COMMON MALIGNANCIES
| COLORECTAL CANCER—John H. Bond, MD, Professor of Medicine, University of Minnesota Medical School, and Department
of Medicine, Veterans Affairs (VA) Medical Center, Minneapolis
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| Introduction: colorectal cancer screening effective and should be done in appropriate population; debate continues on preferred
strategies
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| Prevalence: Americans have ≈6% lifetime risk of developing colorectal cancer (highest in world); colorectal cancer second
most common cause of cancer death; 5-yr survival (≈60%) has increased slightly since early 1990s (only in United
States); colorectal cancer only malignancy that affects men and women about equally; however, incidence of premalignant
polyps lower in women
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| Likelihood of survival: related to anatomic stage of cancer at time of surgery; if cancer localized in colon (stages 1 or 2 or
Dukes’ A or B) overall survival after surgery >85% (often close to 100%); if cancer has spread beyond bowel (stages 3
and 4; Dukes’ C and D) survival chances decreased by >50%; comment—by time symptoms develop in majority of patients,
cancer has already spread to lymph nodes
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| Objectives of colorectal cancer screening: detect surgically resectable cancers (stages 1 or 2 or Dukes’ A and B); prevent
cancers by detecting and resecting premalignant adenomatous polyps; remarks—95% of cancers arise in benign polyps;
≈10 yr required for cancer to develop; colonoscopic resection of adenomatous polyps reduces subsequent incidence of
colorectal cancer by ≥90%
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| Risk factors: age >50 yr most common risk factor; family history of colorectal cancer and/or adenomatous polyps (this cancer
most familial of all major malignancies; ≈20% to 30% of cases have genetic predisposition); personal history of colorectal
cancer or adenomatous polyps; long-standing inflammatory bowel disease (ulcerative colitis, Crohn’s disease)
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| Evidence-based screening guidelines: 1) primary care providers should interview patients about risk factors at fairly young
age (maybe in their 20s); 2) screening of average-risk patients should begin at 50 yr of age, but start earlier if special
risk present (eg, familial history of colorectal cancer or significant adenomatous polyp)
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 | Gastrointestinal (GI) Consortium (Agency for Health Care Policy and Research [5 GI societies]): established guidelines
in 1997 and revised them in 2003; recommended that several questions be asked of patients, starting in their late 20s or
early 30s; questions—1) are you asymptomatic? 2) history of colorectal cancer or removal of adenomatous polyps? 3)
history of inflammatory bowel disease? 4) first-degree relative(s) with colorectal cancer or significant adenomatous
polyp? 5) if so, at what age was it diagnosed? comment—younger relative diagnosed with cancer, the more likely patient
has familial risk
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| Composite screening options: 1) annual fecal occult blood test (FOBT); 2) flexible sigmoidoscopy (FS) every 5 yr; 3)
combination annual FOBT and flexible sigmoidoscopy every 5 yr; 4) double-contrast barium enema every 5 yr; 5) direct
colonoscopy every 10 yr
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| Fecal occult blood test: well studied; Minnesota trial—first of 5 randomized controlled studies to prove this modality effective
for screening for colon cancer; found that FOBT, followed by colonoscopy if positive, resulted in 45% reduction
in mortality from colorectal cancer; Danish study—screened every other year; concluded FOBT screening reduces colorectal
cancer mortality by ≈30%; advantages—detects most colorectal cancers and many advanced adenomas; reduces
colorectal cancer mortality; feasible and widely available; acceptable to patients; low up-front cost (cost-effective);
comment—combination of FOBT and FS “powerful way to screen”
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| Sigmoidoscopy: inspects that portion of colon where ≥70% of polyps and cancers arise; safe and acceptable; done in ≈5
min; feasible; bowel preparation simple; relatively inexpensive; effective and cost-effective; VA study concluded FS can
detect 70% of all cancers and polyps if probe goes to mid descending colon
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| Combination of annual FS and FOBT every 5 yr: strongly favored by speaker; FOBT insensitive to smaller polyps that do
not bleed and for distal cancers; FS misses ≈30% of lesions (above reach of scope); doing both tests largely compensates
for limitations of each done alone
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| Barium enema: seldom used for screening anymore; far less sensitive and specific than colonoscopy for detecting neoplasia;
5-yr interval appropriate
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| Colonoscopy: most effective method for detecting early cancers and advanced adenomas; diagnostic and therapeutic, as adenomas
removed at time of detection; has acceptable safety record if done by experienced examiner; perforation serious
but uncommon complication; infrequent screening possible (guidelines recommend use every 10 yr); cost-
effective; accuracy for detecting polyps >1 cm (according to 2 studies) 94% to 100%; however, study (done at University
