Primary treatment is the first-line therapy, and in certain tumor types may be
referred to as induction therapy. Choice of primary treatment is governed by
observations made from clinical trials that demonstrate that a given regimen has the
highest known activity against the tumor. These regimens may include chemotherapy,
targeted agents, endocrine agents, or biologic response modifiers. Second-line
treatment is administered after the tumor has become refractory to primary therapy or
if the patient is unable to tolerate first-line therapy. Systemic therapy is frequently
used in different ways during the course of an individual’s malignancy. Primary
treatment can be either curative or palliative, depending on the specific type of tumor
48 After primary therapy, patients may receive additional treatment in an
attempt to further eradicate residual disease and improve their chances for long-term
survival. This treatment may be termed consolidation, intensification, or maintenance
therapy. See subsequent chapters for specific discussion of the use of primary,
consolidation, or maintenance therapy in the treatment of hematologic and solid tumor
QUESTION 1: F.R., a 58-year-old woman with no other medical problems, recently underwent surgical
recommended now when she has no detectable disease?
Micrometastases or residual disease may still be present in some patients after
primary treatment. These patients have a high probability of disease recurrence, even
though the primary treatment may have successfully removed all visual evidence of
the primary tumor. To eradicate any undetectable tumor in these patients, systemic
therapy after initial curative surgery (or radiation therapy) may be recommended.
Systemic treatment administered after primary therapy (in the case of F.R., primary
therapy was surgery) is referred to as adjuvant therapy. Because the tumor burden is
relatively low at this time, adjuvant therapy should immediately follow primary
therapy. For adjuvant therapy to provide benefit, the risk of tumor recurrence must be
high, and effective agents must be available to eradicate the tumor. Adjuvant therapy
is considered standard of care for some stages of breast, lung, and colorectal cancer,
but it also has benefited selected patients with ovarian cancer, Ewing sarcoma,
Wilms tumor, and other malignancies (Table 93-7).
48 The duration of administration
of adjuvant therapy varies depending on the type of cancer being treated and the
drugs being used, but is typically several weeks to months in duration. See
subsequent chapters for specific discussion of the use of adjuvant therapy in solid
tumor malignancies. F.R. will receive adjuvant chemotherapy with six to eight cycles
of carboplatin and paclitaxel.
Neoplasms for Which Adjuvant Systemic Therapy is Indicated After Primary
Lippincott Williams & Wilkins; 2008:339, with permission.
Because it is difficult to detect micrometastases or residual disease, it is a
challenge to determine which patients should receive adjuvant therapy. To help with
these decisions, clinicians frequently consider histologic and cytogenetic
characteristics of the primary tumor that are associated with high risk of relapse.
Neoadjuvant therapy is given before the primary treatment (typically surgery or
radiation) in patients who present with locally advanced tumors (e.g., large tumors or
those that are impinging on surrounding vital structures) that are unlikely to be cured
with primary therapy alone. The objective of neoadjuvant therapy is to reduce the
tumor mass, thereby increasing the likelihood of eradication by subsequent surgery or
radiation. Neoadjuvant therapy also can lessen the amount of radical surgery the
patient needs, which can preserve cosmetic appearance and function of the
surrounding normal tissues. The tumor can be resistant to neoadjuvant therapy and
continue to grow, however, making surgery or radiation even more difficult. Patients
may also experience toxicities with neoadjuvant therapy that may delay surgery or
impair postsurgical healing. Locally advanced tumors in which neoadjuvant therapy
has been shown to improve survival rates include non-small-cell lung cancer, breast
cancer, sarcomas, esophageal cancers, laryngeal cancer, bladder cancer, and
osteogenic sarcoma (Table 93-8).
48 See subsequent chapters for specific discussion
of the use of neoadjuvant therapy in solid tumors.
QUESTION 1: H.P. is a 57-year-old man who is currently undergoing a staging workup for a presumed
By understanding the mechanisms by which cancer cells exhibit unregulated growth
and immortality and possess the ability to invade tissues and metastasize, it has been
possible to design drugs that inhibit these processes.
Directed at specific receptors associated with cancer, monoclonal antibodies block
ligands from binding to their targets. Unlike traditional chemotherapy, monoclonal
antibodies selectively target receptors or their ligands known to potentiate cancer
pathways, and as a result, minimize toxicity to noncancer cells. Table 93-9 provides
a list of monoclonal antibodies currently approved by the US Food and Drug
Administration to treat malignancy.
Tyrosine kinase inhibitors (TKIs) are small molecules that directly inhibit tyrosine
kinase activation by competing with ATP for binding to the intracellular tyrosine
kinase domain. Advantages of these inhibitors include inhibiting cells that may not
overexpress the receptor on their surface or have mutated forms of the receptor that
result in its activation and direct inhibition of cell signaling. Even though most TKIs
are designed to inhibit a single target, they often have inhibitory properties for
additional molecules, which could affect an internal cascade of biologic activity
resulting in antitumor activity and toxicity.
