Multidisciplinary, Interdisciplinary Approach to Management of Cancer

"The 1st decision is the most important determination of success in cancer treatment and this should be a multi-modal effort."

For many years, the traditional approach to the treatment of cancer patients has been almost exclusively oriented towards specialized decision–making. Consequently, certain neoplasms in both adults and children have been characterized as either “surgical” or “radiotherapeutic” diseases. More recently, the medical oncologist has been involved in the primary and almost exclusive responsibility for particular neoplastic diseases and all disseminated solid tumors. The empirical connection of diseases with particular clinical specialties or disciplines has caused numerous obstacles to progress in the treatment of cancer in general.

Today, modern treatment has shifted from specialization to integration for every single cancer. A given neoplasm is no longer considered to be within the exclusive domain or under the initial control of a certain clinical discipline, but rather cancer treatment must be conceived and carried out strategically using the therapeutic potential of several modalities in the attempt to destroy all the sites of disease (combined modality treatment or MULTIDISPLINARY APPROACH to the management of cancer).

The management of cancer must be multi-disciplinary interdisciplinary, with each discipline respecting the specialty expertise of the other, all for the benefit of the cancer patient, with consideration of the current state of the art of cancer management.

The essential elements for combined modality treatment are:

1. Knowledge of the natural history
   • Neoplasm or stage or subgroup at high risk of early dissemination especially hematogenous spread
   • Histologic type at high risk of relapse
   • New diagnostic methods for better determination of the anatomical extent
   • Neoplasm responsive to radio- and /or chemotherapy
2. Knowledge about the efficacy of various modalities
   • Efficacy/ Limitations of radical surgery
   • Efficacy/ Limitations of radical radiotherapy
   • Efficacy/ Limitations of extensive or adjuvant irradiation in some neoplasms
   • Efficacy/ Limitation of chemotherapy or hormonal therapy
   • Neoplasm in which one or more drugs have recently been shown to be effective
3. Local facilities
   • Uniformity of clinical, oncologic approach
   • Presence, in the same center, of experts in the various diagnostic and therapeutic branches (pathology, radiobiology, endoscopy, surgery, medical oncology, pain and rehabilitation therapy).
   • Adequate number of doctors, nurses and secretaries
   • High-energy radiotherapy
   • Outpatient clinic and day hospital
   • New anti-neoplastic drugs
   • Adequate supportive therapy

THERAPEUTIC MODALITIES AGAINST CANCER

The finality of treatment of a cancer patient demands that therapy be undertaken only by those who are capable and properly trained. There are few situations in medicine where the stakes are high and the therapeutic procedures as decisive for cure or death. The responsibility is great and the judgement is critical. This is reflected in the emergence of specialties in virtually all major discipline – i.e. radiation oncology, medical oncology, surgical oncology, gynecologic oncology, and pediatric oncology. The first decision is the most important determination of success in treatment and this should be a multi-modal effort.

"The second most important principle in therapy is to cure or to control the disease or to palliate the symptoms of the patient with minimal functional and structural impairment."

The decision as to how radical treatment should be, is determined by:

• the aggressiveness of cancer, the predictability in regard to its spread,
• the morbidity and mortality of the therapeutic procedure,
• and the cure rate for the therapeutic procedure under consideration.

The treatment of patients with malignant disorders is characterized by the following reasoning:

• What is the goal of the treatment?
• Do benefits outweigh risks in achieving these goals?
• Is difference between potential benefit and harm worth the cost?

