What is cancer? Causes, stages and symptoms of cancer.
To begin an evaluation of a cancer we need more information on this condition :
- The causes of its occurrence
- The stage of the disease was
- Prognostic factors.
In order to understand the depth of all the details of the disease and all the related aspects that you have known every detail of the above. This information you get from your doctor specialist.
To obtain full medical name of the disease, its staging, and information related to the type of cells and ultimately prognostic factors will be conducted some tests. Copies of the results of all investigations that you will make will be stored for subsequent evaluation.
If you choose to document on condition that in the literature, it can be extremely useful both for finding general information and to discover the latest information strictly related to that form of cancer.
Treatment is tailored to each type cancers and is dependent on body condition at the start, cancer cell type, stage of disease.
Cancerous disease occurs due to uncontrolled division of certain cells with special characteristics, thus causing the appearance of a tumor mass. These cells that initiated uncontrolled division have called primary cells. Of primary cells forming tumor cells can detach from entering the circulation seeding other areas, giving rise to secondary tumors-metastases. Metastatic tumor cells in tumors retains primary cell type of origin.
For example, in malignant tumors of the colon can occur especially metastases in the liver. These metastatic liver tumors from primary tumors should be clearly differentiated liver situation where different therapeutic attitude. Also a tumor must be differentiated bone metastatic breast cancer in a primary bone tumor.
There are important differences that need to be made even between tumors that start in the same organ, differences in prognosis and treatment are important from one form to another. For this differentiation will be made explorations that will allow the establishment ‘s exact type of cancer in order to optimal therapeutic approach.
Diagnosis of cancer
The diagnosis of cancer is a laborious process that, although at first it may be clear evidence of a cancer will be determined after the items that will help shape that accurate diagnosis of cancer-the exact type and evolutionary stage.
The exact type of cancer and the histopathological diagnosis will be known precisely only after examining the biopsy tissue by pathologist. But there are certain forms of cancer in organs that can suspect from the beginning what it histopathological type. For example, in prostate cancer in the vast majority of cases we meet with forms of adenocarcinoma and cervical cancers also frequently meet carcinomas.
Staging
The state just like other prognostic factors will be specified after surgery and intraoperative assessment of tumor and satellite adenopathy. Postoperatively will be examined and evaluated by the pathologist entire tumor with lymph nodes excised. Therefore preoperative staging of tumor stage is only presumptive.
Despite these diagnostic uncertainties in the initial phase can begin, however depending on the diagnosis treatment that we have at this stage, followed by certification exact type of cancer shifted complex treatment of cancer based on specificity.
This division of cancers by stage is to classify patients by similar degrees of disease states and to offer a vision systematized treatment and prognosis. Thus, similar to patients with stage similar forms of cancer will have a similar prognosis and treatment. Therapeutic results may still differ from one patient to another depending on many factors such as general health, their beliefs and preferences related to treatment, different biochemical affinity for certain drug treatments.
This concept of staging cancers can be applied to all cancers except leukemia. In this form of cancer are localized cancer cells form a tumor but among cells circulating in the blood of the patient, tumor staging classic is impossible to create.
For staging of solid tumors, there are two systems :
- The classic that takes into account in particular the size of the tumor and divided tumors in stages I to IV
- TNM staging-more modern and complex.
Staging classic
- Stage I: generally includes small tumors without invasion and who in most cases are perfectly curable with favorable prognosis
- Stage II and III tumors include local invasion of surrounding tissue and lymph nodes, therapy and prognosis attitude is different depending on the time cells and the organ of origin ;
- Stage IV: in this stage are in general inoperable tumors, metastasis and prognosis reserved.
Unfortunately known cancers tend to relapse months or years after surgery with radical intent, which completely resected primary tumor. This is due to the persistence of cancer cells and the subsequent development of macroscopic tumor formation.
If the tumor occurs in the same area of the former primary tumors, talk about relapse, and if tumors occur away from the primary tumor is called metastasis. These cases of recurrence and / or metastasis are considered stage IV.
Staging of classes I to IV is replaced by the current TNM staging more detailed and precise.
