notes by dr Claudio Italiano
The histological classification used is that of the WHO; however, the most important distinction is between a small cell carcinoma (SCLC) and a non-small cell carcinoma (NSCLC).
The staging of lung tumors is a modality through which we try to sort, according
to the extension, the different lung tumors and consequently to standardize the
different chemo / radio / surgical treatments.
Over the years numerous classifications have been proposed for bronchogenic
carcinomas, the one currently used is the one proposed by the World Health
Organization (WHO).
It represents the histotype characterized by small-sized cells, which very
often accompanies diffuse metastases. It differs from the NSCLC in that it is
characterized, above all in the line, by a good response to chemotherapy (with a
high total / partial regression of the disease) due to the high proliferative
activity of the cells that form it.
From a stadiative point of view it is distinguished in:
Limited disease (LD): localized to the lung and therefore irradable.
Extended Disease (ED): with the presence of distant metastases.
NSCLC (not small cell lung cancer or non-small cell lung cancer):
The NSCLC includes at least 4 histotypes:
- Squamous carcinoma
- adenocarcinoma
- anaplastic with large cells
It is the most frequent. It is the most frequently recognized form of etiopathogenesis in smoking. It is localized in the main and lobar bronchi, is grayish-white in color and grows inside the lumen, with an exophytic growth, with plaques on the bronchial surface, with a proliferating endoluminal endophrodial mass, ie around the wall of the lumen or with infiltration of the surrounding parenchyma, with cough and hemorrhagic sputum that allows diagnosis in a short time, but sometimes it is subtle and treacherous, grows slowly and gives only late signs, not being able to recognize it even to the CT scan.
Adenocarcinoma: usually occurs as a peripheral lesion. In recent years its incidence has significantly increased, representing the most common histotype not only in women. It is distinguished in adenocarcinoma of bronchial derivation (the most frequent form) and BAC (bronchioloalveolar carcinoma, which originates from the epithelium (ie coating surface) of the alveoli (site of the air-blood exchange) Acinar, papillary, bronchioclonal forms , adenocarcinoma with mucin formation, mixed forms with other variants.This is a neoplasia more frequent in women and in non-smokers (although cigarette smoking is a risk factor for this tumor too) .These are peripheral tumors, mantellaries, often with fibrous scars, microscopically there are tubules or papillae, with intracitoplasmatic mucin and positive PAS material in the cytoplasm The alveolar bronchial adenocarcinoma is not related to sex, smoking or occupation and is also a tumor of the periphery of the lung, highly differentiated , which grows along the alveolar septa, simulating lobar pneumonia, we distinguish the mucinous type, with colonnial cells ari, mucus secreting and non-mucinous, round-cubic cells, with a bullet arrangement (type II pneumocitis or Clara cells).
It is poorly differentiated: it has a worse performance than the two previous histotypes because it is more aggressive. It exists in clear cells and other variants, ie it is a non-small cell carcinoma, in which a differentiation in squamous or adenocarcinoma is not recognized, therefore in the glandular sense. It is a very aggressive tumor compared to ca. squamous and adenoca, which does not respond to treatment and relapsed easily. Fortunately rare. These are large neoplastic cells with abundant cytoplasm and irregular nuclei, with many nuclei and extensive areas of necrosis.Staging
For NSCLC the classification is based on the TNM, where for T, N, M we mean:
1) T evaluates the size of the tumor and its extension with respect to some
pleuro-pulmonary structures.
2) N evaluates lymph node involvement, that is, the presence of malignant cells
in the lymph nodes.
3) M indicates the presence of metastases (i.e. solid organs in which there is
evidence of lung-derived cells). THE
most frequent sites of lung cancer metastases are: brain, adrenal glands (small
glands located over the
kidneys), liver, bones.
For "T" there are four levels:
T1: tumor equal to or less than 3 cm without involvement of the visceral pleura
and / or the main bronchus.
