Junker K, Krismann M.

Zentrum für Pathologie, Klinikum Bremen-Mitte, Bremen. klaus.junker@klinikum-bremen-mitte.de

Abstract

In the WHO classification, pleural tumours of mesothelial and mesenchymal origin as well as lymphoproliferative disorders are distinguished, with malignant mesotheliomas forming the most common primary pleural tumour. Histologically, a prognostically relevant differentiation between epitheloid (40-60 %), sarcomatoid (20-30 %), and biphasic mesotheliomas (20-30 %) is made. Besides other rare primary tumours of the pleura, the differential diagnoses of malignant mesotheliomas comprise carcinomatous pleuritis of intra- and extrapulmonary malignancies. Especially in early tumour stages, the differentiation from reactive pleural changes requires a close interdisciplinary cooperation with a careful correlation between histopathological findings and clinical presentation.

Keywords: malignant pleural mesothelioma – carcinomatous pleuritis – solitary fibrous tumour of the pleura – WHO classification

Glossary

pleura

(pler-uh) the membrane around the lungs and lining of the chest cavity. (Pleural mesothelioma.)

differentiation

(dif-er-en-she-A-shun) the normal process through which cells mature so they can carry out the jobs they were meant to do. Cancer cells are poorly differentiated.

mesothelioma

a tumor derived from mesothelial tissue, such as the peritoneum (lining the abdomen) or pleura (lining the lungs). More on mesothelioma.

Yildirim H, Metıntaş M, Ak G, Dündar E, Ergınel S.

Department of Chest Diseases, Faculty of Medicine, Osmangazi University, Eskişehir, Turkey. heylul2002@yahoo.com.

Abstract

Almost all cancers can cause distant pleural metastases. However, pleural metastases of soft tissue sarcoma that constitute less than 1% of adult solid malignancy are extremely rare. It is very difficult to distinguish them form sarcomatous malignant mesothelioma on histopathological features. We report a 57 year-old man who presented to us with left chest pain and progressive dyspnea and was diagnosed to have a pleural metastases of soft tissue sarcoma by thoracoscopic biopsy.

Glossary

sarcoma

(sar-co-muh) a malignant tumor growing from connective tissues, such as cartilage, fat, muscle, or bone.

biopsy

(buy-op-see) the removal of a sample of tissue to see whether cancer cells are present. There are several kinds of biopsies. In some, a very thin needle is used to draw fluid and cells from a lump. In a core biopsy, a larger needle is used to remove more tissue.

tissue

a collection of cells, united to perform a particular function.

mesothelioma

a tumor derived from mesothelial tissue, such as the peritoneum (lining the abdomen) or pleura (lining the lungs). More on mesothelioma.

Hjerpe A, Dobra K.

Department of Laboratory Medicine, Division of Pathology, Karolinska Institutet, Stockholm, Sweden.

Abstract

Malignant mesothelioma (MM) is a connective tissue tumor with partial epithelioid differentiation. The pattern of proteoglycan (PG) expression by epithelioid and fibroblast-like (sarcomatoid) MM cells differ; cell surface PGs being more abundant in the former phenotype and matrix PGs in the latter. The differentiation as well as much of the malignant nature of these tumors is dependent on the expression of surface PGs. The syndecans, however, also translocate to the nucleus for an as yet unknown function.

Glossary

nucleus

(new-clee-us) the center of a cell where the DNA is housed and replicated. Studying the size and shape of a cell's nucleus under the microscope can help pathologists distinguish cancer cells from benign cells.

differentiation

(dif-er-en-she-A-shun) the normal process through which cells mature so they can carry out the jobs they were meant to do. Cancer cells are poorly differentiated.

cell

the basic unit of which all living things are made. Cells replace themselves by splitting and forming new cells (mitosis). The processes that control the formation of new cells and the death of old cells are disrupted in cancer.

tissue

a collection of cells, united to perform a particular function.

tumor

an abnormal lump or mass of tissue. Tumors can be benign (not cancerous) or malignant (cancerous).

mesothelioma

a tumor derived from mesothelial tissue, such as the peritoneum (lining the abdomen) or pleura (lining the lungs). More on mesothelioma.