of Wisconsin) found that 12% of polyps >1 cm missed on colonoscopy, when compared to virtual colonoscopy
(computed tomography [CT] colonography); therefore, colonoscopy not gold standard; detection best (95% to 98%)
when performed by experienced gastroenterologist
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| Status of colonoscopy: first recommended as screening option in 1997; proposed as preferred method of screening by
American College of Gastroenterology in 2000; became reimbursable by Medicare for people >65 yr of age in 2001;
United States National Polyp Study concluded it reduces cancer incidence by 76% to 90% by removing polyps; no randomized
trials, but good indirect evidence for effectiveness
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| Advantages: detects early cancer and advanced adenomas; limitations and concerns—risks; cost (not inexpensive procedure);
compliance; not available everywhere
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| Speaker’s preferences: screening colonoscopy preferred if resources allow; combination of FOBT and FS excellent alternative;
comments—best screening test is one patient actually does; unacceptable not to screen
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| Cost-effectiveness: colorectal cancer screening highly cost-effective (≈$15,000 per year of life saved); compares favorably
to hypertension management and better than mammography or lipid detection and management
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| Medicolegal issues: if guidelines followed, one can protect self from medicolegal claim; offer colorectal screening to all
asymptomatic average-risk patients >50 yr of age, and document in chart if they accept or decline; identify high-risk patients,
especially those with significant family histories; refer all patients with positive FOBT for colonoscopy; FOBT
done as part of digital rectal examination (DRE) not recommended (if done and positive, do colonoscopy; if negative, follow
with at-home sample collection)
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| Special points: definitive diagnostic evaluation (not screening) indicated for symptomatic patients; discontinue screening
when likely not of benefit, due to comorbidity or advanced age (speaker generally stops screening at ≈80 yr of age); generally
offer patients 1 or 2 screening options; compliance with screening recommendations reduces colorectal cancer mortality
by >50%
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| PROSTATE CANCER—Warren A. Jones, MD, Distinguished Professor of Health Policy, University of Mississippi
School of Medicine, Jackson, and Past President, American Academy of Family Physicians (AAFP)
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| Prevalence: in United States, prostate cancer affects 1 in 6 men; ≈30,000 men annually die from this malignancy; however,
more men die with this cancer than from it
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| Forms of cancer: not all prostate cancers alike; some aggressive, while others slow growing and remain indolent for years;
tests currently not available to determine virulence of particular cancers
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| Detection of prostate tumors: since 8 in 10 tumors localized when diagnosed, early detection important; diagnosis in early
stages often associated with excellent 5-yr survival; comments—5-yr survival for all stages of prostate cancer dramatically
increased since 1985, due to earlier detection and more targeted interventions
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| Risk factors: ethnicity (blacks worldwide have >2:1 ratio of prostate cancer, compared to whites); age (75% of tumors
found in men >65 yr of age); positive family history (plays significant role; men with family history of close relatives
with prostate cancer at <60 yr of age at particularly high risk); high-fat diet; genetics (susceptibility can be inherited; 5%-
10% of cases hereditary)
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| Role of screening: controversial; AAFP recommends that decision be made by physician in consultation with patient, ie,
screening recommended after dialogue and exchange between family physician and patient
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| Screening: generally begins at 50 yr of age; in blacks and other high-risk men, consider starting screening at 40 to 45 yr of
age; do both DRE and prostate-specific antigen (PSA)
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| Prostate-specific antigen: elevated in conditions other than cancer (eg, benign prostatic hyperplasia [BPH], urinary tract
infections [UTIs], prostatitis, other infections); basal level tends to be higher in blacks than in whites; false-positive
finding in absence of patient dialogue may result in unnecessary worry, complications of unnecessary procedures, and
impairment of quality of life; PSA levels may be artificially low, eg, in BPH patients on finasteride (adjustments required);
if PSA high, repeat test in 6 to 10 wk; studies show biphasic pattern of PSA levels in individuals; remark—
various PSA components (eg, PSA density; age-specific PSA measurements; PSA velocity; percentage of free PSA)
helpful in further evaluating patient
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| PSA milestones: PSA <4 ng/mL considered normal (but some men with levels in this range progress to prostate cancer);
PSA 4 to 10 ng/mL associated with ≈20% to 30% risk for cancer; those with PSA between 10 and 20 ng/mL have 50%