T2: tumor larger than 3 cm or any size but located 2 cm from the
carena tracheal, or involving the visceral pleura, or causing pulmonary
atelectasis.
T3: any size as long as it infiltrates the thoracic wall, the diaphragm, the
medistinal pleura, of atelectasis of a
whole lung or is within 2 cm of the tracheal carena.
T4: any tumor invading the mediastinum, heart or great vessels, trachea or
vertebral body, the keel, which
have multiple nodules in the same lobe and / or pleural effusion.
Four levels are recognized for "N":
N0: no evidence of lymph node metastases.
N1: metastases affecting the bronchial or hilar lymph nodes ipsilateral to the
primary tumor.
N2: metastases affecting the ipsilateral mediastinal and carinal lymph nodes.
N3: metastases affecting the hilar, mediastinal and contralateral or
supraclavicular lymph nodes.
For "M" there are two levels:
M0: no evidence of distant metastases.
M1: presence of distant metastases. **
Neoplasms with nodules in ipsilateral lung lobes other than the one in which it
is also considered M1 are also considered
localized the tumor, as well as the presence of laterocervical lymph nodes.
The combination of the different T, N and M determines the staging.
Those listed below correspond to the subdivision into the 4 main stages with
their respective subtypes.
Stage Ia: T1N0M0
Stage Ib: T2N0M0
Stage IIa: T1N1M0
Stage IIb: T2N1M0; T3N0M0
Stage IIIa: T1N2M0; T2N2M0; T3N1M0
Stage IIIb: any T N3M0; T3N2M0; T4 any N M0.
Stage IV: any T, any N, M1.
(also combined forms), a very complicated tumor to be documented with
diagnostics, also associated with cigarette smoke, very dangerous and aggressive
due to the frequent metastases it gives. It can give systemic problems such as
skin rash, hormones, fever and serotina better responds to chemotherapy rather
than radiotherapy or surgery. It occurs in small cells, similar to lymphocytes
even if they are 3-5 times larger, differentiated with immunohistochemistry;
there are three subtypes:
1) "Oat cell" or small oatmeal cells (elongated conformation of the nuclei);
2) Intermediate, more voluminous cells
3) Mixed between these first two (a and b) or still associated with squamous
carcinoma
• Carcinoma with sarcomatoid elements
Carcinoid
• Unclassified carcinomas
The symptoms can vary depending on whether the tumor affects the central parts and large bronchi, having bronco-occlusion, ulceration of the bronchus wall and central necrosis. Other times the patient presents a severe bronchostenosis (see auscultation of the thorax) and listen to the hissing dry noises, while the subject stretches the respiratory muscles and engages them all and gasps, has always breathlessness and hunger for air and calls for an increase in speed of mask oxygen. Bronchostenosis is a cause of atelectasis and bronchial ectasia, but also of suppurative facts, of pneumonia and abscesses. If the bronchus is ulcerated, it will appear hemoptysis, that is spit of blood, which is emitted with coughing: this is a very dangerous signal! Other times it is the peripheral metastases to give the most important signals, such as Pancoast's syndrome, ie the infiltration of the brachial plexus and the sympathetic chain, with palpebral ptosis, dysphonia, with pain in the arm and shoulder. Basically the symptoms are related to the spread of the neoplasm, if the main bronchus is affected, then there will be recurrent bronchopneumon processes, with expectoration and cough; if the mediastinum is affected, the symptoms are those of a mediastinal invasion, with involvement of the laryngeal nerve or recurrent and dysphonia. If the phrenic nerve is affected, the diaphragm will be paralyzed, if the pleura is invaded, a pleurisy picture can be obtained with an imposing pleural effusion. There may also be signs of liver metastasis spread, usually with signs of liver failure, or cholestasis, ie with obstructive jaundice in the terminal phases and with transaminase uprising, gamma GT and alkaline and bilirubin phosphatase. If the ilari lymph nodes are taken, then atelectasis will occur, ie the lung will collapse, as the passage of air into the alveoli is not possible.
>> Therapy for lung cancer