CANCER OF THE PANCREAS
The incidence of pancreatic cancer has decreased slightly over the past 25 years in non-Caucasian men. It is the fifth leading cause of cancer deaths in the United States and occurs most frequently in the fifth to seventh decades of life (American Cancer Society, 2002). Cigarette smoking, exposure to industrial chemicals or toxins in the environment, and a diet high in fat, meat, or both are associated with pancreatic cancer, although their role is not completely clear. The risk for pancreatic cancer increases as the extent of cigarette smoking increases. Diabetes mellitus, chronic pancreatitis, and hereditary pancreatitis are also associated with pancreatic cancer. The pancreas can also be the site of metastasis from other tumors.
Cancer may arise in any portion of the pancreas (in the head, the body, or the tail); clinical manifestations vary depending on the location of the lesion and whether functioning, insulin-secreting pancreatic islet cells are involved. Approximately 75% of pancreatic cancers originate in the head of the pancreas and give rise to a distinctive clinical picture. Functioning islet cell tu-mors, whether benign (adenoma) or malignant (carcinoma), are responsible for the syndrome of hyperinsulinism. With these ex-ceptions, the symptoms are nonspecific, and patients usually do not seek medical attention until late in the disease; 80% to 85% of patients have advanced, unresectable tumor when first detected. In fact, pancreatic carcinoma has only a 2% to 5% survival rate at 5 years regardless of the stage of disease at diagnosis or treat-ment (Tierney et al., 2001).
Pain, jaundice, or both are present in more than 90% of patients and, along with weight loss, are considered classic signs of pan-creatic carcinoma. However, they often do not appear until the disease is far advanced. Other signs include rapid, profound, and progressive weight loss as well as vague upper or midabdominal pain or discomfort that is unrelated to any gastrointestinal func-tion and is often difficult to describe. Such discomfort radiates as a boring pain in the midback and is unrelated to posture or ac-tivity. It is often progressive and severe, requiring the use of opi-oids. It is often more severe at night. Relief may be obtained by sitting up and leaning forward, or accentuated when lying supine.
Malignant cells from pancreatic cancer are often shed into the peritoneal cavity, increasing the likelihood of metastasis. The for-mation of ascites is common. An important sign, when present, is the onset of symptoms of insulin deficiency: glucosuria, hyper-glycemia, and abnormal glucose tolerance. Thus, diabetes may be an early sign of carcinoma of the pancreas. Meals often aggravate epigastric pain, which usually occurs before the appearance of jaundice and pruritus.
Magnetic resonance imaging and computed tomography are used to identify the presence of pancreatic tumors. ERCP is also used in the diagnosis of pancreatic carcinoma. Cells obtained during ERCP are sent to the laboratory for examination. Gastrointestinal x-ray findings may demonstrate deformities in adjacent viscera caused by the impinging pancreatic mass.
Percutaneous fine-needle aspiration biopsy of the pancreas is used to diagnose pancreatic tumors and confirm the diagnosis in patients whose tumors are not resectable, eliminating the stress and postoperative pain of ineffective surgery. In this procedure, a needle is inserted through the anterior abdominal wall into the pancreatic mass, guided by computed tomography, ultrasound, ERCP, or other imaging techniques. The aspirated material is ex-amined for malignant cells. Although percutaneous biopsy is a valuable diagnostic tool, it has some potential drawbacks: a false-negative result if small tumors are missed and seeding of cancer cells along the needle track. Low-dose radiation to the site may be used before the biopsy to reduce the risk of seeding.
Percutaneous transhepatic cholangiography is another proce-dure that may be performed to identify obstructions of the bil-iary tract by a pancreatic tumor. Several tumor markers (eg, CA 19-9, CEA, DU-PAN-2) may be used in the diagnostic workup, but they are nonspecific for pancreatic carcinoma. These tumor markers are useful as indicators of disease progression.
Angiography, computed tomography, and laparoscopy may be performed to determine whether the tumor can be removed surgically. Intraoperative ultrasonography has been used to de-termine if there is metastatic disease to other organs.
If the tumor is resectable and localized (typically tumors in the head of the pancreas), the surgical procedure to remove it is usually ex-tensive (see Medical Management in Tumors of the Head of the Pancreas). However, definitive surgical treatment (ie, total excision of the lesion) is often not possible because of the extensive growth when the tumor is finally diagnosed and because of the probable widespread metastases (especially to the liver, lungs, and bones). More often, treatment is limited to palliative measures.
Although pancreatic tumors may be resistant to standard ra-diation therapy, the patient may be treated with radiation and chemotherapy (fluorouracil and gemcitabine). If the patient un-dergoes surgery, intraoperative radiation therapy (IORT) may be used to deliver a high dose of radiation to the tumor with mini-mal injury to other tissues. IORT may also be helpful in relief of pain. Interstitial implantation of radioactive sources has also been used, although the rate of complications is high. A large biliary stent inserted percutaneously or by endoscopy may be used to re-lieve jaundice.
Pain management and attention to nutritional requirements are important nursing measures to improve the level of comfort. Skin care and nursing measures are directed toward relief of pain and discomfort associated with jaundice, anorexia, and profound weight loss. Specialty mattresses are beneficial and protect bony prominences from pressure. Pain associated with pancreatic can-cer may be severe and may require liberal use of opioids; patient-controlled analgesia should be considered for the patient with severe, escalating pain.
Because of the poor prognosis and likelihood of short survival, end-of-life preferences are discussed and honored. If appropriate, the nurse refers the patient to hospice care. (See Chaps. 16 and 17, respectively, for discussion of care of the patient with cancer and end-of-life care.)
The specific patient and familyteaching indicated varies with the stage of disease and the treat-ment choices made by the patient. If the patient elects to receive chemotherapy, the nurse focuses teaching on prevention of side effects and complications of the agents used. If surgery is per-formed to relieve obstruction and establish biliary drainage, teach-ing addresses management of the drainage system and monitoring for complications. The nurse instructs the family about changes in the patient’s status that should be reported to the physician.
A referral for home care is indicated to help thepatient and family deal with the physical problems and discom-forts associated with pancreatic cancer and the psychological im-pact of the disease. The home care nurse assesses the patient’s physical status, fluid and nutritional status, and skin integrity and the adequacy of pain management. The nurse teaches the patient and family strategies to prevent skin breakdown and relieve pain, pruritus, and anorexia. It is important to discuss and arrange pal-liative care (hospice services) in an effort to relieve patient dis-comfort, assist with care, and comply with the patient’s end-of-life decisions and wishes.