Carlo Palmieri and Anjana Singh discuss the surgical option available in managing malignant disease
Malignant disease can be managed surgically, medically or both. Medical treatments include chemotherapy, radiotherapy, endocrine therapy, immunotherapy, and monoclonal antibodies.
Our next article will deal with the medical aspects. Here we talk about the surgical options.
Surgery plays a central role in managing malignant tumours and surgeons are often the first to see patients with symptoms and signs suggestive of malignancy. Surgical oncology has a broad remit and includes the following.
Prophylaxis
Surgery can be used to prevent cancer in patients with an inherited predisposition to certain malignancies. Examples include:
- Proctocolectomy to prevent colorectal cancer in people with familial adenomatous polyposis coli.
- Women with known genetic mutations predisposing to breast cancer--for example, BRCA1/2 mutations can benefit from prophylactic mastectomy.
Screening
This involves looking for early signs of cancer in high risk population groups and currently there are two well established screening programmes in Britain for breast and cervical cancer. In addition surgeons run clinics for those at high risk of breast cancer.
Family history and high risk clinic
Women with a strong family history of breast cancer or with known predisposing genetic mutations are regularly reviewed in these clinics.
Diagnosis
Surgeons are involved in making the initial clinical diagnosis through the process of history, examination, and special investigations, which includes tissue biopsies that can provide the essential pathological diagnosis.1
Staging
This involves investigations that include blood tests, chest radiograph, liver ultrasound, and bone scan to look for any evidence of distant metastases. This is clinical staging and these tests are usually arranged in the clinic after diagnosis.
Further staging information is provided from the operation when the primary tumour and the regional lymph nodes are removed and given to the pathologist for histological examination. This is pathological staging. Pathological staging provides important prognostic information. Examples include the TNM classification and Dukes's classification.
TNM classification system
Most staging systems are based on an assessment of the size of the tumour (T), the presence of lymph node metastases (N), and the existence of distant metastases (M).
T and N are accurately assessed by pathological staging and M is assessed
by clinical staging. TNM classification provides information about prognosis and guides further treatment decisions.
For example, in breast cancer the presence of axillary lymph node metastases is the biggest risk factor for predicting relapse and death. This directly influences decisions regarding administration of chemotherapy.
Dukes's classification
In colon cancer, the classical Dukes's classification is still referred to and has prognostic importance.
- Dukes's A: invasion of cancer into the bowel wall (no spread beyond muscle layer).
- Dukes's B: invasion through the bowel wall.
- Dukes's C: involvement of local lymph nodes.
- In practice, a modified Dukes's classification is used, which includes Duke's D--that is, presence of distant metastases and is more like the TNM classification.
Treatment
Curative
Surgery is a curative treatment for solid tumours if carried out before metastasis has occurred. Treatment ranges from a wide local excision of the cancer to the removal of the whole organ. Examples include nephrectomy for renal cell cancer and wide local excision or mastectomy for breast cancer.
Surgery can be used to treat in the metastatic setting to remove localised metastasis, which may result in cure. Examples include solitary hepatic metastasis in colorectal cancer and retroperitoneal lymph node dissection in testicular cancer.
Adjuvant therapy
Surgery has been used in the past in adjuvant setting for tumours known to be dependent on hormones for growth--that is, breast and prostate cancer. In addition, surgery has a supportive role in the delivery of adjuvant chemotherapy. Examples include oophorectomy in breast cancer or orchidectomy in prostatic cancer (now generally superseded by the development of LHRH analogues) and insertion of Hickman lines for administration of adjuvant chemotherapy.
Palliative
In this context, surgery may be used to debulk the tumour and so improve response to subsequent chemotherapy, to provide symptomatic relief, or to prevent complications due to metastatic disease. It can:
- Improve response to subsequent treatment--for example, debulking of advanced ovarian cancer.
- Relieve gastrointestinal obstruction--for example, resection of advanced gastric or colonic carcinoma or a surgical bypass procedure to relieve obstruction.
- Prevent or deal with complication due to metastatic disease--for example, orthopaedic intervention to prevent fractures or treat fracture secondary to bone metastases.
- Relieve symptoms--for example, insertion of shunts: Denver shunt for ascites and oesophageal stent to relieve dysphagia in oesophageal cancer.
Plastic and reconstructive surgery
This is used to modify and reduce the functional, cosmetic, and psychological morbidity that can occur after radical surgery to remove a tumour. Examples include breast reconstruction after mastectomy and reconstructive surgery of face after excision of oral tumours, skin cancers, and head and neck tumours.