to 75% risk for cancer; PSA >20 ng/mL indicative of frank cancer
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| Transurethral ultrasonography: indicated if DRE indicates questionable lesion and/or PSA elevated; helpful in identifying
areas of concern
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| Presence of symptoms: with PSA screening, many cancers found long before symptoms develop; symptoms to ask about
include hesitancy, dribbling, dysuria, urinary retention, painful ejaculation, low back pain, pain with bowel movements,
excessive nocturnal urination, incontinence, bone pain and tenderness, hematuria, abdominal pain, anemia, unintended
weight loss, and lethargy
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| Transurethral resection of prostate (TURP): something to consider if ultrasonography suggests patient has BPH; reduces
prostate mass and PSA
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| Management of prostate cancer: includes everything from watchful waiting to significant invasive procedures; clinical
evaluation should help decide which modality fits best for patient; factors to consider in determining type of therapy include
patient’s age, general health, clinical staging, histology, quality-of-life issues, and treatment-related risk factors;
merge Gleason scale for histologic component with tumor, node, metastases (TNM) system for clinical staging
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| Management: watchful waiting—sometimes indicated if dealing with indolent slow-growing tumor; close monitoring required;
surgery—includes radical prostatectomy, nodal dissection, and laparoscopic procedures; goal to eliminate tumor
while trying to retain normal urinary and sexual function; radiation therapy—intensity-modulated radiation therapy
(IMRT) targets radiation to prostate and avoids surrounding tissues; brachytherapy (ultrasound-guided placement of radioactive
seeds into prostate) useful for managing low-grade lesions; studies now being done on short-term placement of
high-dose radiation seeds and IMRT in patients with more advanced stages of prostate cancer (results so far promising);
hormonal therapy—done in cyclic process and usually coupled with orchiectomy or androgen inhibition; use highly correlated
with impotence; chemotherapy—indicated when dealing with widespread tumor metastasis
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| Complications of management: significant; therefore, physician needs to do 3 critical things, 1) make sure screening done
correctly, 2) work with patients on various options, and 3) confer with referral colleagues to determine how best to manage
patients
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| Areas of ongoing research: earlier identification and differentiation of indolent and aggressive cancer; early identification
and treatment of tumors; providing better quality of life for patients and their families
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| Posttreatment monitoring: essential; best done by following PSA; PSA rise suggests recurrence of cancer
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| Studies: recent Swedish study—suggests low-risk men may get away with PSA screening as infrequently as once every 3
yr; recent New England Journal of Medicine article—reports new protein antibody may be more specific for prostate
cancer than elevated PSA
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| Complementary and alternative medicine (CAM): used by many patients to treat prostate cancer; pomegranate reported
to slow growth of prostate cancer cells; ask patients if they are engaging in CAM, as it may affect outcomes of medical
and surgical interventions
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| Key steps: 1) make patients aware of all options before and after treatment for prostate cancer; 2) make sure follow-up visits
scheduled and adhered to; 3) advise patients they are not fighting prostate cancer alone and that support groups available
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| Other steps: 1) obtain documentation for all referrals; 2) encourage patients to be proactive in keeping meaningful records
and documentation on what happens to them; 3) encourage patients to keep record of type of cancer and form of treatment;
4) advise patients to maintain contact information about others who have provided care for them; 5) have documentation
of level of supportive care required; 6) ask patients to maintain records of significant health problems and to
take with them when they move elsewhere
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| Controversies concerning prostate cancer: 1) screening (eg, when should it occur, for whom it should be offered, for
whom it should be insisted on); 2) management (eg, benefits vs side effects of medical and surgical interventions); 3)
failure to help patients determine what should be done
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Educational Objectives
| The goal of this program is to educate the listener about screening and management options for colorectal cancer and prostate
cancer. After hearing and assimilating this program, the clinician will be better able to:
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| 1. Understand the benefits and limitations of the various options for colorectal cancer screening (eg, fecal occult blood
test, flexible sigmoidoscopy, double-contrast barium enema, colonoscopy, virtual colonoscopy).
