevalent.
Questions regarding CT CHEST/ABD - 1266724 | CancerGRACE Widened mediastinum at elderly: a challenge in the emergency room (ER Which imaging test best differentiates between sarcoidosis and malignancy when evaluating lymphadenopathy? For the purpose of prognostication, the stations may be grouped into seven zones. a Mean normal node diameter plus two standard deviations. These mediastinal tumors often begin in the nerves and are typically not cancerous. no right hilar adenopathy is seen. Pretracheal nodes are typically smaller than subcarinal nodes. Am J Roentgenol 1994;162:569-574.
Reactive Lymph Node: Definition, Symptoms, Causes, and Diagnosis A lymph node is a kidney-shaped organ in the lymphatic system and functions to trap bacterial and cancer cells. The remaining 30 had enlarged precarinal nodes on CT scan, which were greater than 15 mm from the diameter point of view.
Mediastinal Lymphadenopathy and Interstitial Lung Disease in a Cancer There ispost surgical change of 1.5 laminectomy with mild increased metabolic activity within theL5-S1severely degenerated facets. The lymphatic system is comprised of lymph nodes, the spleen, the thymus and bone marrow. In some locations, nodes that contact vessels may be difficult to identify without contrast medium infusion. Positron emission tomography (PET) is more accurate than CT in the assessment of mediastinal lymph node metastases in lung cancer and has assumed a significant role in preoperative staging. Enlarged prevascular (anterior mediastinal) lymph nodes. NOW THEY SAY IT HAS. Invasions of the diaphragm, mediastinum, heart, great vessels, trachea, carina, esophagus, recurrent laryngeal nerve, or vertebral body are termed T4 , and in the absence of mediastinal lymph node metastases are classified as stage IIIA. A list of national and international resources and hotlines to help connect you to needed health and medical services. Positron emission tomography imaging in nonmalignant thoracic disorders. Therefore, it is recommended that 8-10 biospies be obtained to increase the likelihood of achieving diagnoses. (A) At the aortic arch level, enlarged pretracheal. Distant nodes are coded in the field Mets at DX.
Benign Lymph Node Disease Involving the Mediastinum Paratracheal lymph nodes run along the sides of your trachea (windpipe) in the neck. Mediastinoscopy. Upper mediastinum nodes are usually smaller than nodes nearer the carina. J Nuc Med 1994;35:1647-1649. J Fam Pract. Am J Respir Crit Care Med 1999;160:1668-1672.
International Association for the Study of Lung Cancer (IASLC) Lymph In our case, MRI would not be useful. There are many causes of mediastinal lymphadenopathy, some of which involve the lung and others that affect the body as a whole. Swollen nodes with a bacterial infection are usually over 1 inch (25 mm) across. However, a discussion of lung cancer staging in this chapter is limited to a review of lymph node metastases and mediastinal invasion. They are most commonly involved, together with the retrocrural or retroperitoneal abdominal nodes, in patients with lymphoma or metastatic carcinoma. Mediastinal lymphadenopathy: This condition involves having swollen or enlarged lymph nodes. 90% of sarcoid patients will have an increased number of lymphocytes in their bronchoalveolar lavage fluid (21), giving it a rather high sensitivity. There are hundreds of lymph nodes in clusters around the body, but under normal circumstances, they are not palpable. Rusch VW, Asamura H, Watanabe H et-al. However, it also includes some less common causes. Abdul-Hai A, Ergas D, Katz M, Malnick SDH. These lymph nodes must filter those substances that pass through the lymphatic fluid. Lymphoma is very treatable, and the outlook can vary depending on the type of lymphoma and its stage.
What is a precarinal enlarged lymph node? - JustAnswer A proposal for a new international lymph node map in the forthcoming seventh edition of the TNM classification for lung cancer.
Mediastinal Masses: Symptoms, Diagnosis & Treatments - MedStar Health What does Precarinal lymph node mean? - Studybuff J Med Imaging Radiat Oncol.
Lymphadenopathy: Differential Diagnosis and Evaluation | AAFP 3. J Nuc Med 1998;39:1160-1166. Lymph nodes are small structures located in clusters throughout the body. However, differentiation of potentially resectable stages (stage I to stage IIIa) and stages usually considered unresectable (stage IIIb to stage IV) is important ( Table 4.4 ).
Tuberculosis From Head To Toe: (CME Available in Print Version and On Sarcoidosis can also occur in the lymphatics of the bronchovascular bundle.
