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Lymph Node Cancer

Surgical treatment of breast cancer is rapidly evolving, and advances in surgical technology as well as the development of minimally invasive surgical techniques have heralded a new era in surgery. Sentinel lymph node biopsy is one of the new technologies that must meet today's challenges of improving efficiency and reducing patient risk at diminished cost and resource utilization.(1)

WHAT IS SENTINEL LYMPH NODE BIOPSY?

The lymphatic system disseminates fluids and proteins throughout the body to prevent swelling. Acting as a filter, the system also serves as a conduit for cancer cells to flow from a primary tumor to other sites in a particular body region. The sentinel node is the first lymph node in a regional lymphatic basin to receive lymphatic drainage from a primary tumor; therefore, it is the first lymph node encountered by tumor cells metastasizing through the lymphatic channels.(2) For the breast, the sentinel lymph node is located in the axillary region of the effected side.

Sentinel lymph node biopsy is a diagnostic procedure used to determine the status of regional lymph nodes for staging purposes. The sentinel lymph node can be located precisely for surgical excision and pathological examination by injecting a blue dye and radioactive isotope around the primary tumor. As the sentinel lymph node is most likely to harbor a concentrated amount of metastases, a more focused histologic analysis is made possible, and the tumor status of this node will reflect the tumor status of the entire basin.(3)

The technique first was described in 1977 and was popularized in the mid 1980s and early 1990s by physicians studying melanoma.(4) Since the late 1990s, sentinel lymph node biopsy for patients with breast carcinoma has been studied to validate cancer stages to predict patients' survival, outcomes, and the necessity for further adjuvant therapy or radiotherapy.(5)

WHY USE SENTINEL LYMPH NODE BIOPSY?

The purpose of sentinel lymph node biopsy is to accurately predict metastases or diagnose stages of cancer without having to perform a complete axillary dissection. Lumpectomy for tumor removal remains a necessity and accompanies the sentinel lymph node biopsy; however, axillary dissection may be eliminated for many patients. Determining the presence of metastatic involvement in the axillary nodes is of paramount importance and remains the most powerful predictor of survival and recurrence. For patients with early stage breast cancer, the nodal status is the most important prognostic factor in determining future adjuvant therapy or radiotherapy.(6)

According to conventional pathological methods, approximately 40% of all patients with operable breast cancer have axillary disease and require complete removal of all lymph nodes.(7) This statistic may be reduced to 30% when earlier detection methods are used. By using the sentinel lymph node biopsy method to detect the presence or absence of metastases of cancer cells to the lymph nodes, approximately 55% to 70% of patients undergoing sentinel lymph node biopsy may be spared possible complications from axillary dissection. These complications include

* pain,

* paresthesia,

* lymphedema,

* seroma,

* infection, and

* limited or disabling shoulder motion.

As sentinel lymph node biopsy is less invasive, patient morbidity and the facility's cost and resource utilization are lower when biopsy results are negative.(8)

IDEAL CANDIDATES

Patients presenting in the OR for sentinel lymph node biopsy have carcinoma of the breast confirmed by a needle biopsy performed in a physician's office or by an excisional biopsy performed in an OR. Patients selected for the sentinel lymph node biopsy procedure typically are women with small, single primary tumors (ie, less than 5 cm). The tumor may be palpable or nonpalpable. Contraindications include pregnancy, allergy to blue dye or radioactive colloid, palpable axillary node mass, multifocal breast cancer, and previous major breast or axillary procedures that may distort lymphatic drainage.(9)

TREATMENT LOCATION

The sentinel lymph node biopsy procedure typically takes place in an outpatient setting. Patients who are diagnosed after the biopsy with negative sentinel lymph nodes usually are discharged the day of surgery, after a safe response and recovery from anesthesia. Those with positive diagnoses who require axillary node dissection may remain overnight for observation. Any required nuclear medicine or radiology services occur before the surgical procedure on the same day. Preoperative teaching is initiated by the physician and his or her office staff members during the patient's office visit before hospital admission. This teaching includes information on preparing for a lumpectomy, sentinel lymph node biopsy, possible axillary dissection, isotope injection, and possible needle localization.

