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Adjuvant therapy is systemic therapy used for patients with local control (e.g., resection) who are at high risk of microscopic disease existing in lymph nodes or distant organs. A high proportion of these patients would develop recurrence at these sites, and adjuvant therapy attempts to destroy these distant, microscopic foci of cancer.

Multimodality therapy uses the advantages of each therapy to counteract the shortcomings of others. Examples follow:

Curable breast cancer. Surgery (mastectomy) or surgery (lumpectomy) plus radiation are used for local control. Surgery is used for staging of axillary lymph nodes, and postoperative chemotherapy is used for patients with positive malignancy in the nodes to decrease the chance of metastatic disease.

Pancoast tumor of the lung. Preoperative radiation is used for regional spread into the brachial plexus to decrease the tumor's size and to render the tumor surgically resectable.

Extremity sarcoma. Incisional biopsy is used for diagnosis; preoperative radiation therapy is used to decrease tumor size; radical local resection is used for initial local control; postoperative adjuvant radiation is used for further regional control; and chemotherapy is used for systemic control.

J Cancer surgery

The principles of cancer surgery are based on removing a tumor for cure. To prevent implantation of tumor cells at surgery, dissection is done through uninvolved tissue, staying away from the tumor. To prevent vascular dissemination, tumors are minimally manipulated, and the vascular pedicle is ligated early. To prevent lymphatic spread , the measures described previously are performed, plus the lymph node draining area is removed in continuity with the tumor.

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Curative resection. The several types of curative resection vary with the tumor's size, biologic behavior, and location.

Wide local resection is adequate for low -grade neoplasms that do not either metastasize to regional lymph nodes or deeply invade surrounding tissue. Examples include basal cell carcinoma of the skin or mixed tumor of the parotid gland.

Radical local resection is used for neoplasms that deeply invade surrounding tissue, e.g., extremity sarcoma where the resection includes the entire biopsy incision and the entire muscle compartment where the tumor lies.

Radical resection with en bloc excision of lymphatic drainage is used for tumors that usually first metastasize to regional lymph nodes (e.g., colon cancer where the segment of colon plus regional mesentery and lymphatics are removed as one specimen).

Super radical resections remove large portions of the body and are reserved for locally extensive disease with low likelihood of metastatic spread. Examples include pelvic exenteration removal of rectum, bladder, uterus [in women], and all pelvic lymphatics and soft tissues) for locally advanced cancers of the rectum, cervix, uterus, or bladder.

Staging procedures are used to establish the extent of disease to guide treatment.

Lymph node dissections for breast cancer and malignant melanoma are important for assessing prognosis and determining treatment. There is significant morbidity associated with lymph node dissection.

Sentinel lymph node excision is a less invasive, potentially equally accurate staging technique.

The tumor or just adjacent to the biopsy site is injected with a tracer , which is followed to the first lymph node draining the area.

The tracer can be a visible dye (isosulfan blue) or a radioactive tracer (technetium-99m[ 99 Tc]-labeled sulfur colloid) visualized with a hand-held gamma probe.

The sentinel node can be identified in about 95% of cases; however, excisional biopsies distort lymphatic drainage and lead to lack of success in identifying the node and also compromise the technique's accuracy.

The false -negative rate for sentinel node biopsy (negative sentinel node but other nodes in the same area positive) is less than 5%.

The diagnostic accuracy depends on precise pathology, often utilizing immunohistochemistry (see IV E 5).

Other surgical resections

Resection of recurrent cancer is occasionally feasible with localized recurrences. Examples include local (anastomotic) recurrence of GI cancer and local recurrence of skin cancer.

Resection of metastases is feasible in several circumstances. The two most common are isolated liver metastases from colon cancer and pulmonary metastases (especially from sarcomas sensitive to chemotherapy).

Palliative surgery is used to relieve or prevent a specific symptom of a cancer patient but without the intent to cure. An example is removal of an obstructing or bleeding colon cancer in a patient with liver metastases.

Debulking is the removal of the majority of a tumor, leaving residual disease. The rationale is that the remaining, smaller number of cancer cells will be more susceptible to chemotherapy or radiation therapy. It appears to be useful for advanced ovarian cancers.

Section B: Problems and Complications

V Postoperative Complications

Postoperative complications can be associated with any operation or can be related to a specific kind of surgery. The latter types are discussed in the relevant chapters, whereas general types of complications are discussed here. Thrombophlebitis and pulmonary embolus , which are common postoperative complications, are discussed briefly here and in detail in Chapter 8. Most surgical complications develop in relation to some event that occurs in the operating room, emphasizing the fact that prevention is the best form of management.

