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36-416: A third of all people with a thymoma have symptoms caused by compression of the surrounding organs by an expansive mass. These problems may take the form of superior vena cava syndrome , dysphagia (difficulty swallowing), cough , or chest pain . One-third of patients have their tumors discovered because they have an associated autoimmune disorder . As mentioned earlier, the most common of those conditions

72-419: A half years. This relates to the cancerous causes of SVC found in 90% of cases. The average age of disease onset is 54 years. Immune deficiency Immunodeficiency , also known as immunocompromisation , is a state in which the immune system 's ability to fight infectious diseases and cancer is compromised or entirely absent. Most cases are acquired ("secondary") due to extrinsic factors that affect

108-405: A pathological process or by a deep vein thrombosis in the vein itself, although this latter is less common (approximately 35% due to the use of intravascular devices). The main techniques of diagnosing SVCS are with chest X-rays (CXR), CT scans , transbronchial needle aspiration at bronchoscopy and mediastinoscopy . CXRs often provide the ability to show mediastinal widening and may show

144-736: A patient require assistance with respiration whether it be by bag/valve/mask, bilevel positive airway pressure (BiPAP), continuous positive airway pressure (CPAP) or mechanical ventilation, extreme care should be taken. Increased airway pressure will tend to further compress an already compromised SVC and reduce venous return and in turn cardiac output and cerebral and coronary blood flow. Spontaneous respiration should be allowed during endotracheal intubation until sedation allows placement of an ET tube and reduced airway pressures should be employed when possible. Symptoms are usually relieved with radiation therapy within one month of treatment. However, even with treatment, 99% of patients die within two and

180-431: Is common variable immunodeficiency (CVID) where multiple autoimmune diseases are seen, e.g., inflammatory bowel disease , autoimmune thrombocytopenia , and autoimmune thyroid disease. Familial hemophagocytic lymphohistiocytosis , an autosomal recessive primary immunodeficiency, is another example. Low blood levels of red blood cells, white blood cells, and platelets , rashes, lymph node enlargement , and enlargement of

216-872: Is myasthenia gravis (MG); 10–15% of patients with MG have a thymoma and, conversely, 30–45% of patients with thymomas have MG. Additional associated autoimmune conditions include thymoma-associated multiorgan autoimmunity , pure red cell aplasia and Good syndrome (thymoma with combined immunodeficiency and hypogammaglobulinemia ). Other reported disease associations are with acute pericarditis , agranulocytosis , alopecia areata , ulcerative colitis , Cushing's disease , hemolytic anemia , limbic encephalopathy , myocarditis , nephrotic syndrome , panhypopituitarism , pernicious anemia , polymyositis , rheumatoid arthritis , sarcoidosis , scleroderma , sensorimotor radiculopathy, stiff person syndrome , systemic lupus erythematosus and thyroiditis . One-third to one-half of all persons with thymoma have no symptoms at all, and

252-580: Is a commonly used method which captures the majority of coding regions of the genome for sequencing, as these regions contain the majority of disease-causing mutations Useful for identifying mutations in specific genes • Trio or Whole-Family Analyses: In some cases, analyzing the DNA of the patient, parents, and siblings (trio analysis) or the entire family (whole-family analysis) can reveal inheritance patterns and identify causative mutations Available treatment falls into two modalities: treating infections and boosting

288-1194: Is also known as congenital immunodeficiencies. Many of these disorders are hereditary and are autosomal recessive or X-linked . There are over 95 recognised primary immunodeficiency syndromes; they are generally grouped by the part of the immune system that is malfunctioning, such as lymphocytes or granulocytes . The treatment of primary immunodeficiencies depends on the nature of the defect, and may involve antibody infusions, long-term antibiotics and (in some cases) stem cell transplantation . The characteristics of lacking and/or impaired antibody functions can be related to illnesses such as X-Linked Agammaglobulinemia and Common Variable Immune Deficiency Secondary immunodeficiencies, also known as acquired immunodeficiencies, can result from various immunosuppressive agents, for example, malnutrition , aging , particular medications (e.g., chemotherapy , disease-modifying antirheumatic drugs , immunosuppressive drugs after organ transplants , glucocorticoids ) and environmental toxins like mercury and other heavy metals , pesticides and petrochemicals like styrene , dichlorobenzene , xylene , and ethylphenol . For medications,