Neragi-Miandoab S, Richards WG, Sugarbaker DJ.

Department of Surgery, Cardiothoracic Surgery, Boston University Medical Center, School of Medicine, One Boston Medical Center Place, Boston MA 02118, United States.

Abstract

Aim: The survival of patients with malignant pleural mesothelioma (MPM) who do not seek treatment ranges from 4 to 12 months. To date, the optimal procedure for resection of malignant pleural mesothelioma is controversial, extrapleural pneumonectomy has been most consistently associated with long-term survival and has provided the most radical cytoreduction; but, unfortunately, not all patients qualify for this invasive surgical approach.

Methods: Between 1992 and 2000, 64 patients underwent pleurectomy as a palliative treatment for MPM. This retrospective study evaluates the operative outcome and the impact of some prognostic factors on patients’ survival. Preoperative evaluation included chest X-ray, CT and/or MRI. Diagnosis was made by pleural biopsy via needle, open, or VATS biopsy. The Kaplan-Meier curve and the Log-Rank test were used to analyze the data.

Results: The median age of the study group was 65 (with a range of 29-84 years). Thirty-six patients had epithelial histology, and 28 patients had sarcomatoid or mixed type (e.g., epithelial+spindle, epithelial+sarcomatoid). The 30-day mortality rate was 3.1%. The overall survival rate was 43%, 28%, and 10% at 1, 2, and 3 years, respectively. The overall median survival was 9.4 months (ranging from 1.15 to 52.7 months). The overall median survival with epithelial histology (n=36, 56%) was 21.7 months (with a range of 1.4-52.7 months) versus 5.8 months (with a range of 1.15-18.3 months) for the sarcomatoid or mixed type (n=28, 44%), p=0.0001. The morbidity included atrial fibrillation (n=5), wound infection (n=2), prolonged intubation (longer than 24h, n=8), reintubation for respiratory failure (n=2), pulmonary emboli (n=1), UTI (n=16), DVT (n=5), MI (n=4), and postoperative bleeding (n=7). Univariant analysis demonstrated that the only prognostic factors influencing survival in our series was the histologic type. Age, gender, and the affected side of the lung did not affect the median survival.

Conclusion: Our results show that pleurectomy can be performed as a means of palliation for advanced-stage disease with a low mortality rate and may, in fact, improve survival in patients with epithelial subtype as compared with historical controls in the literature with no surgical intervention.

Glossary

survival rate

the percentage of survivors with no trace of disease within a certain period of time after diagnosis or treatment. For cancer, a 5-year survival rate is often given. This does not mean that people can't live more than five years, or that those who live for 5 years are necessarily permanently cured.

resection

surgery to remove part or all of an organ or other structure.

morbidity

a measure of the new cases of a disease in a population; the number of people who have a disease.

mortality

a measure of the rate of death from a disease within a given population.

MRI

Stands for magnetic resonance imaging. A method of taking pictures of the inside of the body. Instead of using x-rays, MRI uses a powerful magnet and transmits radio waves through the body; the images appear on a computer screen as well as on film. Like x-rays, the procedure is physically painless, but some people find it psychologically uncomfortable to be in the small core of the MRI machine.

diagnosis

identifying a disease by its signs or symptoms, and by using imaging procedures and laboratory findings. The earlier a diagnosis of cancer is made, the better the chance for long-term survival.

biopsy

(buy-op-see) the removal of a sample of tissue to see whether cancer cells are present. There are several kinds of biopsies. In some, a very thin needle is used to draw fluid and cells from a lump. In a core biopsy, a larger needle is used to remove more tissue.

mesothelioma

a tumor derived from mesothelial tissue, such as the peritoneum (lining the abdomen) or pleura (lining the lungs). More on mesothelioma.

extrapleural pneumonectomy

(EPP) surgery to remove the pleura, diaphragm, pericardium, and entire lung involved with the tumor. You can view a web cast from Brigham and Women's Hospital in Boston of this procedure being done by Dr. David Sugarbaker: see the extrapleural pneumonectomy (EPP) web cast here.

