Elderly Man With Weakness, Poor Appetite, and Abdominal Cramping on Defecation

An 83-year-old man complains of weakness, easy fatigability, and poor appetitethat began 4 to 6 weeks ago. He becomes short of breath on his daily walksand has lost about 20 pounds over the last 3 months. He denies nocturia,paroxysmal nocturnal dyspnea, exertional chest pain, fever, cough, melena,and hematochezia. His only GI symptom is occasional crampy abdominal painwith bowel movements.

HISTORY
The patient had squamous cell carcinoma of the esophagus 15 years agoand underwent a resection, chemotherapy, and radiation therapy. Since the resection,he has had intermittent strictures that require dilation; his last dilationwas 18 months ago. He has an esophagogastroduodenoscopy (EGD) every 6months; his last EGD, done 5 months ago, revealed Barrett esophagus but nostrictures. The patient stopped smoking and drinking at the time of his treatmentfor esophageal carcinoma; he had previously smoked 2 packs per day for40 years and had several drinks daily.

PHYSICAL EXAMINATION
This elderly man is frail and thin. He is afebrile, and his blood pressure is160/70 mm Hg. Mucous membranes are moist; pharynx is not erythematous.Conjunctiva are pale. Lungs are clear, and heart is normal. Neck is withoutbruits, lymphadenopathy, or masses. Abdomen is soft and nontender; noorganomegaly is noted. The patient denies dysphagia, odynophagia, reflux,and heartburn. A rectal examination reveals heme-positive stool but no palpablemasses. There is no clubbing or edema of the extremities.

LABORATORY RESULTS
Hemoglobin level is 8.1 g/dL; hematocrit, 23.7 mL/dL; and mean corpuscularvolume (MCV), 69.9 fL. Red blood cell distribution width (RDW) index is17.8%. Total bilirubin level is 0.1 mg/dL; blood urea nitrogen level, 21 mg/dL;and creatinine level, 1.3 mg/dL. Five months ago, the patient's hemoglobinlevel was 13.7 g/dL and his MCV was 84 fL.

Which of the following studies will be most helpful in arrivingat a diagnosis?A. Ferritin level, transferrin level, and total iron-binding capacity toconfirm iron deficiency.
B. Barium swallow.
C. EGD.
D. Colonoscopy.
E. Flexible sigmoidoscopy.

CORRECT ANSWER: D
This patient is severely anemic and has heme-positivestool. The anemia, low MCV, and elevated RDW index arerecent and are suggestive-if not diagnostic-of iron deficiency.Further iron studies (choice A) would most likelyconfirm iron deficiency but would not aid in identifyingthe cause.

Iron deficiency anemia in a man or a postmenopausalwoman usually results from pathologic blood loss. TheGI tract is the most common site of chronic blood loss;causes can include peptic ulcer disease, polyps, diverticula,and carcinomas.¹

A barium swallow (choice B) facilitates noninvasiveevaluation of swallowing and esophageal anatomy. Thisstudy can revealdysmotility oreven a mass butcannot showactive bleeding.Furthermore,this patient hashad no complaintsof dysphagiaor symptomsof other esophagealdisease,such as a motilitydisorder. Thus, abarium swallowwould be unlikelyto reveal usefulinformation.

An EGD(choice C) canreveal esophagealbleeding (as well as such gastric and duodenal lesionsas ulcers and tumors). However, this patient's mostrecent EGD showed a proximal stricture and Barrettesophagus but no inflammation or bleeding. Moreover, hehas none of the typical symptoms of an esophageal mass,such as dysphagia. Thus, it is unlikely that a malignancywould have occurred since the time of his last EGD.

Because the patient's only GI symptom is crampingassociated with bowel movements, focus your initialinvestigation on the lower GI tract.¹ A flexible sigmoidoscopy(choice E) is good at detecting more distal GIlesions. However, many proximal tumors can be missedusing this test.²

The American Cancer Society recommends colonoscopy(choice D) for patients older than 50 years whohave a positive fecal occult blood test. Colonoscopy is consideredthe most accurate test for the detection of coloniclesions.³ Disputes about the merits of colonoscopy as ascreening test center on the higher cost and lower levelsof patient compliance than those seen with flexible sigmoidoscopyand/or stool testing.

During this patient's colonoscopy, a fungating mass5 cm in circumference, causing partial obstruction, wasfound 8 cm from the anal verge. Pathologic analysis revealedadenocarcinoma of the sigmoid colon.

The patient underwent resection of the lesion-aDukes B₂ carcinoma. He was doing well 10 months aftersurgery; his anemia resolved, and he had no GI symptoms.In light of his advanced age, a mutual decision wasmade to withhold neoadjuvant chemotherapy.

References:

REFERENCES:1. Rockey DC, Cello JP. Evaluation of the gastrointestinal tract in patients withiron deficiency anemia. N Engl J Med. 1993;329:1691-1695.
2. Lieberman DA, Weiss DG. One-time screening for colorectal cancer withcombined fecal occult-blood testing and examination of the distal colon. N Engl JMed. 2001;345:555-560.
3. Ransohoff DF, Sandler RS. Screening for colorectal cancer. N Engl J Med.2002;346:40-44.