Chapter 10: Oncology

Cancer Diagnosis and Registration

Cancer is unregulated cell division with metastatic potential.
In general, there are two broad groups of cancers: solid and haematological malignancies.
Solid malignancies include carcinomas, Melanomas, and sarcomas, which can affect any part of the body. Haematological malignancies include lymphomas, leukemia, and Multiple Myeloma.
The etiology for cancer is multifactorial: environmental and intrinsic.
Risk factors include infections, tobacco smoking, age, chemicals, toxins, genetic predisposition, and radiation exposure.
General cancer prevention strategies need to target risk factors. Cancer screening includes Cervical cancer screening using VIA or pap-smear, Mammography, fecal occult blood with supporting colonoscopy, upper gastro-intestinal endoscopy in high-risk cases for instance those with reflux disease, screening and treatment of premalignant skin lesions in those at risk (e.g. people with Albinism).
Malawi National Cancer Registry pools data from hospital-based cancer registries, KCH, Zomba and Mzuzu Central Hospitals for epidemiology and surveillance. There is also a population-based cancer registry at QECH.

General Clinical Features

SIGNS AND SYMPTOMS

Initial presentation depends on the system involved and may include a mass which may or may not be painful and ulcerated.
GIT tumours may cause difficulties and pain when swallowing, change in bowel habit, abdominal distension.
Genitourinary tumours: abnormal vaginal discharge and bleeding (spotting, heavy, contact), hematuria.
Cutaneous malignancies: pigmented skin lesions, limb edema
Metastatic tumours: back or bone pain, paralysis, fractured limb, headache and seizures.
Cachexia, recurrent fevers, unexplained weight loss and night sweats may occur with advanced disease or leukemia.
Cancers involving skin: ulcer with irregular edges, easily bleeds, necrotic.
For a cancerous mass; it could mobile or fixed, pigmented, exophytic or endophytic with contact bleeding.
Lymphadenopathy
Intraabdominal spread may cause palpable mass, ascites, bowel obstruction, jaundice, nodular/irregular hard prostate on DRE.
Limb involvement causing woody hard edema with or without ulceration, limb swelling due to lymphatic obstruction.

GENERAL INVESTIGATIONS

Laboratory tests:

Full blood count – persistently elevated or decreased parameters in any of the blood cell lines should raise suspicion of a malignancy.
Bcr-Abl detected on PCR if Leukaemia suspected.
Tumour markers -elevated titers of beta-HCG, CEA, AFP, CA-125, PSA, CA 19-9, CA 15-3 and LDH may suggest a particular cancer. Tumour markers may also be used to monitor response to cancer treatment. Caution when interpreting as many are non-specific; need to correlate with the clinical picture and assays used.
Fecal occult blood.

Radiological tests:

Mammography and Ultrasound for breast cancer.
X-rays (Chest/Bone) for detection of primary cancer or metastases.
Scanning (Ultrasound scan/Computed Tomography/Magnetic Resonance Imaging/Bone Scan/PET-CT) investigating particular sites for cancer involvement and the extent.

Haematology, Cytology, Histology:

Peripheral blood smear in haematological cancers
Cytology to assess cancer cells: this examines fluids suspected to be involved with cancer or needle aspirates from cancer masses
Histology for solid tumors: core biopsy, incision, excision, surgical specimen
Bone marrow aspirate and trephine biopsy
Immunohistochemistry: various stains available depending on cancer suspected.

Tests to undertake when specific turmuors are suspected:

Cervical cancer: punch biopsy for histology.
Prostate cancer: Transrectal ultrasound guided prostate biopsy (12 core biopsy is the standard; 6 from each lobe) and PSA. Fusion biopsies are not routinely done in the country at the moment.
HIV test; HIV-related cancers (KS, cervical cancer, lymphoma) are suspected or diagnosed
Barium swallow, gastroscopy and tissue biopsy for oesophagus or gastric cancer
Breast cancer: Breast USS, Mammography, biopsy including immunohistochemistry
Colon cancer: Fecal occult blood, colonoscopy and biopsy
Lung cancer: Sputum cytology, bronchoscopic, mediastinal or CT-guided biopsy
Bladder cancer: Cystoscopy, Urine cytology and Trans-urethral resection of bladder tumour with detrusor muscle biopsy represented in the specimen
Hepatocellular carcinoma: Baseline INR, CT abdomen +/- biopsy, AFP, Hepatitis B and C tests

General Treatment Measures

GENERAL MEASURES

Treatment for cancers involves a multidisciplinary approach with multiple modalities.
These include surgery, radiation, laser therapy, systemic therapies (such as chemotherapy, hormonal therapy, immunotherapy and targeted therapy) and palliative care.
Most of the advanced cancers require all the treatment modalities.
There is evidence to support better outcomes if cancer cases are managed in specialized centres.

Treatment options depend on:

Factors to consider before each treatment

Patient's preference
Availability and cost of treatment as well as expertise on the ground
Co-morbid conditions (hypertension, DM, COPD, cardiovascular, renal and liver conditions)
Performance status (general condition of the patient) assessed using WHO, ECOG, Karnofsky scores.
Age of patient
Organ function (haematological, liver, renal, cardiorespiratory)

Kaposi's Sarcoma