2011;2011:920898. doi: 10.1155/2011/920898. a potential space bounded by the ascending aorta anteriorly, the tracheal bifurcation posteriorly, the left pulmonary artery to the left, and the right pulmonary artery to the right. Lymphadenopathy (a condition that results in enlargement of the lymph nodes) Neurogenic neoplasms (abnormal growths that develop in the thoracic spine) Extramedullary hematopoiesis (an accumulation of cells typically found inside the bone marrow in the mediastinum) What to expect at your appointment How is mediastinal lymphadenopathy treated? Brincker H. Solid tumors preceding or following sarcoidosis. 2021 May 6;1-18.doi:10.1080/17476348.2021.1920404. Swollen lymph nodes are often the first detectable sign of an illness. How many solutions does Peg Solitaire have? Cohen PR, Kurzrock R. Sarcoidosis and malignancy. Didn't find the answer you were looking for? This appearance usually fits with an infection such as Mycobacterium avium complex, Mycobacterium tuberculosis, fungal, or other bacterial infection. Mediastinoscopy was performed with biopsy and pathology was reported as granulomatous lymphadenitis. Chest 2003;124:2126-2130. The lymph nodes contain lymphocytes or white blood cells. Those less common causes include amyloidosis, sarcoidosis, silicosis, and secondary calcification to the lymphomas treatment. Others have noted patients with sarcoidosis having a higher incidence of other malignancies, mostly lung and breast, although links have been reported with many others (6). Stations 10L and 10R (Hilar Lymph nodes) are nodes that are immediately adjacent to the main-stem bronchus and hilar vessels, including the proximal portions of the pulmonary veins and main pulmonary artery, with station 10R on the right and station 10L on the left. Tracheal tumors: Tumors in your windpipe, or trachea, may be benign or malignant. AMERICAN THORACIC SOCIETY 25 Broadway New York, NY 10004 United States of America Phone: +1 (212) 315-8600 Fax: +1 (212) 315-6498 Email: atsinfo@thoracic.org. Prevascular lymph node enlargement in hodgkin lymphoma. Clinical stage was T4bN0M0 (corresponding to Stage IIIC by AJCC 7th edition). Mediastinal lymphadenopathy is a sign of an underlying disease or infection. Bronchoalveolar lavage fluid is not diagnostic of sarcoidosis, but can help narrow the differential if other testing is not available. They drain the anterior chest wall, anterior diaphragm, and medial breasts. Paraesophageal nodes lie posterior to the trachea or are associated with the esophagus, or both ( Fig. By using this Site you agree to the following, By using this Site you agree to the following, The Best IOL for 2022 RXSight Light Adjusted Lens, Will refractive surgery such as LASIK keep me out of glasses all my life.
Poligrafik.sirm.org Site Below the hila, they are difficult to distinguish from paraesophageal nodes. No data exist on the relative accuracy of radiologic methods for evaluating subcarinal nodes. The precarinal lymph nodes are present within the chest cavity around the human lungs. Stage IIIA tumors are potentially resectable. There are no areas of abnormal hypermetabolic activity within the abdominal cavity. The location of precarinal lymph nodes in the body is the pericardial space. As a result, a territory exists (the precarinal space) in which the distinction between lower paratracheal lymph nodes and hilar lymph nodes is unclear. Pulmonary emPhysema is evident. Metastatic disease, such as carcinomatosis, is the most common cause of random nodules. While malignant disease usually has higher metabolic activity than benign disease, this is not the case in sarcoid, which often shows high levels of metabolic activity (17). These lymphocytes present in the lymph nodes are responsible for the bodys protection against infection and disease. Mediastinal lymphadenopathy: a practical approach. The term is usually used to refer to lymphadenopathy or swollen lymph nodes. PET/CT combined the benefits of functional assessment with PET and anatomic assessment with CT. Read More
How to code carcinomatosis in icd 10? Explained by Sharing Culture The patient denied any cough, weight loss, night sweats, fevers, or occupational or travel-related exposures. Paraesophageal lymph node enlargement in metastatic testicular carcinoma. Regarding my Previous Post aBout my husBand CT scan with IV contrast it states as follows No mass lesions seen in the neck and superior mediastinum. The precarinal lymph nodes may extend their usual size in some individuals.
What Is a Precarinal Lymph Node? - Reference.com Drugs.com provides accurate and independent information on more than 24,000 prescription drugs, over-the-counter medicines and natural products. Pretracheal or paratracheal nodes occupy the pretracheal (or anterior paratracheal) space ( Figs. They differ in size, depending on their location. Their function is to trap cancer and bacterial cells and ensure immunity in the pulmonary region. Superior Mediastinal Nodes 2-4 2R.Upper Paratracheal 2R nodes extend to the left lateral border of the trachea. The precarinal lymph nodes are present within the chest cavity around the human lungs. There was no pleural effusion or pneumothorax (Figures 1 and 2). Secondary Causes More often than not, the cause of swollen retroperitoneal lymph nodes will be secondary, meaning that they are collaterally affected by a disease or disorder affecting an organ within or near the retroperitoneum. Eggshell calcification is most often seen in patients with silicosis or coal workers pneumoconiosis, sarcoidosis, and tuberculosis. American Thoracic Society, all rights reserved. Listen to pronunciation.