324-1119: Is also sometimes associated with the development of autoimmune and atopic phenomena. Medical History and Physical Examination: A physician will inquire about past illnesses and family history of immune disorders to identify inherited conditions. A detailed physical examination helps recognize symptoms indicative of an immune disorder. Blood Tests: these tests are instrumental in diagnosing immunodeficiency as they measure: Infection-fighting proteins (immunoglobulins): Essential for robust immune defense, these protein levels are measured to evaluate immune function. Blood cell counts: Deviations in specific blood cells can point to an immune system anomaly. Immune system cells: These assessments are used to measure

360-592: Is also the hallmark of acquired immunodeficiency syndrome (AIDS), caused by the human immunodeficiency virus (HIV). HIV directly infects a small number of T helper cells , and also impairs other immune system responses indirectly. Various hormonal and metabolic disorders can also result in immune deficiency including anemia, hypothyroidism and hyperglycemia. Smoking, alcoholism and drug abuse also depress immune response. Heavy schedules of training and competition in athletes increases their risk of immune deficiencies. The cause of immunodeficiency varies depending on

396-405: Is directly related to the treatment of the underlying compression. Shortness of breath is the most common symptom, followed by face or arm swelling. Following are frequent symptoms: Superior vena cava syndrome usually presents more gradually with an increase in symptoms over time as malignancies increase in size or invasiveness. Over 80% of cases are caused by malignant tumors compressing

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432-471: Is in the 40s and 50s, though the age may range from six years to 83 years. Superior vena cava syndrome Superior vena cava syndrome ( SVCS ), is a group of symptoms caused by obstruction of the superior vena cava ("SVC"), a short, wide vessel carrying circulating blood into the heart. The majority of cases are caused by malignant tumors within the mediastinum , most commonly lung cancer and non-Hodgkin's lymphoma , directly compressing or invading

468-491: Is primary) and acquired immune deficiency syndrome (which is secondary). B cell deficiency The distinction between primary versus secondary immunodeficiencies is based on, respectively, whether the cause originates in the immune system itself or is, in turn, due to insufficiency of a supporting component of it or an external decreasing factor of it. A number of rare diseases feature a heightened susceptibility to infections from childhood onward. Primary Immunodeficiency

504-568: Is said to be immunocompromised . An immunocompromised individual may particularly be vulnerable to opportunistic infections , in addition to normal infections that could affect anyone. It also decreases cancer immunosurveillance , in which the immune system scans the body's cells and kills neoplastic ones. They are also more susceptible to infectious diseases owing to the reduced protection afforded by vaccines . In reality, immunodeficiency often affects multiple components, with notable examples including severe combined immunodeficiency (which

540-442: Is thought to be less benign. When a thymoma is suspected, a CT/CAT scan is generally performed to estimate the size and extent of the tumor, and the lesion is sampled with a CT-guided needle biopsy . Increased vascular enhancement on CT scans can be indicative of malignancy, as can be pleural deposits. Limited biopsies are associated with a very small risk of pneumomediastinum or mediastinitis and an even-lower risk of damaging

576-418: Is widely recognized as the benchmark method for accurately identifying individual nucleotide changes, as well as small-scale insertions or deletions in DNA. It is particularly valuable for confirming known familial genetic variations, for validating findings from next-generation sequencing technologies, and in specific scenarios that require sequencing of single genes. An example is its use to confirm mutations in

612-408: The acetylcholine receptor (indicative of myasthenia), electrolytes , liver enzymes and renal function . The Masaoka Staging System is used widely and is based on the anatomic extent of disease at the time of surgery: Surgery is the mainstay of treatment for thymoma. If the tumor is apparently invasive and large, preoperative (neoadjuvant) chemotherapy and/or radiotherapy may be used to decrease

648-506: The heart or large blood vessels. Sometimes thymoma metastasize for instance to the abdomen. The diagnosis is made via histologic examination by a pathologist, after obtaining a tissue sample of the mass. Final tumor classification and staging is accomplished pathologically after formal surgical removal of the thymic tumor. Selected laboratory tests can be used to look for associated problems or possible tumor spread. These include: full blood count , protein electrophoresis , antibodies to