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A General principles of management

during the postoperative period are important both in preventing potential complications and in allowing early detection of problems that do develop. These principles include:

Daily or more frequent examination of the patient , including the surgical wound.

Removal of all surgical tubes as soon as possible.

Early ambulation of the patient.

Close monitoring of fluid balance and electrolyte levels.

Adequate but not excessive pain medication.

Good nursing care.

B

Postoperative fever occurs in typical patterns, and the “5W's” mnemonic is useful

W ind. Pulmonary complications, which typically occur earliest, on postoperative days 1–3.

Atelectasis is the usual problem and is treated with coughing, deep breathing, ambulation, and incentive spirometry. Antibiotics should not be given unless evidence of infection is present. For a collapsed pulmonary

Attending to fluid balance and weighing the patient daily should prevent this problem.

VI Surgical Infections

Surgical infections can be defined as infections that require surgical intervention to resolve completely or infections that develop as a complication of surgery. Some are in both categories.

A Overview

Characteristics of surgical infections

They usually involve a penetrating injury (e.g., from trauma), a perforating injury (e.g., a perforated ulcer), or an operative site (e.g., the surgical wound).

Multiple organisms are often present.

Treatment may require surgical drainage of the infection or debridement of necrotic or grossly contaminated tissue; antibiotics alone will not resolve the infection.

Surgical wound infections

The incidence of wound infections is related directly to the nature of the surgical procedure performed. The classification of wounds by extent of contamination is described in Chapter 1, V C.

Clinical presentation. Wound infection often presents as a spiking fever at approximately the fifth to eighth postoperative day. There may be localized wound tenderness, cellulitis, or drainage from the wound.

Treatment. Simple incision and drainage will resolve most postoperative wound infections. Deeper wound infections or extensive necrosis may require operative debridement and antibiotics.

Prosthetic infections. Prostheses are synthetic implantable devices, including vascular grafts, heart valves, artificial joints, fascial mesh replacements, and metallic bone supports.

Clinical presentation. An infected prosthesis usually causes symptoms of either local infection or generalized sepsis. The most common organisms infecting prostheses are staphylococci; these infections are life threatening.

Treatment. Prophylactic antibiotics are always used when implanting a prosthesis; however, an infected prosthesis usually cannot be sterilized with antibiotics and, therefore, removal of the prosthesis is usually necessary.

Prophylactic antibiotics are given during the perioperative period to combat bacterial contamination of tissues that occurs during the operative procedure. The general rules for the use of prophylactic antibiotics are:

The operation must carry a significant risk of a postoperative infection. A clean procedure would not require prophylactic antibiotics, but the following situations would:

A procedure in which a prosthesis is to be implanted

Clean -contaminated procedures, where a nonsterile area is entered; e.g., the respiratory or upper GI tract

Contaminated procedures, such as colon or rectal surgery

The antibiotics used should be effective against the pathogens likely to be present in the operative site.

The antibiotics must reach an effective tissue level at the time of the incision. Therefore, they should be given 1–2 hours before surgery.

The antibiotics should be given for only 6–24 hours after surgery. Longer -lasting regimens offer no additional protection and carry risks of superinfection.

The benefits of the prophylactic antibiotic should outweigh its potential dangers, such as allergic reactions or

the risk of bacterial or fungal superinfections from overgrowth of pathogens.

B Abscesses

Cutaneous abscesses

Types

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Furuncles (boils) are cutaneous staphylococcal abscesses. They are frequently seen with acne and other skin disorders. Bacterial colonization begins in hair follicles and can cause both local cellulitis and abscess formation.

Carbuncles are cutaneous abscesses that spread through the dermis into the subcutaneous region. They are common in individuals with diabetes.

Hidradenitis suppurativa is an infection involving the apocrine sweat glands in the axillary, inguinal, and perineal regions. The infection results in chronic abscess formation and often requires complete excision of the apocrine gland -bearing skin to prevent recurrence.

Causative organisms

Staphylococcal organisms (Staphylococcus epidermidis, Staphylococcus aureus) frequently infect cutaneous lesions. Staphylococci usually produce pus , which must be drained to allow healing.

Other organisms, including anaerobic and gram -negative organisms, can also cause cutaneous abscesses. Coliform organisms are often present in axillary, inguinal, and perineal cutaneous abscesses.

