Oncology of the nervous system

As with other high-incidence cancers, the EOC model of care in the care of the patient with cancer of the nervous system is the Specialty Oncology Centers (COS), the most modern and effective response to cancer disease.

The Oncology Center

Centers of expertise structured by organ, EOCs organize and optimize the care of the patient with cancer disease in a multidisciplinary and interprofessional care network. The model involves the cross-disciplinary and coordinated involvement of professionals with complementary specialties, the centralization of highly specialized services, and an accompanying service to treatment and recovery in all EOC hospitals.

Thanks to this model of care, EOC offers all Ticino patients up-to-date treatment protocols on the highest international standards and access to the best diagnostic, therapeutic and care pathway.

Tumors affecting the nervous system are manifold and can be either primary (i.e., originating from tissues proper to the nervous system, such as the meninges, glial cells, and ependyma) or secondary, i.e., localizations of tumors from other body districts (such as tumors of the lymphatic system, metastases of solid tumors, or others). Secondary tumors are more frequent, primary tumors relatively less frequent, among the latter most often found are meningiomas and gliomas.

• Meningiomas: account for 30 percent of primary tumors. These tumors originate from the cells that make up the lining sheets of the brain and spinal cord and are in most (>85% of cases) slow-growing benign tumors.
• Gliomas (astrocytomas, oligodendrogliomas, glioblastomas): these tumors collectively account for 33% of primary tumors. They originate from glial cells, which serve as the support of neurons, and are characterized by varying degrees of aggressiveness. They can be studied on the basis of their radiological, histological, and biomolecular features.
• Neurinomas (or schwannomas): these tumors originate from the lining cells of nerve roots and peripheral nerves and are in most cases mildly aggressive tumors.
• Medulloblastoma: this is the most frequent type of malignant brain tumor in pediatric age. It is localized in the cerebellum. Its aggressive characteristics vary according to its genetic and biomolecular profile.
• Pituitary adenoma: accounts for about 10% of intracranial tumors. It is a tumor of the pituitary gland, which may or may not have hormonal activity.
• Rarer tumors include ependymomas, hemangiopericytomas, chordomas, pineal tumors, and germinomas.

Complex, multidisciplinary care

The nervous system consists mainly of neurons (the so-called gray substance) and glial cells (the so-called white substance), along with all ancillary tissues such as blood vessels, meninges (lining the brain and spinal cord), and ependyma (lining the cavities containing the cephalochid fluid).

Cancers affecting the nervous system are clinical realities that require complex, multidisciplinary care because of the multiple manifestations ofthe disease and the impact of the disease itself and cancer therapies. For these same reasons, it has become necessary to develop medical, surgical, and radiation treatments that combine appropriate precision and intensity, with the most accurate sparing of healthy tissue, in order to improve cure rates and survival while ensuring the best quality of life and functional sparing.

Diagnosis

Diagnostics in brain tumors are aimed at multiple purposes:

• To ascertain the oncologic nature of the lesion(s) found in the brain, and at the same time to rule out other causes requiring different treatments.
• To characterize the biological behavior of the tumor, i.e., its degree of aggressiveness, for the selection of the best treatment.
• Determine the precise anatomical location of the lesions, in order to guide surgical and/or radiotherapy treatment to the maximum possible sparing of the areas of the brain responsible for basic functions (movement, speech, vision, etc.).
• Check the effects of different therapies and the identification of any adverse events or complications.

The main examination that is used is multiparametric MRI: using magnetic fields, radiofrequencies, and contrast agent, MRI allows detailed images of the structures of the nervous system to be obtained, which provide many different pieces of information on both the morphology and biological characteristics of brain and spinal tumors. It is used both in the diagnostic phase and in the phase of verifying the effects of treatments, and for these reasons it plays a crucial role throughout the patient care pathway.

The multiple "parameters" correspond to the different types of information, which MRI is able to extract noninvasively through imaging: for example, the density of cells or the amount of blood supplying a tumor may reflect, in certain cases, the degree of aggressiveness of the disease.