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| 2. Recognize the diagnostic and therapeutic benefits of colonoscopy.
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| 3. Realize that both colorectal and prostate cancer tend to run in families (ie, genetic component).
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| 4. Advise patients that both digital rectal examination (DRE) and prostate-specific antigen (PSA) are important in
screening for prostate cancer.
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| 5. Inform patients about the various options available for managing prostate cancer, depending on its degree of virulence
(eg, watchful waiting, radical prostatectomy, radiation therapy).
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Discussed on This Program
Finasteride [Propecia, Proscar]
Suggested Reading
Abir F et al: The management of rectal cancer in the elderly. Surg Oncol 13:223, 2004; Azzouz H, de la Rosette JJ: Radical
prostatectomy in high-risk prostate cancer. Can J Urol 12(Suppl 2):33, 2005; Benjamin R: Neurologic complications
of prostate cancer. Am Fam Physician 65:1835, 2002; Beyer DC: Salvage brachytherapy after external-beam irradiation
for prostate cancer. Oncology 18:151, 2004; Bhatnagar V, Kaplan MK: Treatment options for prostate cancer: evaluating
the evidence. Am Fam Physician 71:1915, 2005; Bond JH: Are fecal occult blood testing and flexible sigmoidoscopy adequate
for colorectal cancer screening? Seminars in Colon and Rectal Surg 11:2, 2000; Haug U, Brenner H: New stool
test for colorectal cancer screening: a systematic review focusing on performance characteristics and practicalness. Int J
Cancer 117:169, 2005; Katz ML et al: Prostate and colon cancer screening messages in popular magazines. J Gen Intern
Med 19:843, 2004; Lieberman DA et al: Use of colonoscopy to screen asymptomatic adults for colorectal cancer. N Engl
J Med 343:162, 2000; Lillis P, Thompson IM, Jr: Should asymptomatic progression following definitive local treatment
for prostate cancer be treated? Hematol Oncol Clin North Am 10:703, 1996; Mandel JS, Bond JH et al: Reducing mortality
from colorectal cancer by screening for fecal occult blood. N Engl J Med 328:1365, 1993; Mandel JS, Bond JH et al:
The effect of fecal occult blood screening on the incidence of colorectal cancer. N Engl J Med 343:1603, 2000; Mulhall BP
et al: Metaanalysis: computed tomographic colonography. Ann Intern Med 142, 2005; Naitoh J et al: Diagnosis and treatment
of prostate cancer. Am Fam Physician 57:1531, 1998; Nasr R, Goldenberg SL: Rising prostate specific antigen after
radical prostatectomy: a case based review. Can J Urol 8:1306, 2001; Nichol AM et al: Optimal treatment of intermediate-
risk prostate carcinoma with radiotherapy: clinical and translational issues. Cancer 104:891, 2005; Smith RA et al: American
Cancer Society guidelines for the early detection of cancer: update of early detection guidelines for prostate, colorectal,
and endometrial cancers. CA Cancer J Clin 51:38, 2001; Tiguert R et al: Radiation therapy for a rising PSA level after
radical prostatectomy. Semin Urol Oncol 17:141, 1999; Trabulsi EJ, Guillonneau B: Laparoscopic radical prostatectomy.
J Urol 173:1072, 2005; Wilson SS, Crawford ED: Screening for prostate cancer: current recommendations. Urol Clin
North Am 31:219, 2004; Winawer SJ, Bond JH et al: Colorectal cancer screening and surveillance: clinical guidelines and
rationale—update based on new evidence. Gastroenterology 124:544, 2003; Woolf SH, Krist A: The liability of giving
patients a choice: shared decision making and prostate cancer. (Editorial) Am Fam Physician 71:1871, 2005; Zuber RJ:
Flexible sigmoidoscopy. Am Fam Physician 63:1375, 2001.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial relationship
with the manufacturer or provider of any commercial product or service discussed. For this issue, the faculty reported
nothing to disclose.
Dr. Bond was recorded on May 23, 2005, at the Annual Family Practice Review, sponsored by the University of Minnesota
Medical School, Minneapolis. Dr. Jones spoke on September 29, 2005, at the Annual Scientific Assembly of
the American Academy of Family Physicians, held in San Francisco. The Audio-Digest Foundation thanks the speakers
and the sponsors for making this program possible.
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