PREOPERATIVE PHASE

After arriving at the hospital, the patient visits the nuclear medicine and radiology departments. Only patients with nonpalpable tumors may require a needle localization to pinpoint the tumor site. These patients will visit the radiologist first for placement of a localization wire to help the surgeon identify the precise location of the tumor for excision. All patients then have a radioactive isotope injected into the breast by a nuclear medicine physician in the nuclear medicine department. The time and placement of the injection and the dosage and type of isotope depend on the location of the tumor, the injection method (eg, subdermal, parenchymal), and the scheduled time of the surgical procedure.(10) Drainage of the isotope to the lymphatic tissue is possible between 10 minutes and three hours after injection, and surgery is scheduled to occur within that time period.(11)

A typical isotope dose is only a fraction of the threshold for imposing radiation restrictions, and isotope exposure for surgeons, OR staff members, and pathologists is minimal. In addition, staff members' physiological excretions significantly reduce isotope levels, thus preventing the need for extensive radiation precautions.(12)

It is advantageous for the perioperative nurse to have knowledge of the sentinel lymph node biopsy procedure to appropriately answer patient questions. During the preoperative interview, the nurse should realize that the patient is aware of her positive cancer diagnosis and, therefore, may have more anxiety about the surgical procedure than patients with more routine diagnoses. It is important to remember that, at this point, the patient is facing a lumpectomy and sentinel lymph node biopsy with possible axillary dissection. The surgical consent should include all of these procedures for the patient's affected side. General anesthesia is preferred because axillary dissection may be indicated; therefore, the patient's NPO status and allergies must be accurately documented.

In the OR, the perioperative nurse must procure draping materials, instrumentation, suture, and irrigation solution for lumpectomy and possible axillary dissection, as preferred by the individual surgeon. Additional items needed are outlined in Table 1.

Table 1

INSTRUMENTATION FOR SENTINEL NODE BIOPSY

Gamma tracer probe, gamma counter, and sterile sleeve for probe

This is a tracking device for the isotope to locate its path in the
lymph system to the sentinel node. The probe is connected to a
counter (ie, a small electrical box approximately 8 inches x 10
inches x 10 inches) and is used to externally locate the area of
highest intensity in the lymph region (ie, the axilla for the
breast). This "hot spot" is assumed to be the sentinel node, thus
the surgeon makes a small, precise incision directly over this node.
A smaller incision minimizes tissue damage, postoperative pain, and
potential for infection. This tracking device also is used to verify
the presence of isotope in the excised node.

Isosulfan blue dye (5 mL) or sulfan blue (Patent Blue V) (0.5 mL),
one small syringe and 25-g needle, alcohol wipe, and nonsterile
gauze sponge

The blue dye is injected by the surgeon at the tumor site after the
patient is intubated. The dye is transported by the lymph system and
drains to the sentinel node. With dissection, the node is located
easily due to its blue color.

Extra pathology department containers and request forms

The circulating nurse should be prepared with enough containers
and request forms from the pathology department to handle up to five
specimens. The sentinel node biopsy may include two specimens and is
sent immediately to the pathology department for analysis. Specimens
from the lumpectomy and axillary dissection may or may not be placed
in formaldehyde for transport to the pathology department, according
to the surgeon's preference.

INTRAOPERATIVE PHASE

The patient is transferred to the OR and placed in the supine position with the arm of the affected side secured on a padded arm board at just less than 90 degrees. After anesthesia induction, the surgeon injects the blue dye around the tumor five minutes before the incision is made. The circulating nurse hand massages the injection site for approximately one to two minutes. Hand massage expedites the uptake of the blue dye by the lymph system. In the case of a nonpalpable tumor, the dye is injected around the site of the needle localization wire.(13)

The anesthesia care provider may notice a false drop of approximately five points in the patient s oxygen saturation reading, as this is a side effect of the dye.(14) Methylene blue should not be used because its particles are too small to be picked up reliably by the lymph nodes. Use of dye in combination with the isotope is preferable, especially during the surgeon's training period, because neither the dye nor the isotope is 100% successful when used alone.(15)

The nurse preps the patient's breast, chest, axilla, and upper arm with the surgeon's solution of choice and drapes the patient to expose these areas. The surgeon uses the gamma probe connected to the gamma counter with the sterile sleeve intact to locate the sentinel lymph node, which usually is under the patient's arm just below the hairline. The surgeon passes the probe over the skin and makes an incision in the area that produces the highest reading. Dissection to the fascia follows, and the node is located and removed using the injected blue dye as an internal map. The surgeon then passes the probe over the excised tissue and records the reading. The nurse labels the specimen with the patient's information and immediately forwards it to the pathology department for a frozen section analysis that includes the use of special antibodies to identify metastases. The surgeon passes the probe over the surgical site again and excises more specimen if elevated radioactive readings continue to occur. The average number of sentinel lymph nodes for a patient with breast cancer is 1.2 to 1.8; therefore, occasionally more than one sentinel lymph node may be excised and analyzed.(16)

The surgeon proceeds with the lumpectomy during the sentinel lymph node analysis. The nurse labels the lumpectomy specimen with the patient's information. The specimen may or may not be placed in formaldehyde before it is sent immediately to the pathology department for examination of adequate margins around the tumor excision.