Neoplasms for Which Neoadjuvant Systemic Therapy is Indicated for Locally
Philadelphia, PA: Lippincott Williams & Wilkins; 2008:338.
This class of drug is taken orally. Due to varying pharmacokinetics, specific
instructions on self-administration should be provided to patients (i.e., take on an
empty stomach, take with a full meal). Additionally, many TKIs are substrates,
inhibitors, and inducers of CYP P450 enzymes. Attention to potential drug interaction
is crucial to safe medication use.
Table 93-10 provides the TKIs currently approved by the US Food and Drug
Administration to treat malignancies.
Because more information is learned regarding signal transduction pathways and
cellular growth and proliferation, more drugs are being developed that target these
key molecules. Histone deacetylase (HDAC) inhibitors, mammalian target of
rapamycin (mTOR) inhibitors, and proteasome inhibitors are examples of drugs that
have novel mechanism(s) of action. Table 93-11 lists these and other targeted agents
currently approved by the US Food and Drug Administration to treat malignancies.
Combination Therapy with Targeted Agents
The optimal activity of adding targeted agents to cytotoxic chemotherapy is difficult
to predict. Knowledge about how to combine targeted agents with chemotherapy is
limited, although clinical investigations are ongoing. See subsequent chapters for
specific discussion of the use of targeted therapy with chemotherapy in solid tumor
Endocrine therapy can be used to treat several common cancers, including breast,
prostate, and endometrial cancers, which arise from hormone-sensitive tissues
(Table 93-12). These tumors grow in response to endogenous hormones that trigger
growth signals. Current endocrine therapies inhibit tumor growth by blocking
hormone receptors or by eliminating endogenous hormone feeding the tumor. Not all
tumors arising from hormone-sensitive tissues respond to endocrine manipulation.
Lack of response may be associated with hormone-resistant tumor cells or inadequate
suppression of the endogenous feeding hormones.
Immune therapy is comprised of substances that stimulate the body’s immune system
to identify circulating tumor cells. Some agents target certain cells of the immune
system; other agents are more nonspecific.
34 An individual’s immune system plays a
crucial role in developing or eradicating cancer. Normally, an intact immune system
can protect the host against malignant cells and infectious pathogens, but current
evidence shows that individuals with “weakened” immune systems are at an
increased risk of developing cancer. Immunotherapy can include vaccines, cytokines,
a Agent (Trade Name) Mechanism of Action Notable Toxicities
Blinatumomab (Blincyto) Binds to CD19 on B cells and
formation of cytolytic synapses
Neurotoxicity; infection; tremor;
diarrhea, constipation; cytokine
Anti-CD20 Obinutuzumab (Gazyva) Binds to CD20 on B cells;
renal dysfunction; electrolyte
abnormalities; infection; infusion
Ofatumumab (Arzerra) Binds to CD20 on B cells at
rituximab; induces cell death via
Rituximab (Rituxan) Binds to CD20 on B cells;
cells and releases radiation (β
particles); induces cell damage
Infusion-related reaction; chills,
Tositumomab (Bexxar) Iodine-131 linked to rituximab;
releases radiation; induces cell
infection; hypothyroidism; see
notable toxicities for rituximab
which disrupts the microtubule
vomiting, diarrhea; fever; rash;
Anti-CD52 Alemtuzumab (Campath) Binds to CD52, leading to lysis
of CD52-positive leukemic cells
myelosuppression, opportunistic
infection, fever; nausea, rash
Anti-EGFR Cetuximab (Erbitux) Binds to EGFR, preventing
activation and inhibiting cell
Panitumumab (Vectibix) Binds to EGFR with higher
Papulopustular rash, pruritus;
of trastuzumab and microtubule
inducing cell cycle arrest and
constipation, diarrhea; fatigue,
Pertuzumab (Perjeta) Binds to HER2, inhibiting HER2
signaling, halting cell growth
Trastuzumab (Herceptin) Binds to HER2; induces cell
vomiting, diarrhea; infusionrelated reaction
Anti-VEGF Bevacizumab (Avastin) Binds to and inhibits VEGF
ligand interaction with receptors,
Ramucirumab (Cyramza) Binds to and inhibits VEGF2
ligand interaction with receptors
Ipilimumab (Yervoy) Enhances T-cell activation and
proliferation by inhibiting CTLA4; restoring antitumor immune
diarrhea, colitis; pruritus, rash;
Nivolumab (Opdivo) Enhances T-cell activation and
proliferation by inhibiting PD-1
constipation, diarrhea; fatigue;
arthralgia; cough, pneumonitis
Other Dinutuximab (Unituxin) Cell lysis of GD-2-expressing
hepatotoxicity; fever; capillary
leak syndrome; infusion-related
reaction; peripheral neuropathy
aAll monoclonal antibodies are administered intravenously, IV.
receptor; PD-1, programmed cell death-1; VEGF, vascular endothelial growth factor.