Klebe S, Mahar A, Henderson DW, Roggli VL.

Department of Anatomical Pathology, Flinders University of South Australia, Adelaide, SA, Australia.

Abstract

Only a small number of malignant mesotheliomas with heterologous elements have been described. There are currently no criteria for diagnosis and little data regarding prognosis. We suggest that the term heterologous mesothelioma should be reserved for tumours that show malignant heterologous elements, notably osteosarcomatous, chondrosarcomatous, or rhabdomyoblastic elements but have immunohistochemical and clinical characteristics of mesothelioma. We identified 27 such cases and characterized the clinical and pathological characteristics of these tumours. In our series, 89% originated in the pleura, and 11% from the peritoneal cavity. The median age at diagnosis was 68 years, ranging from 27 to 85 years. Of these cases, 93% occurred in males and 7% in women. Of the 27 mesothelioma cases 16 (59%) were sarcomatoid, 10 (37%) were biphasic, and one was reported as epithelioid; 40% (11 cases) showed osteosarcomatous elements only, 19% showed areas of rhabdomyosarcoma only, 19% contained areas of chondrosarcoma only, and 22% exhibited osteochondromatous elements. Immunohistochemical labelling for cytokeratins was present in the majority of cases. Exposure to asbestos was identified in all the 17 cases for which an exposure history was available (63%). Median survival was 6 months after diagnosis, similar to the survival seen in sarcomatoid mesotheliomas. The differential diagnosis includes primary and secondary pleural sarcomas, including osteosarcomas and chondrosarcomas. Immunohistochemical labelling for cytokeratins is helpful in the distinction, but lack of labelling for cytokeratins in a spindle cell/sarcomatoid tumour does not exclude the diagnosis of mesothelioma, irrespective of the presence of heterologous elements. We suggest that if the anatomical distribution conforms to that of mesothelioma, a diagnosis of heterologous mesothelioma should be made in preference to a diagnosis of primary pleural osteosarcoma or chondrosarcoma, regardless of cytokeratin positivity, as for conventional non-heterologous sarcomatoid mesothelioma.

Glossary

prognosis

(prog-no-sis) a prediction of the course of disease; the outlook for the cure of the patient. For example, women with breast cancer that was detected early and who received prompt treatment have a good prognosis.

pleura

(pler-uh) the membrane around the lungs and lining of the chest cavity. (Pleural mesothelioma.)

diagnosis

identifying a disease by its signs or symptoms, and by using imaging procedures and laboratory findings. The earlier a diagnosis of cancer is made, the better the chance for long-term survival.

cell

the basic unit of which all living things are made. Cells replace themselves by splitting and forming new cells (mitosis). The processes that control the formation of new cells and the death of old cells are disrupted in cancer.

mesothelioma

a tumor derived from mesothelial tissue, such as the peritoneum (lining the abdomen) or pleura (lining the lungs). More on mesothelioma.

peritoneal

(pair-uh-tuh-nee-al) the serous membrane that lines the cavity of the abdomen. (More on Peritoneal Mesothelioma.)

Yamazaki M, Ohwada A, Miyaji A, Yamazaki H, Nara T, Hirai S, Fujii H, Uekusa T, Suzuki M, Iwase A, Takahashi K.

