Intro to Clinical Oncology Flashcards
Most common malignancies and most common causes of death
Most common malignancies:
- Prostate/breast
- Lung/Bronchus
- Colon
Most common causes of death
- Lung/bronchus
- Prostate/breast
- Colon
How does cancer present?
- Local symptoms of disease:
- Interference with normal organ function –> bowel obstruction, cough
- Direct extension into adjacent organ/structures –> chest wall pain - Symptoms of metastatic disease:
- Pain or organ dysfunction from disease that has pread to other organs –> bone pain, seizures, headache - Paraneoplast:
- Abnormal hormone production - Incidental or screening
Presentations of hematologic malignancies
- Bone marrow failure
- anemia –> weakness, fatigue, dyspnea
- thrombocytopenia –> bleeding, bruising
- leucopenia –> infection - Bone marrow proliferation
- erythrocytosis (PCRV) –> headache, plethora
- thrombocytosis –> thrombosis, bleeding
- leukocytosis –> dyspnea, confusion
- splenomegaly - Lymphadenopathy
- B-symptoms: fever, night sweats, weight loss
- due to elaboration of cytokines - Thrombosis
Signs (physical findings) and symptoms (what the patient reports)
Local symptoms:
- pain
- mass
- organ dysfunction –> symptoms depend on the organ
- direct extension to adjacent organs –> e.g. difficulty swallowing due to a tumor in the bronchus obstructing the esophagus
Metastatic disease:
- lumps, bumps
- pain
- symptoms referable to disruption of normal organ function –> obstruction, seizure, paralysis, fracture
Paraneoplastic symptoms
Symptoms that result from various substances secreted by the tumor or as a response to the tumor –> not a direct effect of malignancy
- weight loss without GI tract obstruction
- hypercalcemia
- hyponatremia
- “clubbing”
DVT and pulmonary embolism = common presentation and/or complication due to hypercoagulability
- requires immediate diagnosis and anticoagulation
- potentially fatal
Clubbing
Cutaneous signs of malignancy –> can be direct extension, paraneoplastic or metastatic
- cutaneous metastases generally associated with poor prognosis
Cancer anorexia and cachexia –> weight loss is common (>10%)
- frequent presenting sign
- usually associated with advanced disease
- etiology is controversial
Difference between incidental finding and screening
Incidental = patient evaluated for another reason
- frequently, an unsuspected radiologic finding
- major source of medicolegal problems
Screening
- recommended for breast, colon, cervical, lung in certain patients (sprial CT)
- prostate (PSA blood test) is controversial
- more complex than most appreciate
Screening for cancer
Detecting cancer before symptoms and signs
- basic premise is that smaller/earlier is better –> proven to be true in some disease, but not in others
- level of benefit varies –> best where the site of tumor is directly sampled (e.g. pap smear or colonoscopy); less effective when radiologic imaging is used (e.g. mammography or CT scan)
Current recommended screening for standard risk population
- Breast cancer –> mammography after age 50
- Colon cancer –> colonoscopy after age 50
- Cervical cancer –> pap smears
- Head and neck cancer –> evaluation during dental exam
- Prostate cancer –> PSA testing in males >50 (controversial)
- Lung cancer (as of 2011) –> low dose helical CT for patients with significant smoking history, >55, only at institutions with substantial expertise
Diagnosis of cancer
There must be histologic or cytologic proof of disease –> rare exceptions
- biopsy should be from the most accessible, least dangerous place –> generally, if you prove a cancer from a distant site, you do not need to biopsy the primary tumor unless curable approaches to both sites would be changed
- the biopsy should come before the rest of the evaluation, however a certain degree of radiographic evaluation is frequently performed simultaneously
Example of biopsy dilemmas:
1 41 y.o female presents with a breast lump and a single bony swelling in the distal femur. Biopsy of breast = infiltrating ductal cancer
- should the leg also be biopsied? –> YES! if low grade chondrosarcoma, patient could have two ultimately curable neoplasms
2. 50 y.o. male smoker presents with pancytopenia and a lung mass apparent on chest x ray. Bone marrow biopsy = diagnostic of small cell lung cancer
- can proceed with tx for small cell lung cancer
The diagnostic biopsy
- need a diagnosis –> “suspicious” and “possible” are not good enough, need the definitive proof for diagnosis
- need enough tissue to perform special stains and other analysis –> FNA usually not enough
- immunohistochemistry –> can distinguish tissue of origin in difficult cases
- molecular analysis –> for therapeutic decisions (Her2/neu, EGFR, k-ras, etc.)
Staging
- clinical vs. pathological staging
How extensive is the cancer?
- TMN system
- other factors –> tumor markers
- therapy is stage directed but not mandated
- staging systems do not incorporate all known variables –> therefore, therapy is determined by stage in addition to other factors (physiology, patient preferences, local expertise)
- staging does not incorporate performance status
Clinical vs. pathological staging
- clinical stage = stage determined after complete clinical assessment (physical exam, laboratory, radiologic, biopsy, mediastinoscopy, etc.) –> clinical stage frequently underestimates the extent of disease
- pathological stage = stage determined after resection (or attempted resection) OR pathological determination of metastatic disease
Tumor board
Organized meeting of internal medicine, surgical, and radiation oncologists –> include radiologists and pathologists
- review all evidence and assign clinical and/or pathologic stage
- recommend treatment approaches
- OK to use staging manuals –> guidelines change frequently
- important to have in mid the clear staging criteria for curative intent in each tumor type
Performance status
Considers the general ability of a patient to do things –> 2 major scales
- Karnofsky –> percentage score, more detailed
- Eastern Cooperative Oncology Group
- -> 0 = no limitations
- -> 1 = OOB all day, capable of a full day of work
- -> 2 = OOB > 50% of the day, limited ability to work
- -> 3 = OOB < 50% of day –> capable of self care
- -> 4 = requires nursing assistance with ADL
- ->5 = dead
How is staging accomplished?
- History and physical
- Radiographic studies
- Laboratory evaluation
- Invasive and surgical
- Clinical vs. surgical staging
Radiographic studies in cancer diagnosis
- Plain films = chest X ray –> easy, inexpensive, useful for initial assessment and follow up
- CT = best method for many disease –> excellent imaging of most organs
- need IV contrast (iodinated) for best assessment usually
- easy and relatively inexpensive - MRI = best method for imaging the brain and spinal cord
- useful in certain special situation in chest and liver
- cannot use in patients with ferrous metals in the body
- slightly more difficult to obtain and more expensive than CT - PET scans = assessment of undiagnosed masses to determine malignant potential
- useful as part of staging evaluation for lung and other cancers
- requires 18FluoroDeoxyGlucose isotope
- expensive, limited availability
- may ultimately prove valuable in follow up
- currently overutilized –> PET avidity and value in each cancer has yet to be established - PET/CT
- Ultrasound