684-465: The Bruton tyrosine kinase (BTK) gene, which are linked to X-linked agammaglobulinemia (XLA) • Targeted Gene Sequencing Panels (tNGS): This technology is ideal for examining genes in specific pathways or for follow-up experiments (targeted resequencing) from whole genome sequencing (WGS). It is rapid and more cost-effective than WGS, and because it allows for deeper sequencing. • Whole Exome Sequencing (WES):

720-485: The SVC wall. Non-malignant causes are increasing in prevalence due to expanding use of intravascular devices (such as permanent central venous catheters and leads for pacemakers and defibrillators ), which can result in thrombosis . Other non-malignant causes include benign mediastinal tumors, aortic aneurysm , infections, and fibrosing mediastinitis . Characteristic features are edema (swelling due to excess fluid) of

756-570: The face and arms and development of swollen collateral veins on the front of the chest wall . Shortness of breath and coughing are quite common symptoms; difficulty swallowing is reported in 11% of cases, headache in 6% and stridor (a high-pitched wheeze) in 4%. The symptoms are rarely life-threatening, though edema of the epiglottis can make breathing difficult, edema of the brain can cause reduced alertness, and in less than 5% of cases of SVCO, severe neurological symptoms or airway compromise are reported. Resolution of superior vena cava syndrome

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792-823: The gut and lungs are seen in chronic granulomatous disease (CGD) as well. CGD is caused by a decreased production of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase by neutrophils . Hypomorphic RAG mutations are seen in patients with midline granulomatous disease ; an autoimmune disorder that is commonly seen in patients with granulomatosis with polyangiitis and NK/T cell lymphomas. Wiskott–Aldrich syndrome (WAS) patients also present with eczema, autoimmune manifestations, recurrent bacterial infections and lymphoma. In autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) also autoimmunity and infections coexist: organ-specific autoimmune manifestations (e.g., hypoparathyroidism and adrenocortical failure) and chronic mucocutaneous candidiasis. Finally, IgA deficiency

828-516: The immune system. Prevention of Pneumocystis pneumonia using trimethoprim/sulfamethoxazole is useful in those who are immunocompromised. In the early 1950s Immunoglobulin(Ig) was used by doctors to treat patients with primary immunodeficiency through intramuscular injection. Ig replacement therapy are infusions that can be either subcutaneous or intravenously administered, resulting in higher Ig levels for about three to four weeks, although this varies with each patient. Prognosis depends greatly on

864-467: The inflammatory response to tumor invasion and edema surrounding the tumor. Glucocorticoids are most helpful if the tumor is steroid-responsive, such as lymphomas. In addition, diuretics (such as furosemide ) are used to reduce venous return to the heart which relieves the increased pressure. In an acute setting, endovascular stenting by an interventional radiologist may provide relief of symptoms in as little as 12–24 hours with minimal risks. Should

900-490: The levels of various immune cells. Genetic testing involves collecting samples from patients for molecular analysis when there is a suspicion of inborn errors in immunity. Most Primary Immunodeficiency Disorders (PIDs) are inherited as single-gene defects. The key genes associated with immunodeficiency diseases include CD40L, CD40, RAG1, RAG2, IL2RG, and ADA. Here is a summary of some methods utilized to identify genetic anomalies: Sanger Sequencing of Single Genes: Sanger sequencing

936-495: The liver and spleen are commonly seen in these patients. Presence of multiple uncleared viral infections due to lack of perforin are thought to be responsible. In addition to chronic and/or recurrent infections many autoimmune diseases including arthritis, autoimmune hemolytic anemia, scleroderma and type 1 diabetes are also seen in X-linked agammaglobulinemia (XLA). Recurrent bacterial and fungal infections and chronic inflammation of

972-644: The majority of cases also pleural recurrences can be removed. Recently, surgical removal of pleural recurrences can be followed by hyperthermic intrathoracic perfusion chemotherapy or intrathoracic hyperthermic perfused chemotherapy (ITH) . Prognosis is much worse for stage III or IV thymomas as compared with stage I and II tumors. Invasive thymomas uncommonly can also metastasize , generally to pleura , bones , liver or brain in approximately 7% of cases. A study found that slightly over 40% of observed patients with stage III and IV tumors survived for at least 10 years after diagnosis. The median age of these patients at