TNM staging
If this is taken into account both staging both tumor size (T), lymph node invasion (N) and metastases (M). They are assessed separately and then classified by assigning numbers to the three elements sets stage disease.
For example T1N1M0 stage consists of a stage 1 tumor, invasion of the lymph nodes of degree 1, and no metastases. TNM staging is typical of all forms of cancer and may give a more accurate idea of the stage of disease.
T-tumor
Tumor classification is done with the numbers 0-4 :
T0-is the minimum tumor that has not yet begun to invade local structures, this stage is called the tumor “in situ”
T1, 2,3-represent intermediate stages between tumor “in situ” and invasion of adjacent organs, stages defined differently from one tumor type to another
T4-defines large tumor that invades all surrounding structures by direct extension and in most cases is inoperable.
Refers to lymph node invasion. It lies on the path lymphatic channels throughout the body and lymphatic stations role is filtering and synthesis of antibodies. When cancer cells detach from the tumor formation, they remain stuck in the lymph nodes, nodules increase in size and become hard consistency, their invasion was visible macroscopically. Other times their invasion is not visible but after evidarii macroscopic nodal surgery and sent to the histopathology can highlight their invasion. It is considered invasion of lymph nodes affected when regional nodes. When they invaded lymph nodes distant from the primary tumor it is ranked as metastasis.
N0-is the stage without lymphatic invasion
N1, 2,3-are intermediate stages which differ from one type of cancer to another
N4-is extensive invasion of the lymph along an axis of the lymphatic system.
M-metastasis
There are two stages for M : 0 and 1:
M0-when not reveal any metastasis, and
M1-when we highlighted peripheral metastases.
As seen system is more accurate than TNM staging system from I to IV, and more adaptable to each type of tumor. But correlations can be made between the two staging systems, for example staging TNM stage II represents T1-2N1M0-that we are dealing with a small tumor-average with minimal local invasion, with a small number of invaded lymph nodes without metastasis.
There are variations and changes of staging systems for certain forms of cancer because there is enough division in four stages. Thus appeared substages and IIa, IIIb and TNM system, T1b, T2a. The differences between these substages are defined for each type of cancer in part.
Even in stage M1-metastatic, the prognosis differs than one type of cancer to another, cancers originating in renal tissue may have a favorable prognosis in this stage as opposed to those that start in the colon. Differences are received and the location of metastases : liver, lung, bone, brain with different functional implications and different developments.
Both tumor staging systems are constantly improving and will likely suffer changes in order to adapt them. The goal is to be inferred with confidence prognosis and therapeutic attitude the best.
The differences are large from one type to another depending on cancer type and invasiveness of cells constituting the tumor TNM system lately adding another letter G-representing the degree of invasiveness of the cells revealed by microscopic pathologist : G1, 2,3,4. Depending on the grading and prognosis of cancer cells differ greatly.
Establishing the degree of invasiveness will be after departure from normal microscopic changes and the degree of cell division. High grades are generally aggressive cancers with local invasion and rapid development and nodular shortly high tendency to metastasize.
Tumor grade will be able to establish so only after microscopic examination by the pathologist when he has a tumor fragment or after surgery you will be out in full primary tumor and affected lymph nodes or a fragment derived from tissue biopsy performed and it in its turn Interventional puncture or biopsy.
Prognostic
Specific molecular test results may play an important role in prognosis and in dictating the type of treatment. An example of a specific biological implications in therapeutic attitude is the estrogen receptors in certain tumors according to the group into two classes: positive and negative estrogen. The positive cells contain estrogen receptors on their surface estrogen hormone treatments with favorable results.
There are other molecular tests which differ depending on the outcome of treatment and prognosis, the range of these explorations are extremely large and constantly diversifying.
Biopsy
For the diagnosis of the degree, type of cells and perform specific tests will therefore be to provide pathologist named biopsy tissue fragment, fragment will be obtained during surgery for removal of large primary tumor or local anesthesia through a small surgery performed solely to biopsy sampling, and other methods that will be discussed below. Pathologist specializing in the investigation of biopsy tissue fragments will produce a report after exploration that will make making available to the treating physician the information needed to start a specific type of treatment and prognosis.