After determining the status of the sentinel lymph node and lumpectomy, the pathologist will communicate the results directly to the surgeon in the OR. Axillary dissection will proceed through the sentinel lymph node incision only if the sentinel lymph node is positive for carcinoma. After completion, the nurse labels the axillary mass with the patient's information. As with the lumpectomy specimen, this specimen may or may not be placed in formaldehyde before it is sent immediately to the pathology department for further analysis.

The surgeon then irrigates the wounds, places a flat or round drain with a small reservoir in the axilla, and closes the incisions at the axilla and lumpectomy sites. The nurse dresses and secures the wounds according to surgeon preference and transports the patient to the postanesthesia care unit (PACU).

Ensuring radioactive safety. In the OR, all used instrumentation is secured in a plastic bag before being transported to the contaminated utility area. Other used materials are secured in plastic and disposed of in accordance with the hospital's policies and procedures. Radiation detected in the used instrumentation, linen, and trash may be monitored to ensure that radioactive levels are safe. This is achieved in the OR by passing the gamma probe over these items before they are disposed of and reporting the radioactive levels if they are above a predetermined amount. The amount can be determined by a hospital committee that oversees the sentinel biopsy program and includes members from all departments who are directly and indirectly involved with patient care. In addition, laboratory specimens are labeled as radioactive to alert transporters and laboratory staff members that some radioactivity is present.

POSTOPERATIVE PHASE

The anesthesia care provider's report to the PACU nurse includes the patient's vital signs, medications received, and overall response to anesthesia. The circulating nurse's report includes the procedures performed, the presence of dressings and drains, the presence or absence of drainage from surgical sites, and the possibility of a blue appearance to the patient's skin from the-spread of blue dye throughout the lymphatic system. The PACU nurse also is informed that the patient's urine may be green as a result of the blue dye and its physiologic breakdown in the body. The amount of time spent in the PACU varies for each patient and depends on the patient's response to anesthesia. The PACU nurse issues postoperative instructions to the patient and his or her family members and obtains admit or discharge orders from the surgeon.

The patient is instructed about the presence of the drain, which is to remain in place until the patient revisits the surgeon in approximately one week. At that time, the drain is removed if exudate is absent. The patient is instructed to avoid wetting or immersing the skin area around the drain until it is removed and to avoid heavy lifting for several weeks. Dressings are removed within 24 hours after surgery, and the surgical site may be cleaned with a sponge. Small dry dressings should remain on the drain sites and be changed daily as part of the patient's bathing routine.

SUCCESS AS A TEAM EFFORT

Successful sentinel lymph node biopsy involves quality control and a concerted effort among the nuclear medicine physician, radiologist, surgeon, and pathologist.(17) The technique is dependent on the surgeon to locate the correct node and the thoroughness of the pathologist's examination. Clinical trials must use similar protocols to interpret positive results.(18) Training in the method should include formal courses and hands-on components monitored by experienced surgeons. Most surgeons perform a series of procedures with sentinel lymph node biopsy and axillary dissection to master their technique. On average, this combination method is performed on 10 to 30 patients before the sentinel lymph node biopsy procedure is performed without axillary dissection.(19)

The most important factor of sentinel lymph node biopsy is prevention of a false negative (ie, axillary metastases and a negative sentinel lymph node). This situation not only results in an incorrect diagnosis, but also has a negative impact on further treatment decisions.(20)

SUMMARY

Although sentinel lymph node biopsy is not yet considered standard care for breast cancer by physician groups, multicenter trials continue to yield positive statistics and support the expanding applicability of the protocol. Perioperative nurses, therefore, should be prepared for the development of this technique. To provide the best opportunity for an optimum sentinel lymph node biopsy, timing is of utmost importance. As a result, hospital size and physical location of the ORs and the radiology, nuclear medicine, and pathology departments affect the specific implementation of this program for each hospital. Key elements and standard research protocols approved by advisory boards must remain constant to ensure program integrity and appropriately tracked outcomes.(21)

NOTES

(1.) C E Cox et al, "Implementation of new surgical technology: Outcome measures for lymphatic mapping of breast carcinoma," Annals of Surgical Oncology 6 (September 1999) 553-561.