Diagnosis. The microbiologic diagnosis is made by incising the abscess, then culturing and Gram staining the pus. Most staphylococcal organisms are resistant to penicillin; therefore, one of the semisynthetic penicillins, erythromycin, a cephalosporin, or a fluoroquinolone should be used.

Treatment

Drainage

Appropriate antibiotic therapy

Wound care with irrigation and debridement when necessary

Excision of the involved area when it contains multiple small abscesses, sinus tracts, or necrotic tissue.

Intra -abdominal abscesses

Causes

Extrinsic causes include penetrating trauma and surgical procedures.

Intrinsic causes include perforation of a hollow viscus, such as the appendix or duodenum; seeding of bacteria from a source outside the abdomen, e.g., tubo -ovarian abscess; or ischemia and infarction of tissue within the abdomen.

The most common sites are the

Subphrenic space

Subhepatic space

Lateral gutters posteriorly

Pelvis

Periappendiceal or pericolonic areas.

Multiple abscesses are present in up to 15% of cases.

Signs and symptoms of abdominal abscesses are fever, pain, and leukocytosis.

These abscesses may be large and usually produce spiking fevers.

Postoperative abscesses usually produce fever during the second postoperative week.

When there is a delay in seeking medical attention or a delay in diagnosis, patients may present with generalized sepsis.

GI bleeding or pulmonary, renal, or hepatic failure may occur.

Diagnosis. The key to an expeditious diagnosis is a high index of suspicion.

The patient may have tenderness or an abdominal mass, but often no physical findings are present (particularly with a pelvic abscess).

Ultrasonography and CT scan are essential for diagnosis.

Treatment

The mainstay of intra -abdominal abscess treatment is drainage.

Diagnosis and localization with imaging studies allows proper choice of modality.

Unilocular and accessible abscesses can be drained percutaneously with radiologic guidance.

Abscesses that are complex, multilocular, include significant amounts of necrotic debris, or are inaccessible require surgical drainage.

Ideally, drainage is performed without contaminating the general peritoneal cavity.

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Pelvic abscesses may be drained transrectally or through the superior vagina.

Subphrenic abscesses may be drained posteriorly through a twelfth rib approach.

C

Cellulitis is inflammation of the dermal and subcutaneous tissues secondary to nonsuppurative bacterial invasion. It may result from a puncture wound or any other type of skin break.

Signs and symptoms

Cellulitis produces redness, edema, and localized tenderness. Fever and leukocytosis are usually present.

The bacteria may also infect the lymphatics, resulting in red, tender streaks on an extremity (lymphangitis).

A deep abscess can result in overlying cellulitis and should be suspected when a patient does not rapidly respond to antibiotics.

Treatment. The usual organism is a Streptococcus , which is almost always sensitive to penicillin.

D Tetanus prophylaxis

Active immunization with tetanus toxoid injections given in the recommended schedule results in a protective titer within 30 days. This immunization is usually given in infancy (with the diphtheria-pertussis -tetanus shots) or during military induction. A booster dose every 10 years is recommended.

Prophylaxis at the time of injury

Any person with a penetrating injury must receive tetanus prophylaxis if previous immunization cannot be documented.

A previously immunized person should be given a booster dose if not given within the past 5 years.

A patient with a clean injury who has never been immunized may be given the first of three immunizing doses, but the patient must receive the subsequent two doses (4–6 weeks and 6–12 months later, respectively).

A patient with a dirty wound who has never been immunized should be given passive immunization with human tetanus immune globulin intramuscularly.

The protection lasts approximately 1 month.

The first dose of tetanus toxoid may be given at the same time, but it should be given at a separate intramuscular site.

Adequate debridement of devitalized tissue and removal of all foreign debris are also essential.

The value of antibiotics , particularly penicillin, for the prophylaxis of tetanus -prone wounds is unproven. However, for patients who have a suspected Clostridium tetani infection or extensive necrosis, prophylactic penicillin should be given in high doses.

E

Necrotizing fasciitis is a rapidly progressive bacterial infection in which multiple organisms invade fascial planes. The infection travels rapidly and causes vascular thrombosis as it progresses, resulting in necrosis of the tissue involved. The overlying skin may appear normal, leading the clinician to underestimate the severity of the infection. Necrotizing fasciitis may result from a puncture wound, a surgical wound, or open trauma.

Signs and symptoms

Hemorrhagic bullae may develop on the skin, accompanied by edema and redness, and crepitus may be present; however, the skin also may appear normal.