There are several ways to collect biopsy material.
Types of biopsies
Excisional biopsy-is important in tumor fragment excision or entire formation in order to be examined. Currently this form of biopsy is largely replaced by new forms but there are certain types of tumors are more important data obtained with greater accuracy only after wide excision of malignant tissue.
Incisional biopsy-when only a small portion of tissue is taken for biopsy. This type of biopsy is common for superficial soft tissue tumors-tissue, fatty tissue, muscle and can establish whether we are dealing with a malignant or benign tumor.
Endoscopic biopsy-is the usual way of taking biopsy tumors of the gastrointestinal tract but urinary tract (cystoscopy), abdominal cavity (laparoscopy), inside joints (arthroscopy), tracheobronchial tree (bronchoscopy). Performed tract endoscope-a tube -shaped device equipped with light source, microcamera and pinching forceps. This system does not require removal of biopsy incisions and use body openings for the introduction of the endoscope. It will directly visualize the lesion and will tweak with special clamp a piece of tumor tissue biopsy enough. The fragment will be drawn out of the body and will be submitted for examination by the pathologist specialized service.
Colposcopy with biopsy-is a gynecologic procedure that has become usual and practice in order to evaluate patients with cervical changes. First is explored cervix and tissue fragments that will be taken for biopsy will be taken from the area where changes are most clearly visible.
Fine needle biopsy-is based on a very simple technique that is used as the syringe needle to be inserted into the tumor mass and aspiration will extract cancer cells to be placed on a microscope slide and will be offered pathologist for examination. The result of the expert can come in a few minutes.
Tumors in organs such as the pancreas, liver, lung or thyroid glands and, breast, can benefit from this type of biopsy and diagnosis can be subsequently targeted to intervene surgically. Fine needle biopsy can be practiced under radiological control, ultrasound or CT scan guidance to imaging. It may be general or local anesthesia depending on the situation and the patient’s tolerance.
Another type of biopsy used especially in dermatology is the removal of small skin slices using a special device. Injuries is minimal and will heal spontaneously or at least will be able to apply a suture practice.
Bone marrow biopsy-In case of abnormal cells in the circulating blood, an unexplained anemia, a number too large in circulating blood cell or platelet decline will require a marrow biopsy from which these cells-bone marrow-which is located inside of bones.
In adult bone marrow biopsy is taken usually posterior superior iliac crest of the pelvic girdle. They are on the back of the pelvis on both sides of the sacrum. It is a difficult maneuver and can be practiced by hematologist and even by your internist or family.
It can make a local anesthetic in the syringe needle to be inserted deeper to anesthesia and the membrane covering the bone-periosteum. After this we use a thick needle with sharp trocar mounted to a syringe. The needle will be inserted to the medullary space and aspiration will harvest bone quantity required. It looks like the blood but may contain small pieces of fat. This content taken from bone marrow expose on a glass slide and will be made available pathologist or hematologist for microscopic examination.
Preparing parts biopsy for examination
After the biopsy tissue is extracted from the body ill follow several procedures to obtain microscopic preparation itself in the form of blades. There are two techniques for obtaining histological sections with a thickness of 5 micrometers (0.0005 millimeters) to be displayed on glass slides for microscopic examination.
The first technique is the paraffin to obtain permanent preparations, you will have the quality to be examined in a long time. Fresh preparation will be introduced in a solution with a role that will be fixed in several hours time proportional to the size of the preparation. The solution is in most cases 10% formaldehyde that has the ability to preserve protein preparation and prevent their further distortion. This is probably the most important step in obtaining high quality dishes. Preparations so fixed in formaldehyde solution will be placed in specialized machines, where during the night will go through cycles of replacement water from their composition paraffin. The next morning the qualified personnel-Histology technicians-will take tissue preparations are in paraffin blocks and will make fine sections using a special device called a microtome. These sections will be performed in paraffin block and shall contain within them the section of biopsy material. These extremely thin sections will be taken with great care and will be displayed on glass slides for microscopic examination.