Paratracheal lymph nodes - Wikipedia Semin Nucl Med 2002;32:293-321.
Paratracheal Lymph Nodes: Definition, Location - Verywell Health Sixty of the 90 patients had normal-sized and 30 had enlarged (>15 mm diameter) subcarinal lymph nodes on CT. Other, less common diseases such as lymphocytic interstitial pnuemonitis and Langerhans histiocytosis can present this way as well. Mediastinal lymph nodes are typically the first ones where cancer cells from the lungs will travel, and this is why they can be examined to determine whether cancer is spreading. Douglas A. Nelson, MD, is a board-certified oncologist and hematologist who previously served for 13 years as a physician in the US Air Force. The differential of this category is broader than the other two, and breaking it down further into nodules with a tree-in-bud appearance versus those with a more ground-glass appearance can be helpful. Increased risk for cancer following sarcoidosis.
Pretracheal lymph nodes - Wikipedia Given the large number of biopsies with no evidence of recurrence, this is somewhat less likely. Adenopathy is any disease or inflammation that involves glandular tissue or lymph nodes. How accurate is CT in predicting mediastinal invasion? Normal lymph nodes may show some increase in attenuation after intravenous contrast medium infusion. Secondary pulmonary lobule: normal and abnormal CT appearance. Lymphadenopathy by itself may simply means a virus is present, or it may be an indicator of something more serious and might require further testing. They may be involved in a variety of diseases, notably lymphoma, but their involvement in lung cancer is less common. Medical information provided on this website scrutinized to assure accuracy. Sarcoidosis: analysis of cells obtained by bronchial lavage. Lymph nodes are generally visible as discrete opacities, round or elliptical in shape, of soft-tissue attenuation, surrounded by mediastinal fat, and distinguishable from vessels by their location. The location and number of lymph nodes involved is an important aspect of cancer staging. Hilar lymph nodes are those located around the entrance to each lung on its medial side; the bronchi and pulmonary blood and lymphatic vessels enter and leave the lung through this . 2. In the absence of a known disease, an enlarged node must be regarded as likely hyperplastic or reactive. Together with the paraesophageal nodes, they drain the medial lower lobes, esophagus, pericardium, and posterior diaphragm.
Staging of Non-Small-Cell Lung Cancer - Pulmonology Advisor Dr. Arun Phophalia. Standard 18F-FDG-PET scanning was unable to differentiate between lung cancer and sarcoid. Chest 2007;131:1019-1027. no left pulmonary nodule or mass is identified. Hilar lymph nodes are further restricted to those that are adjacent to the main-stem bronchi. However, the less common conditions are malignant pleural mesothelioma and thymic epithelial tumor. N2 lymph nodes are considered potentially resectable (although this is not always the case). American Society of Clinical Oncology. Yeager H Jr, Williams MC, Beekman JF et al. Several numerical systems have been proposed for identifying the specific locations of intrathoracic lymph nodes (i.e., lymph node stations ), primarily for the purpose of lung cancer staging. Other important findings in staging lung cancer are discussed in other chapters. We offer this Site AS IS and without any warranties. Historically, a size cut-off of 10 mm short-axis diameter was employed. Health Effects of Cigarette Smoking. The left upper lobe is drained by this node group. In addition, the IASLC system includes the supraclavicular zone (right and left supraclavicular lymph nodes), the hilar/interlobar zone (hilar lymph nodes), and the peripheral zone (lobar, segmental and subsegmental nodes). 13.3 ). Lung diseases (e.g., lung cancer, sarcoidosis, tuberculosis, and fungal infections) that secondarily involve lymph nodes typically involve middle mediastinal lymph nodes. // ]]> Palpable supraclavicular, iliac, or popliteal nodes of any size and epitrochlear nodes larger than 5 mm are considered abnormal. Calcification of hilar and mediastinal lymph nodes is seen in 40% to . However, in the presence of inflammation or neoplastic infiltration, abnormal nodes can be matted together, giving the appearance of a single large mass or resulting in infiltration and replacement of mediastinal fat by soft-tissue opacity. I did aGallium 68 Dotanoc scan for locating any possible NETs. The patient performed also an acquisition of the lower extremities, for the evaluation Lymph node enlargement in a patient with sarcoidosis. Arch Int Med 1978;138:907-908. Mediastinal lymph nodes are lymph nodes located in the mediastinum. There are many different causes of mediastinal lymphadenopathy. 2009;4 (5): 568-77. Their use or mentioning on this website is only for informational purposes.
