lung neoplasias Flashcards
Benign and borderline neoplasms uncommon in lung
Pulmonary hamartoma (benign)
Diffuse pulmonary lymphangioleiomyomatosis (borderline)
Inflammatory myofibroblastic tumor (borderline)
Metastatic neoplasms are very common
in lung
First capillary bed found by tumor cells circulating in systemic venous blood
Epithelial lung malignancies
Most common cause of cancer death, USA & world
Most who develop lung cancer-DIE FROM IT
1 year survival is 44% (5 year survival 17%)
Vast majority are epithelial neoplasms, i.e. carcinomas (90-95%)
Carcinoids are 5% of primary lung tumors
Pulmonary Hamartoma - characterized by
popcorn calcifications
Diffuse Pulmonary Lymphangioleiomyomatosis (LAM)
neoplastic perivascular epithelioid cells (PEC)
Leads to cystic emphysematous lung appearance
Dyspnea +/- recurrent spontaneous pneumothoraces
Usually in young woman
Tumor cells have estrogen and progesterone receptors
tuberous sclerosis associated
RX – Estrogen withdrawal (blockers, androgens, oophorectomy)
mTOR inhibitors being evaluated
Lung transplantation is the only definitive treatment, but can recur post transplant
Inflammatory Myofibroblastic Tumor
Rarely metastasizing proliferation of spindle-shaped myofibroblasts
Occurs throughout the body, including lungs
15 congenital cases described (endobronchial location)
Lung Cancer Epidemiology
Second most common cancer in both genders in the USA*
Leading cause of cancer deaths in both genders
Summary of adverse effects of smoking
Chronic bronchitis, emphysema
Myocardial infarction
Systemic atherosclerosis
(peptic ulcer)
Lung cancer (11% of heavy users) Oral cancer Pharyngeal cancer Laryngeal cancer Esophageal cancer Pancreatic cancer Cervical cancer Renal cancer Bladder cancer
carcinogenic cigarette components
polycyclic aromatic hydrocarbons- carcinogenesis (targets lung, larynx)
phenol– tumor promotion
nitrosamine– carcinogenesis
4-aminobiphenyl, 2-naphthylamine (–> blader cancer)
Environmental lung cancer risk factors
Radiation (uranium miners, atomic bombs, nuclear plant disasters)
Asbestos (20% of asbestos related deaths; mesothelioma)
Radon in uranium miners (radioactive gas)
Polycyclic hydrocarbons (burning fossil fuels)
Silica, bis-ether, nickel, arsenic, chromium, mustard gas
Molecular Genetics
- mutations in lung cancer
EGFR and KRAS mutations appear to be mutually exclusive*
Can successfully use EGFR inhibitors in EGFR+ adenocarcinomas
Squamous CC: del3p, CDKN2A/ p16, TP53, RB, EGFR
AdenoCA: TP53, EGFR, KRAS
Small CC: TP53, RB, del3p
Lung CancerSigns and Symptoms
Pain, hemoptysis, weight loss, underlying chronic lung disease symptoms
Local direct effects related to endobronchial growth
atelectasis, bronchiectasis & infections (abscesses)
Direct extension into mediastinum/chest wall and other structures
- superior vena caval syndrome
- pericarditis and pleuritis
Metastatic disease symptoms
- nodes involved in 50%
Paraneoplastic/endocrine syndromes
hoarseness can suggest
involvement of the recurrent laryngeal nerve (lung cancer squishing it?)
Pancoast tumor
apical lung tumor with pain in distribution of ulnar nerve and Horner syndrome (enophthalmos, ptosis, miosis, and anhidrosis)
Paraneoplastic Syndromes
ADH (hyponatremia)
ACTH (Cushing syndrome)
PTHrp (hypercalcemia) ** Remember - seen more with squamous cell carcinoma! ** [think this when no sign of boney metastases]
Calcitonin (hypocalcemia)
Gonadotropins (gynecomastia, etc.)
Serotonin, VIP, bradykynins, etc. (carcinoid syndrome with diarrhea and flushing)
Lambert-Eaton myasthenic syndrome (Abs to neuronal Ca++ channel)
Peripheral neuropathy
Dermopathies (acanthosis nigricans)
Hypertrophic pulmonary osteoarthropathy
Hematologic abnormalities (leukemoid reaction)
Hypercoagulable state (Trousseau syndrome)
Guidelines for Lung Cancer Screening
Annual LDCT (low dose CT scan) be offered
smokers or former smokers between 55 and 74 years old
have smoked for at least 30 pack-years
A drawback of LDCT is the overdiagnosis of benign nodules.
Average nodule detection rate with LDCT is 20%
> 90% of nodules found in this screening are benign
Squamous cell carcinoma histology
look for pink keratinization of the cytoplasm, intercellular bridges (desmosomes between the squamous cells)
adenocarcinoma– tumor forms glands
small cell carcnioma- smaller cells, very little cytoplasm, pushed against each other (nuclear molding), salt and pepper nuclei
Large cell– no glands, no intercellular bridges, no nuclear molding
Squamous Cell Carcinoma
Central, endobronchial growth, some peripheral Precursor lesions (Metaplasia, Dysplasia, CIS)
May have hypercalcemic paraneoplastic syndrome
(parathyroid hormone-related protein - PTHrp)
squamous cell carcinoma cytology
papa nicholau stain
orange color- karatinization
strap cells-
squamous pearl- layers of squamous cells maturing
Adenocarcinoma
Most common cancer in women and nonsmokers
Tend to be more peripheral
Precursor lesion: atypical adenomatous hyperplasia
Mucin production common
TTF1 positive (thyroid transcription factor)
may be related to scarring: Scar Carcinoma
Adenocarcinoma Histologic Grading
Well differentiated (Low Grade) Moderately differentiated (Intermediate Grade) Poorly differentiated (High Grade)
Mucinous adenocarcinoma- tons of mucin production with malignant tissues floating in it.
Adenocarcinoma cytology
“zellballen” with vacuoles
can look like a signet ring
Adenocarcinoma in Situand Microinvasive Carcinoma
may be unifocal, multifocal, lobar or diffuse (pneumonia-like consolidation that can cause asphyxia)
Adenocarcinoma in situ (bronchioloalveolar carcinoma)
- less than 3 cm with growth along alveolar septa, no invasion by who definition
Microinvasive (minimally invasive) carcinoma
- less than 3 cm with same appearance but with less than 5 mm of invasive component
May spread aerogenously
Large Cell Carcinoma
Central or peripheral
Small percentage actually large cell neuroendocrine