Such preparations will pass obtained by a coloring process. The most commonly used dyes for microscopic preparations hematoxylin (a natural product made from the wood of a shrub from Central America called Haematoxylon campechianum) and aniline-an artificial dye. Combinations are used dyes such as hematoxylin-eosin stained preparation which will in shades of pink and orange to blue. In this way you will more easily reveal distinct cellular elements. Typically cell nuclei are stained in dark blue and the cytoplasm and organelles have different coloration shades from pink to orange.
Frozen preparations-Extemporaneous-are created in order to be examined shortly after biopsy and they have quality as good as permanent preparations. Pathologist takes biopsy tissue from surgery, he freeze via a specialized and perform sections that will later be examined under the microscope slides and can thus provide results surgeon will tailor the surgical approach according to this result.
This is a quick process and very useful for the surgeon and patient bringing an important benefit, which will be able to make optimal surgery for their disease.
As frozen preparation can get information about the nature of tumor cells through fine needle puncture and exposure of cells on the blade. And in this case the blade is visualized in a short time under the microscope. Point can be guided ultrasound imaging or computer tomography (CT).
Examination piece
Macroscopic examination
Assessment of pathological play begins by examining his ticket macroscopic and supplemented the operating room. In most cases, tissue fragments are small and are sent along this note they are made some mentions about the song-why organ fragment originates from that area to which represent dimensions.
For example, a sigmoid polyp obtained using colonoscopy will be accompanied by air filled with the following data : polyp size, surface (smooth or rough Bösel), consistency (hard or soft), implantation (pedunculated or sessile) existence or mucosal infiltration colon in that area, color, friability, if bleeding or not expressing distance in centimeters from the anus and disposal colic wall (anterior or posterior). All this information is useful both for examining pathologist and surgeon’s part to adapt conditions of polyp surgery, where it will require.
When the pathologist sent whole organs or parts of organs as a result of resection, these will be accompanied by bulletins contain all the data descriptive of the song. For example if practiced splenectomy for Hodgkin’s disease (a cancer of lymph tissue) will complete the following information: spleen weight, dimensions (x / y / z cm), describing its surface, texture, color, whether or not defective the capsule are intact vessels in the hilum of the spleen, or whether we are dealing with thrombosis of its hilum, if we lymphadenopathy in the hilum and how many nodes are visible or affect their size.
Pathologist will perform sections of spleen and will perform microscopic preparations in those areas that are pathologically modified or who seem suspicious. By examining preparations will make accurate diagnosis of Hodgkin’s disease or other damage. Not all sections contain pathological changes but some of them accurate diagnosis is very important and also a great responsibility pathologist to it depending on the entire subsequent treatment. Along with the description of the type of damage detected by microscopic examination of the sections will be precisely and area of origin.
Microscopic examination
This consists of viewing under microscope slides prepared from various tissues and the formation of a full report pathologist all pathological elements.
An example of such a report would be the case polyp pathological sigmoid described above as follows: Section polyposis by a structure coated with a central axis of the lining of the vascular structure with the predominant adenomatous tube (which is available within the cell columns lining covering the polyp and that the sigmoid colon is cylindrical multilayered). In the cell nucleus is observed degree of hipercromatoza (representing an intense mitotic activity within nuclei marked tendency multiplication) with almost complete loss of cytoplasm (cell contents of the nucleus and cell membrane which are organelles). No stromal invasion is highlighted (no tendency to invade deeper layers-submucosa, muscle, serosa).
In the case described mucosal precancerous changes potentially malignant polyp but currently shows a favorable prognosis.
After examining macroscopic and microscopic subsequently will issue the final report-diagnosis. It will be the example given biopsy colonoscopy in the sigmoid colon adenomatous polyp representing.
In this form of expression concise diagnosis included many important data such as: the location of the lesion in the colon, called the sigmoid portion, biopsy sampling method by colonoscopy, which represents the structure sent-polyp and microscopic examination results and viewing changes that appear in the microstructure polyp-adenomatous.