Department of Respiratory Medicine, Juntendo Tokyo Koto Geriatric Medical Center, Tokyo. mariko@med.juntendo.ac.jp

Abstract

A 72-year-old man patient was referred to our institution for evaluation and treatment of right pleural effusion. Eosinophilic pleural effusion and peripheral eosinophilia were identified during the course of hospitalization. Pulmonary paragonimiasis was confirmed by the presence of paragonimus-specific IgG antibodies for Paragonimus (P.) westermani and P. miyazakii in his serum. Although Praziquantel, a highly effective agent for the treatment of lung flukes was repeatedly administered, the pleural effusion did not subside and the patient’s condition gradually deteriorated until his death due to circulatory insufficiency. Postmortem examination revealed malignant mesothelioma of the sarcomatous type encasing the right lung and heart. Cardiac involvement accompanied with old and recent-onset myocardial ischemic changes resulted in death of this patient. Here, we report a very rare case of malignant mesothelioma with a concomitant infection of parasitic lung fluke.

Keywords: paragonimiasis, malignant mesothelioma, eosinophilia

Glossary

mesothelioma

a tumor derived from mesothelial tissue, such as the peritoneum (lining the abdomen) or pleura (lining the lungs). More on mesothelioma.

pleural effusion

an abnormal accumulation of fluid, usually caused by trauma or disease, in the pleural space.

Moran CA, Albores-Saavedra J, Suster S.

Department of Pathology, M D Anderson Cancer Center, Houston, TX 77030, USA. cesarmoran@mdanderson.org

Abstract

Aims: To present eight cases of primary diffuse peritoneal malignant mesothelioma in children <15 years old, with a discussion of the pitfalls of this diagnosis in the paediatric age group.

Methods and Results: The cases were selected based on the following criteria: (i) primary peritoneal neoplasms confined grossly or radiographically to the abdominal cavity; (ii) negative history of previous or another associated malignancy; (iii) histopathological confirmation. All patients (five female, three male) presented clinically with symptoms of abdominal pain, distention and ascites. Grossly, the tumours showed multiple, diffuse peritoneal nodules. Histologically, seven cases corresponded to epithelioid mesotheliomas and one case displayed biphasic (epithelioid and spindle) cellular proliferation. Immunohistochemical studies for cytokeratin (CK) 5/6, calretinin and low-molecular-weight CK (CAM5.2) showed strong cytoplasmic positivity in the neoplastic cells. Three patients were treated by chemotherapy. On clinical follow-up, four patients with epithelioid mesotheliomas were alive and well from 12 to 18 months after initial diagnosis; one patient with a mixed (biphasic epithelioid/sarcomatoid) mesothelioma died of tumour 24 months after diagnosis.

Conclusions: Peritoneal malignant mesothelioma in children is a rare condition that can introduce difficulties in histopathological diagnosis.

Glossary

diagnosis

identifying a disease by its signs or symptoms, and by using imaging procedures and laboratory findings. The earlier a diagnosis of cancer is made, the better the chance for long-term survival.

chemotherapy

(key-mo-THER-uh-pee) treatment with drugs to destroy cancer cells. Chemotherapy is often used with surgery or radiation to treat cancer when the cancer has spread, when it has come back (recurred), or when there is a strong chance that it could recur.

cancer

malignancy; a group of diseases typified by abnormal, generally out-of-control, cell growth.

mesothelioma

a tumor derived from mesothelial tissue, such as the peritoneum (lining the abdomen) or pleura (lining the lungs). More on mesothelioma.

peritoneal

(pair-uh-tuh-nee-al) the serous membrane that lines the cavity of the abdomen. (More on Peritoneal Mesothelioma.)

ascites

(uh-sigh-tees) excess fluid accumulation in the abdominal (peritoneal) cavity.

Batirel HF, Metintas M, Caglar HB, Yildizeli B, Lacin T, Bostanci K, Akgul AG, Evman S, Yuksel M.

Marmara University Hospital, Department of Thoracic Surgery, Istanbul, Turkey. hbatirel@marmara.edu.tr

Abstract

Introduction: Multimodality treatment has achieved significant success in local control and treatment of early-stage malignant pleural mesothelioma patients. However, its favorable effect on survival is questionable.