(2.) K M McMasters et al, "Sentinel-lymph-node biopsy for breast cancer--not yet the standard of care," The New England Journal of Medicine 339 (Oct 1, 1998) 990-995; A D Hill et al, "Sentinel lymphatic mapping in breast cancer," Journal of American College of Surgeons 188 (May 1999) 545-549.

(3.) McMasters et al, "Sentinel-lymph-node biopsy for breast cancer--not yet the standard of care," 990-995; E C Hsueh et al, "Sentinel node biopsy in breast cancer," Journal of American College of Surgeons 189 (August 1999) 207-213.

(4.) McMasters et al, "Sentinel-lymph-node biopsy for breast cancer--not yet the standard of care," 990-995; Hill et al, "Sentinel lymphatic mapping in breast cancer," 545-549; N Beechey-Newman, "Sentinel node biopsy: A revolution in the surgical management of breast cancer?" Cancer Treatment Reviews 24 (June 1998) 185-203.

(5.) McMasters et al, "Sentinel-lymph-node biopsy for breast cancer--not yet the standard of care," 990-995; Hill et al, "Sentinel lymphatic mapping in breast cancer," 545-549.

(6.) McMasters et al, "Sentinel-lymph-node biopsy for breast cancer--not yet the standard of care," 990-995; Hsueh et al, "Sentinel node biopsy in breast cancer," 207-213; Beechey-Newman, "Sentinel node biopsy: A revolution in the surgical management of breast cancer?" 185-203.

(7.) Beechey-Newman, "Sentinel node biopsy: A revolution in the surgical management of breast cancer?" 185-203.

(8.) McMasters et al, "Sentinel-lymph-node biopsy for breast cancer--not yet the standard of care," 990-995; Hsueh et al, "Sentinel node biopsy in breast cancer," 207-213.

(9.) McMasters et al, "Sentinel-lymph-node biopsy for breast cancer--not yet the standard of care," 990-995.

(10.) "Key elements of sentinel node biopsy," in Oncology Roundtable Annual Meeting, Frontier Clinical Practice (Washington, DC: The Advisory Board Co, 1999) 27-29.

(11.) Beechey-Newman, "Sentinel node biopsy: A revolution in the surgical management of breast cancer?" 185-203.

(12.) Hill et al, "Sentinel lymphatic mapping in breast cancer," 545-549.

(13.) "Key elements of sentinel node biopsy," 27-29.

(14.) McMasters et al, "Sentinel lymph-node biopsy for breast cancer--not yet the standard of care," 990-995.

(15.) Hill et al, "Sentinel lymphatic mapping in breast cancer," 545-549.

(16.) Beechey-Newman, "Sentinel node biopsy: A revolution in the surgical management of breast cancer?" 185-203.

(17.) Hsueh et al, "Sentinel node biopsy in breast cancer," 207-213.

(18.) J D Pfeifer, "Sentinel-lymph-node biopsy," American Journal of Clinical Pathology 112 (November 1999) 599-602.

(19.) McMasters et al, "Sentinel-lymph-node biopsy for breast cancer--not yet the standard of care," 990-995; Hill et al, "Sentinel lymphatic mapping in breast cancer," 545-549.

(20.) Ibid; Cox et al, "Implementation of new surgical technology: Outcome measures for lymphatic mapping of breast carcinoma," 553-561; Hsueh et al, "Sentinel node biopsy in breast cancer," 207-213; Beechey-Newman, "Sentinel node biopsy: A revolution in the surgical management of breast cancer?" 185-203; Pfeifer, "Sentinel lymph node biopsy," 599-602.

(21.) "Key elements of sentinel node biopsy," 27-29.

Stephanie J. Kellar, RN, BSN, is a staff nurse, outpatient surgery, Baptist Hospital, Nashville.

The author acknowledges Pat W. Whitworth, MD, for his assistance in preparing this article.

COPYRIGHT 2001 Association of Operating Room Nurses, Inc.
COPYRIGHT 2001 Gale Group