Sipuleucel-T (Provenge) is a cancer vaccine approved for patients with metastatic
prostate cancer that is resistant to prior endocrine therapy.
stimulated to recognize the patient’s own cancer cells. The cytokines, interferon-α
and interleukin 2, were the first immune-modulating therapies available. They
nonspecifically stimulate B- and T-cell proliferation and differentiation along with
activity on other immune functions.
Immune checkpoint inhibitors release the
brakes on the immune system, allowing it to identify and kill cancer cells better.
If H.P. is in fact diagnosed with stage IV adenocarcinoma of the lung, he may
receive other agents besides chemotherapy during the course of treatment for his
disease. For specific discussion of which noncytotoxic agents H.P may receive, refer
Name) Mechanism of Action Notable Toxicities
ALK inhibitor Inhibits ALK thereby reducing
tumor cell proliferation in cells
expressing ALK fusion protein;
Ceritinib (Zykadia) Also inhibits IGF-1R, insulin
Crizotinib (Xalkori) Also: dysgeusia; edema;
BCR-ABL inhibitor Inhibits BCR-ABL kinase, cKIT, and PDGFR kinases
Bosutinib (Bosulif) Includes activity against most
Also: electrolyte disturbances;
liver enzyme elevations; fever;
Dasatinib (Sprycel) Inhibits most imatinib-resistant
Also: headache; fluid retention,
Also: fluid retention; headache;
hepatic toxicity; musculoskeletal
Nilotinib (Tasigna) Inhibits most imatinib-resistant
hepatic toxicity; hyperglycemia;
Ponatinib (Iclusig) Inhibits most imatinib-resistant
arthralgias; constipation; hepatic
BTK inhibitor Irreversibly inhibits the BTK of
diarrhea; fatigue, edema, fever;
EGFR inhibitor Inhibits EGFR TK; resulting
Afatinib (Gilotrif) Irreversible inhibitor of EGFR as
Erlotinib (Tarceva) Reversible inhibitor of EGFR
HER2 inhibitor Reversibly inhibits HER2 and
Nausea, diarrhea; dermatologic
prolongation; pulmonary toxicity
MEK inhibitor Decreased cell proliferation and
increased apoptosis by inhibiting
PI3K inhibitor Inhibits PI3K expressed on B
diarrhea, colitis, gastrointestinal
VEGF inhibitor Inhibits VEGF receptor tyrosine Hypertension; diarrhea, nausea,
Axitinib (Inlyta) Also: electrolyte disturbances;
creatinine increased; fatigue;
Also inhibits FLT-3, KIT, MET,
stomatitis, weight loss, anorexia;
fatigue; electrolyte disturbances;
hand-foot syndrome, hair color
erythrodysesthesia; proteinuria;
Pazopanib (Votrient) Also inhibits c-KIT, PDGFR,
Also: depigmentation of hair and
Sorafenib (Nexavar) Also inhibits RAF kinases,
Sunitinib (Sutent) Also inhibits PDGFR-α and -
prolonged QT interval; palmarplantar erythrodysesthesia, skin
dysfunction; leukopenia; rash,
a All tyrosine kinase inhibitors are administered orally, PO.
fibroblast growth factor receptor; RAF, MAPK 3 kinase
Systemic chemotherapy is most commonly administered by the intravenous route,
either as a bolus injection (generally <15 minutes), short infusion (15 minutes to
several hours), or as a continuous infusion (lasting 24 hours to several weeks). Some
chemotherapy can also be administered orally, intramuscularly, or subcutaneously.
Targeted agents are most commonly administered intravenously or orally.
administered orally or subcutaneously.
Although chemotherapy was initially developed for systemic use, techniques have
been developed to administer agents directly to specific sites of the body affected by
the tumor (Table 93-13). Regionally or locally administered chemotherapy allows
for high concentrations of drug at the tumor site while reducing systemic exposure
and subsequent toxicity. However, a potential disadvantage is that distant
micrometastases may not be exposed to chemotherapy, allowing continued growth of
combination chemotherapy regimen. A recent CT scan of her abdomen showed marked shrinkage at several
tumor sites and her pain has decreased. How long should she continue to receive this chemotherapy?
An important step in the treatment process is assessing response to treatment. This
assessment should include evaluation of efficacy as well as toxicity, including impact
on the patient’s overall quality of life. Re-evaluation should occur at regularly
scheduled intervals and include physical examination, laboratory tests, and repeat
Response Evaluation Criteria in Solid Tumors (RECIST) was introduced in 2000
to unify response assessment criteria, define how to choose evaluable tumors, and
enable the use of new imaging technologies (spiral CT and MRI). The World Health
Organization, National Cancer Institute, and European Organization for Research and
Treatment of Cancer have adopted RECIST criteria as the standard for evaluating
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