Methods: We have instituted a trimodality treatment protocol consisting of extrapleural pneumonectomy, adjuvant high-dose (54 Gy) hemithoracic irradiation, and platin-based chemotherapy in a multi-institutional setting. Preoperative pulmonary function tests, echocardiogram, chest computed tomography, and magnetic resonance imaging scans were performed in all patients. Twenty patients have been treated with this protocol during 2003-2007. Seventeen had a history of environmental asbestos/erionite exposure. Clinical stages were T1-3N0-2.

Results: Median age was 56 (41-70, 8 female). There was one postoperative mortality (% 5) due to ARDS. Morbidity occurred in 11 patients (% 55). Histology was epithelial in 17, mixed in 2, and sarcomatoid in 1. Sixteen patients underwent extrapleural pneumonectomy. Microscopic margin positivity was present in 14 patients with macroscopic complete resection. Twelve patients completed all three treatments. Median follow-up was 16 months (1-43). Overall median survival was 17 months (24% at 2 years). Eight patients had extrapleural lymph node involvement (internal mammary [n = 3], subcarinal [n = 2], pulmonary ligament [n = 1], diaphragmatic [n = 1], subaortic [n = 1]). There was better survival in patients without lymph node metastasis (24 versus 13 months median survival, p = 0.052). Currently, 7 patients are alive, 6 without recurrence, and 2 patients at 40 and 45 months.

Conclusions: Trimodality treatment in malignant pleural mesothelioma seems to prolong survival in patients without lymph node metastasis. Novel techniques are needed for preoperative assessment of extrapleural lymph nodes.

Glossary

resection

surgery to remove part or all of an organ or other structure.

recurrence

cancer that has come back after treatment. Local recurrence is when the cancer comes back at the same place as the original cancer. Regional recurrence is when the cancer appears in the lymph nodes near the first site. Distant recurrence is when it appears in organs or tissues (such as the lungs, liver, bone marrow, or brain) farther from the original site than the regional lymph nodes. Metastasis means that the disease has recurred at a distant site.

protocol

(pro-teh-call) a formal outline or plan, such as a description of what treatments a patient will receive and exactly when each should be given.

oncology

(on-call-o-jee) the branch of medicine concerned with the diagnosis and treatment of cancer.

morbidity

a measure of the new cases of a disease in a population; the number of people who have a disease.

mortality

a measure of the rate of death from a disease within a given population.

metastasis

(meh-tas-teh-sis) the spread of cancer cells to distant areas of the body by way of the lymph system or bloodstream.

margin

edge of the tissue removed during surgery. A negative margin is a sign that no cancer was left behind. A positive margin indicates that cancer cells are found at the outer edge of tissue removed during surgery. It is usually a sign that some cancer remains in the body.

lymph nodes

small bean-shaped collections of immune system tissue such as lymphocytes, found along lymphatic vessels. They remove cell waste and fluids from lymph and help fight infections. Also called lymph glands.

lymph

(limf) clear fluid that flows through the lymphatic vessels and contains cells known as lymphocytes. These cells are important in fighting infections and may also have a role in fighting cancer.

imaging

any method used to produce a picture of internal body structures. Some imaging methods used to detect cancer are x-rays (including mammograms and CT scans), magnetic resonance imaging (MRI), scintigraphy, and ultrasound.

chemotherapy

(key-mo-THER-uh-pee) treatment with drugs to destroy cancer cells. Chemotherapy is often used with surgery or radiation to treat cancer when the cancer has spread, when it has come back (recurred), or when there is a strong chance that it could recur.

mesothelioma

a tumor derived from mesothelial tissue, such as the peritoneum (lining the abdomen) or pleura (lining the lungs). More on mesothelioma.

extrapleural pneumonectomy

(EPP) surgery to remove the pleura, diaphragm, pericardium, and entire lung involved with the tumor. You can view a web cast from Brigham and Women's Hospital in Boston of this procedure being done by Dr. David Sugarbaker: see the extrapleural pneumonectomy (EPP) web cast here.

Mineo TC, Ambrogi V, Pompeo E, Baldi A, Stella F, Aurea P, Marino M.