There are therefore, two major modalities of cancer treatment:

LOCOREGIONAL TREATMENT MODALITY

1. Surgery
2. Radiotherapy – teletherapy (cobalt, linear accelerator, IMRT, IGRT, tomotherapy) or brachytherapy

SYSTEMIC TREATMENT MODALITY

1. Cytotoxic chemotherapy
2. Hormonal therapy
3. Immunologic therapy
4. Gene therapy

SURGICAL ONCOLOGY
To cure…To control…To palliate

When treating a patient with newly diagnosed cancer, the surgeon (surgical oncologist, colorectal surgeon, gynecology-oncologist, urologist, thoraco-vascular surgeon, neurosurgeon, orthopaedic oncologist, otolaryngo-oncologist) has several responsibilities within the context of multidisciplinary-interdisciplinary approach to cancer patient care (see links to different societies and members):

1. Biopsy for tissue diagnosis
2. Surgical resection of the tumor when appropriate with attention given to the needs of other consultants such as marking residual tumor for irradiation, or removing lymph nodes for staging purposes, or getting fresh specimen for tumor marker assay, and
3. Adequate staging
4. Consultation with medical, pediatric and radiation oncologists as to the indications for adjuvant therapy
5. Surgical resection for cure, control or palliation , and
6. Appropriate follow-up of patient with inter-disciplinary modality approach.

Surgery is the main treatment modality of early stage solid tumors and usually with an aim for cure. Surgery can be done in all tertiary hospitals and medical centers in the Philippines.

RADIO-ONCOLOGY
To control…To palliate

Radiation therapy involves radiation inactivation of cancer cells. The ideal in radiation therapy of malignant disease is achieved when the tumor is completely eradicated and the surrounding normal tissues show minimal evidence of structural and functional injury.

Radiotherapy can be given as an external beam (teletherapy) or close to or within the tumor (brachytherapy).

Radiotherapy is the responsibility of the Radio-Oncologist, working in the context of multidisciplinary interdisciplinary approach to cancer management. There are a limited hospital centers with radiation facilities – see website for directory.

MEDICAL / PEDIATRIC ONCOLOGY
To cure… To control… To palliate

Chemotherapy refers to the use of drugs in the treatment of any disease. Chemotherapy has been indelibly linked to cancer because of the reputation of anti-cancer drugs and their effects on the patient. In truth, chemotherapy involves the use of not only cytotoxic agents, but of other agents such as hormones, anti-hormones, and cellular products. All have a systemic effect on the patient.

Chemotherapy must be in the hands of the Medical Oncologist (for adult patients) or of the Pediatric Oncologist (for children) – in their absence under the Internist or the Pediatrician, working in the context of multidisciplinary interdisciplinary approach to cancer management. There are now evolving sub-sub-specialty IM oncologist – like neuro-oncology.

The types of systemic therapy include the following:

• CYTOTOXIC chemotherapy – the drugs usually attack rapidly dividing cells.
• HORMONAL therapy – can be hormones or anti-hormones, used against hormone-sensitive tumors.
• IMMUNOLOGIC therapy – the use of biologic response modifiers, natural cellular products, as main modality or adjunct therapy against cancer.

Chemotherapy for cancer treatment is classified according to its goal in combination with other modalities of treatment:

• PRIMARY chemotherapy – Chemotherapy is the main modality of treatment. Usually, these is in the setting of aggressive tumors with high probability of systemic involvement (e.g., lymphoma, leukemia, small cell lung cancer).
• ADJUVANT chemotherapy – Chemotherapy given after a loco-regional therapy (surgery or radiotherapy) with the aim of controlling micro-metastatic disease, prolonging disease-free and overall survival (e.g., breast, colon, rectum, ovary, osteosarcoma cancers).
• NEO-ADJUVANT chemotherapy – Chemotherapy given before a definitive loco-regional therapy (surgery or radiotherapy) with the purpose of decreasing tumor size or better loco-regional control later, as well as controlling micro-metastasis and prolonging disease-free and overall survival (e.g., breast, non-small cell lung, head & neck cancers).
• CONCURRENT chemotherapy – The simultaneous use of chemotherapy and radiotherapy in the management of cancer (e.g., head & neck, lung cancers).

Many tertiary hospitals and medical centers in the Philippines are with Medical Oncologists – see website for directory.

OTHER DISCIPLINES involved in the multidisciplinary care of the cancer patient are:

• Pathology specialists
• Pain specialists
• Psychosocial counsellors
• Rehabilitation specialists
• Oncology nurses
• Nutritional counsellors
• Spiritual counsellors