The patient shows signs of progressive toxicity (fever, tachycardia) and may have localized wound pain.

The necrotic wound or tissue involved has a foul -smelling serous discharge.

A plain radiograph of the wound area may reveal air in the soft tissues. CT scans will also show air in the tissues.

Diagnosis. Gram stain reveals multiple organisms, which act synergistically, giving the fasciitis its rapidly progressive and destructive character, including:

Microaerophilic streptococci

Staphylococci

Gram-negative aerobes and anaerobes.

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Treatment is surgical, and early diagnosis is extremely important.

The surgeon attempts to remove all infected or devitalized tissue at the first debridement because remaining necrotic tissue will allow the process to continue.

The removal of large amounts of skin and surrounding tissue and, occasionally, amputation of an extremity may be required.

Daily debridement may be needed.

Appropriate antibiotics in high doses are required.

This infection is life threatening , and prompt treatment is essential.

F

Clostridial myositis and cellulitis (gas gangrene) is most commonly caused by Clostridium perfringens.

Characteristics of wounds susceptible to develop this condition include the following:

Extensive tissue destruction has occurred

Marked impairment of the local blood supply from the injury itself, from complications of the injury (e.g., vascular thrombosis), or from iatrogenic causes (e.g., an overly tight orthopedic cast)

The wound is grossly contaminated

There has been a delay in treatment (usually more than 6 hours)

The patient has a pre-existing condition causing immunologic incompetence, such as corticosteroid drug therapy or poorly controlled diabetes.

Clinical presentation

The onset of symptoms is usually 48 hours after injury but may occur as early as 6 hours after injury.

The most common complaint, severe pain at the site of injury, is due to the rapidly infiltrating infection. This symptom may be obscured if the patient is receiving narcotics. If a surgical patient requires an increase in narcotics, the wound should be examined before the narcotics are increased.

The pulse is rapid and thready. The patient appears diaphoretic, pale, weak, and confused or delirious. The temperature is often, but not always, elevated.

The wound is more tender to the touch than is the usual postoperative wound. The skin may appear normal, but the wound usually drains a brownish serous fluid with a foul odor. Crepitus may appear around the wound edges but is often a late sign.

Blood studies reveal a falling hematocrit and a rising bilirubin from hemolysis. The white blood count may be mildly elevated.

Gram stain of the wound discharge reveals Gram -positive bacilli with spores. Numerous red blood cells are present, but few white cells are present.

A plain x-ray of the wound area may reveal air in the soft tissues.

Treatment. Adequate debridement at the time of initial injury is important for prophylaxis. Treatment for established clostridial infection includes extensive debridement within the tissue planes involved and antibiotics, especially penicillin. If extensive soft tissue necrosis is present in an extremity, amputation may be necessary.

Hyperbaric oxygen therapy is used, but its value is unproven.

Human tetanus immune globulin will not prevent or treat gas gangrene.

Delay in treatment to consider further diagnostic procedures or to observe the patient's course is usually

catastrophic.

G Infections after surgery

Gastrointestinal surgery

Upper GI tract surgery

The rate of serious infections after operations on the upper GI tract is 5%–15%.

The oral cavity is colonized by large numbers of aerobic and anaerobic bacteria. These bacteria are generally killed in the low pH environment of the stomach.

Gastric cultures become positive when obstruction or blood is present; therefore, prophylactic antibiotics should be used in these settings.

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Patients without the protective low gastric pH, e.g., those taking antiulcer medications (H 2 -blockers,

proton pump inhibitors, etc.), achlorhydria, or gastric malignancy also should be given prophylactic antibiotics.

The usual antibiotics are a cephalosporin or a fluoroquinolone to cover both aerobes and anaerobes.

Biliary tract surgery

The biliary tree is not colonized with bacteria in the normal individual. The colonization rate rises to 15%–30% for patients with chronic calculous cholecystitis and to over 80% in patients with common duct obstruction. Of those patients with positive cultures:

Escherichia coli is present in over one half of the cases; other gram -negative organisms account for most of the remainder.

Streptococcus faecalis, the aerobic gram -positive enterococcus, may also be present, and Salmonella strains are occasionally present. Anaerobic organisms, especially C. perfringens , are present in up to 20% of cases.

For elective cholecystectomy, simple prophylaxis with a cephalosporin is adequate.

Therapeutic antibiotics are needed in patients with common duct stones, cholangitis, and empyema or gangrene of the gallbladder. A cephalosporin or penicillin -combination should be given.

Colonic and rectal surgery