Department of Thoracic Surgery, Policlinico Tor Vergata University, Rome, Italy. mineo@med.uniroma2.it

Abstract

Background: The purpose of this study was to examine the prognostic impact of occult disease after extrapleural pneumonectomy for malignant mesothelioma.

Methods: We reviewed the resection margin and node specimens from 41 consecutive patients undergoing extrapleural pneumonectomy for malignant pleural mesothelioma in different institutions between 1985 and 2004. The specimens were reassessed by immunohistochemical staining with anticalretinin and antimesothelin monoclonal antibodies, and results were used to draw Kaplan–Meier survival curves and perform Cox regression analyses.

Results: Histologic examination showed 34 epithelioid, 4 biphasic, and 3 sarcomatoid subtypes. Results of postoperative TNM staging were that 14 patients were in stage I, 6 were in stage II, and 21 were in stage III. One patient died during the early postoperative period. Median survival was 13 months. Survival was affected by nonepithelial histologic type (p = 0.001), TNM stage (p = 0.007), positive resection margins (p = 0.002), and N disease (p = 0.01). Immunohistochemistry revealed occult positive resection margins in 6 patients, not correlated with T stage. Microscopic N disease was discovered in 5 patients, of whom 2 had their nodes retrieved through cervical mediastinoscopy. No correlation with nodal diameter was found. In all patients microscopic N disease could have been accessible through mediastinoscopy. Overall, the presence of occult disease was diagnosed in 5 new patients and influenced survival more than any other variable, both at univariate (p < 0.001) and multivariate Cox regression analysis (p < 0.0001; odds ratio, 5.4; 95% confidence interval, 3 to 15).

Conclusions: In malignant pleural mesothelioma, the presence of occult disease in resection margins and lymph nodes can be identified by immunohistochemistry and significantly influences the prognosis. Cervical mediastinoscopy is useful in all patients considered for radical resection, but all specimens should be processed with immunohistochemical staining.

Glossary

staging

the process of finding out whether cancer has spread and if so, how far. There is more than one system for staging. The TNM system, described below, is one used often. The TNM system for staging gives three key pieces of information: T refers to the size of the Tumor N describes how far the cancer has spread to nearby Nodes M shows whether the cancer has spread (Metastasized) to other organs of the body Letters or numbers after the T, N, and M give more details about each of these factors. To make this information somewhat clearer, the TNM descriptions can be grouped together into a simpler set of stages, labeled with Roman numerals. In general, the lower the number, the less the cancer has spread. A higher number means a more serious cancer.

resection

surgery to remove part or all of an organ or other structure.

prognosis

(prog-no-sis) a prediction of the course of disease; the outlook for the cure of the patient. For example, women with breast cancer that was detected early and who received prompt treatment have a good prognosis.

monoclonal antibodies

antibodies made in the laboratory and designed to target specific substances called antigens. Monoclonal antibodies which have been attached to chemotherapy drugs or radioactive substances are being studied to see if they can seek out antigens unique to cancer cells and deliver these treatments directly to the cancer, thus killing the cancer cells without harming healthy tissue. Monoclonal antibodies are also used in other ways, for example, to help find and classify cancer cells.

mediastinoscopy

(me-dee-as-tin-OS-ko-pee) examination of the chest cavity using a lighted tube replaced under the chest bone (sternum). This allows the doctor to see the lymph nodes in this area and remove samples to check for cancer.

margin

edge of the tissue removed during surgery. A negative margin is a sign that no cancer was left behind. A positive margin indicates that cancer cells are found at the outer edge of tissue removed during surgery. It is usually a sign that some cancer remains in the body.

lymph nodes

small bean-shaped collections of immune system tissue such as lymphocytes, found along lymphatic vessels. They remove cell waste and fluids from lymph and help fight infections. Also called lymph glands.

lymph

(limf) clear fluid that flows through the lymphatic vessels and contains cells known as lymphocytes. These cells are important in fighting infections and may also have a role in fighting cancer.

mesothelioma

a tumor derived from mesothelial tissue, such as the peritoneum (lining the abdomen) or pleura (lining the lungs). More on mesothelioma.

extrapleural pneumonectomy

(EPP) surgery to remove the pleura, diaphragm, pericardium, and entire lung involved with the tumor. You can view a web cast from Brigham and Women's Hospital in Boston of this procedure being done by Dr. David Sugarbaker: see the extrapleural pneumonectomy (EPP) web cast here.