1008-674: The mass is identified on a chest X-ray or CT/CAT scan performed for an unrelated problem. Thymoma originates from the epithelial cell population in the thymus, and several microscopic subtypes are now recognized. There are three principal histological types of thymoma, depending on the appearance of the cells by microscopy: Thymic cortical epithelial cells have abundant cytoplasm, vesicular nucleus with finely divided chromatin and small nucleoli and cytoplasmic filaments contact adjacent cells. Thymic medullary epithelial cells in contrast are spindle shaped with oval dense nucleus and scant cytoplasm thymoma if recapitulates cortical cell features more,

1044-409: The nature and severity of the condition. Some deficiencies cause early mortality (before age one), others with or even without treatment are lifelong conditions that cause little mortality or morbidity. Newer stem cell transplant technologies may lead to gene based treatments of debilitating and fatal genetic immune deficiencies. Prognosis of acquired immune deficiencies depends on avoiding or treating

1080-486: The nature of the disorder. The cause can be either genetic or acquired by malnutrition and poor sanitary conditions. Only for some genetic causes, the exact genes are known. There are a large number of immunodeficiency syndromes that present clinical and laboratory characteristics of autoimmunity. The decreased ability of the immune system to clear infections in these patients may be responsible for causing autoimmunity through perpetual immune system activation. One example

1116-690: The patient's immune system. Examples of these extrinsic factors include HIV infection and environmental factors , such as nutrition . Immunocompromisation may also be due to genetic diseases /flaws such as SCID . In clinical settings, immunosuppression by some drugs, such as steroids, can either be an adverse effect or the intended purpose of the treatment. Examples of such use is in organ transplant surgery as an anti- rejection measure and in patients with an overactive immune system, as in autoimmune diseases . Some people are born with intrinsic defects in their immune system , or primary immunodeficiency . A person who has an immunodeficiency of any kind

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1152-473: The presenting primary cause of SVCS. However, 16% of people with SVC syndrome have a normal chest X-ray. CT scans should be contrast enhanced and be taken on the neck, chest, lower abdomen, and pelvis. They may also show the underlying cause and the extent to which the disease has progressed. Several methods of treatment are available, mainly consisting of careful drug therapy and surgery. Glucocorticoids (such as prednisone or methylprednisolone ) decrease

1188-603: The size and improve resectability, before surgery is attempted. When the tumor is an early stage (Masaoka I through IIB), no further therapy is necessary. Removal of the thymus in adults does not appear to induce immune deficiency . In children, however, postoperative immunity may be abnormal and vaccinations for several infectious agents are recommended. Invasive thymomas may require additional treatment with radiotherapy and chemotherapy ( cyclophosphamide , doxorubicin and cisplatin ).. Recurrences of thymoma are described in 10-30% of cases up to 10 years after surgical resection, and in

1224-487: The superior vena cava. Lung cancer , usually small cell carcinoma , comprises 75–80% of these cases and non-Hodgkin lymphoma , most commonly diffuse large B-cell lymphoma , comprises 10–15%. Rare malignant causes include Hodgkin's lymphoma , metastatic cancers, leukemia , leiomyosarcoma of the mediastinal vessels, and plasmocytoma . Syphilis and tuberculosis have also been known to cause superior vena cava syndrome. SVCS can be caused by invasion or compression by

1260-518: The term immunosuppression generally refers to both beneficial and potential adverse effects of decreasing the function of the immune system, while the term immunodeficiency generally refers solely to the adverse effect of increased risk for infection. Many specific diseases directly or indirectly cause immunosuppression. This includes many types of cancer , particularly those of the bone marrow and blood cells ( leukemia , lymphoma , multiple myeloma ), and certain chronic infections. Immunodeficiency

1296-464: The time of thymoma diagnosis was 57 years. Patients who have undergone thymectomy for thymoma should be warned of possible severe side effects after yellow fever vaccination. This is probably caused by inadequate T-cell response to live attenuated yellow fever vaccine. Deaths have been reported. The incidence of thymomas is around 0.13-0.26 per 100,000 people per year. Males are affected slightly less frequently than females. The typical age at diagnosis

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