Where is the pericardial lymph node? - Studybuff 1. This type of cancer is most often found in men between the ages of 50 and 70 who smoke. Thank you, {{form.email}}, for signing up. They're very common. Privacy Statement | Term of Use | COI Conference Code of Conduct, Mediastinal Lymphadenopathy and Interstitial Lung Disease in a Cancer Patient. A 1.4 cm percarinal lymph node has measured metabolic activity up to 5.8 suv's. no right hilar adenopathy is seen. They drain into the deep cervical lymph nodes on the right and the thoracic duct on the left.. References A lymph node may swell if there is an infection present in the body. Roethe et al (24) performed one of the earliest studies evaluating the yield of transbronchial biopsy in sarcoid patients. Mediastinal lymph nodes larger than 2 cm are often involved by tumor, although large lymph nodes may also be seen in patients with sarcoidosis or other granulomatous diseases. What Is the Treatment for Presbyesophagus? Followed by a ct scan which revealed "A small precaarinal lymph node is seen of uncertain significance"Does that indicate precancer or what?. document.getElementById( "ak_js" ).setAttribute( "value", ( new Date() ).getTime() ); Please subscribe to our email newsletter: All brands, trademarks, service marks, logos, product labels and packing images displayed on this website, are registered to the respective owner. abuts 2R, inferior border: superior border of the left main pulmonary artery, lymph nodes anterior to the tracheal bifurcation are inferior to the above anatomic definitions and are thus technically unclassified by IASLC, these nodes are in the mediastinum (N2) and their surgical management mirrors that of 4R/4L lymph nodes, hence, pre-carinal nodes are best classified as part of the 4R/4L stations, superior border: inferior border of the aortic arch, superior border: line tangential to the upper border of the aortic arch, inferior border: lower border of the aortic arch, superior border: station 7, i.e. precarinal space: a potential space bounded by the ascending aorta anteriorly, the tracheal bifurcation posteriorly, the left pulmonary artery to the left, and the right pulmonary artery to the right. enlarged lymph nodes for more than two weeks, redness or inflamed skin over enlarged nodes. The causes of both kinds of lymphoma include genetic mutations, chronic infections, autoimmune diseases, changes in the immune system, immune deficiencies. Thank you, {{form.email}}, for signing up. The relatively low specificity of bronchoalveolar lavage fluid makes it less useful than other tests in achieving a diagnosis. Lung cancer can invade the mediastinum by direct extension, resulting in a mediastinal mass contiguous with the primary tumor. 2023 Dotdash Media, Inc. All rights reserved. Never disregard the medical advice of your physician or health professional, or delay in seeking such advice, because of something you read on this Site. On physical examination, the patient was afebrile with a normal blood pressure and pulse. had a ct scan of chest following a chest xray. {"url":"/signup-modal-props.json?lang=us"}, Luijkx T, Deng F, Bell D, et al. In a study evaluating its use in sarcoid, transbronchial needle aspiration successfully allowed a diagnosis of sarcoid in 72% of 32 patients presenting with stage I disease. without invasion proximal to a lobar bronchus (i.e., not involving a main bronchus), larger than 3 cm and less than or equal to 5 cm in greatest diameter a, involves a main bronchus without involving the carina a, associated with atelectasis or obstructive pneumonia, extending to the hilum, and involving part of or the entire lung a, larger than 5 cm and less than or equal to 7 cm in greatest diameter a, associated with separate tumor nodule(s) in the same lobe, invades parietal pleura, chest wall, phrenic nerve, or parietal pericardium a, invasion of the diaphragm, mediastinum, heart, great vessels, trachea, carina, recurrent laryngeal nerve, esophagus, or vertebral body, separate tumor nodule(s) in an ipsilateral lobe different from that of the primary tumor, tumor with pleural nodules or malignant pleural or pericardial effusion (pleural effusion not obviously associated with metastases has no effect on stage). Hilar lymph nodes are further restricted to those that are adjacent to the main-stem bronchi. In the absence of metastases (M1aM1c), the following rules apply: N0 or N1 nodes, depending on the primary tumor, may be part of stage I, II, or IIIa. Tree-in-bud refers to branches that can come off the nodules, giving them this appearance (4). 4.11 ) include: replacement of mediastinal fat by tumor (i.e., soft tissue); compression, displacement, or obstruction of mediastinal structures; extensive contact of tumor with a mediastinal structure, such as the aorta or trachea (e.g., one-quarter or more of its circumference); obliteration of the fat planes normally seen adjacent to mediastinal structures; pericardial thickening associated with a mass. Ascending or descending colon and . 4.10 ). 4.1, 4.3, and 4.4A ).