Okuda K, Sasaki H, Kawano O, Yukiue H, Yokoyama T, Yano M, Fujii Y.

Department of Oncology, Immunology and Surgery, Nagoya City University Graduate School of Medical Science, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan.

Abstract

Epidermal growth factor receptor (EGFR) is overexpressed in a variety of epithelial malignancies. In lung cancer cases, EGFR gene mutation at the kinase domain and EGFR gene amplification are reported to be predictors of the response to EGFR tyrosine kinase inhibitors. In malignant pleural mesothelioma (MPM), the role of EGFR is less clear. We studied EGFR gene mutation, amplification and protein expression in 25 Japanese patients with MPM. None had previously reported EGFR mutations detected by the TaqMan PCR assay. Using immunohistochemistry, 8/25 (32%) cases were positive for the EGFR protein. The cases of sarcomatous type and desmoplastic type were all negative. Fluorescence in situ hybridization analysis revealed three low polysomy cases and one high polysomy case. The low polysomy cases included one biphasic type and two epithelial
types, and the high polysomy case was epithelial type. These four cases expressed EGFR protein. In MPM, EGFR seems to play a role in a limited subset of patients. To identify possible candidates for EGFR tyrosine kinase in inhibitor therapy, the information on the EGFR gene status may be valuable.

Keywords: Malignant pleural mesothelioma, Epidermal growth factor receptor, Amplification, FISH, Immunohistochemistry

Glossary

therapy

any of the measures taken to treat a disease. Unproven therapy is any therapy that has not been scientifically tested and approved. Use of an unproven therapy instead of standard (proven) therapy is called alternative therapy. Some alternative therapies have dangerous or even life-threatening side effects. For others, the main danger is that a patient may lose the opportunity to benefit from standard therapy. Complementary therapy, on the other hand, refers to therapies used in addition to standard therapy. Some complementary therapies may help relieve certain symptoms of cancer, relieve side effects of standard cancer therapy, or improve a patient's sense of well-being. The ACS recommends that patients considering use of any alternative or complementary therapy discuss this with their health care team.

oncology

(on-call-o-jee) the branch of medicine concerned with the diagnosis and treatment of cancer.

mutation

a change; a change in a gene.

in situ

in place; localized and confined to one area. A very early stage of cancer.

immunology

(im-mune-ahl-o-jee) study of how the body resists infection and certain other diseases. Knowledge gained in this field is important to those cancer treatments based on the principles of immunology.

gene

a segment of DNA that contains information on hereditary characteristics such as hair color, eye color, and height, as well as susceptibility to certain diseases. Women who have BRCA1 or BRCA2 gene mutations (defects) have an inherited tendency to develop breast cancer.

cancer

malignancy; a group of diseases typified by abnormal, generally out-of-control, cell growth.

mesothelioma

a tumor derived from mesothelial tissue, such as the peritoneum (lining the abdomen) or pleura (lining the lungs). More on mesothelioma.

epidermal growth factor receptor

The process of cell division, growth, differentiation and death is a highly regulated process. Several class of trans membrane receptors play a pivot role in this process, of these, epidermal growth factor receptor (EGFR) a member of Receptor Tyrosine Kinase (RTK) family are best known. These comprises of four receptors Erb B1/HER 1, Erb B2 / HER 2, Erb B3/ HER 3, and Erb B4 / HER 4. Of these HER 2 is the most favoured target. (Source: Manoj Pandey and K Chandramohan)