Other important tests in diagnosing tumors of the nervous system, provided by the nuclear medicine service, are:

• PET/CT with Fluoroethyltyrosine (FET): useful particularly in gliomas, for metabolic evaluation at diagnosis or for differential diagnosis between disease recurrence and post-treatment changes.
• PET/CT with 68Ga-DOTATATE: particularly useful for evaluation of the extent of complex meningiomas.

In the suspicion of a brain tumor, radiological examinations are essential, but certainty of diagnosis is obtained only by histologic examination, performed in the laboratory by the pathologist, by sampling of tumor cells or tissue by examination of cerebrospinal fluid or biopsy performed by the neurosurgeon.

In order to be evaluated under the microscope, the biopsy is subjected to histochemical staining and immunohistochemical analysis: through analysis of morphology and other features of tumor cells, the type and grade of brain tumor can be classified.
It is also to date necessary to perform an additional level of investigation. Indeed, alterations in the genes and molecules that make up and define the tumor make it possible to identify targets to be hit by radiation and chemotherapy treatments. A recent development in molecular diagnosis concerns the assessment of tumor methylation status (methyloma), which is characteristic for different histotypes. This evaluation allows for confirmation and clarification of the histopathological diagnosis, especially in doubtful cases.

Treatments

The brain tumor represents a lesion that occupies space within the head box; therefore, all types of treatment aim to reduce or remove, if possible completely, the tumor mass. Surgery, radiation therapy, and medical oncology therapy, often in combination, seek to achieve this goal.

• Neurosurgery is the surgical discipline that seeks to maximize resection while minimizing risk to the patient.
  Based on the amount of tumor that can be removed, we speak of:
  • Complete surgical resection.
  • Partial surgical resection or debulking.
  • Biopsy: if only a few fragments are taken.
• Radio-oncology: radiotherapy, variously combined with surgery, chemotherapy or the use of molecularly targeted drugs or immunotherapeutics, contributes to the treatment process and to the maintenance of the patient's neurological function and autonomy. Radiation therapy involves the use of high-energy ionizing radiation for therapeutic purposes, delivering the most intense and effective dose possible to the tumor tissue, while trying to spare surrounding healthy tissues and organs as best as possible. It is an outpatient treatment and does not involve invasive procedures. It can have several purposes:
  • Curative intent: it is performed for the purpose of radically eliminating all tumor cells in the nervous system tissue, such as encephalon or spinal cord.
  • Postoperative (adjuvant) intent: is performed within a few weeks after surgery to eliminate any remaining tumor cells and reduce the risk of local recurrence.
  • Palliative intent: is performed in patients in whom the disease is symptomatic and as an alternative to other treatments.
  • Stereotactic radiotherapy and radiosurgery: this is a high-dose form of radiotherapy, usually delivered to small volumes to be ablatively treated, such as skull base tumors and metastases, in a limited number of sessions, usually 1 to 5. Stereotactic radiotherapy has many important applications in the treatment of tumors of the nervous system because it allows dose limitation to healthy organs even when they are particularly close to the tumor target.
• Medical oncology: deals with providing drug therapy based on the individual patient, the type of brain tumor, and its histological and molecular biology characteristics. In addition to this, medical neuro-oncology is concerned with the implementation of supportive measures, coordination of treatment, and care after therapy. Cancer drugs in tumors of the nervous system are used in different situations:
  • Curative therapy: after an operation, drug therapy alone or combined with radiation therapy is often considered.
  • Adjuvant therapy: these are the therapies undertaken after an operation with the aim of destroying residual tumor cells. This reduces the risk of recurrence or delays disease progression.
  • Palliative therapy: when cure is unlikely, the goal is to keep the disease and its disorders under control.
  • Experimental therapy: drug treatments are received in the context of clinical trials aimed at understanding the effectiveness of new treatments not yet approved or marketed for the treatment of brain tumors.

Neurosurgical intervention and technology

Today advanced technological tools assist the surgeon in neurosurgical intervention.
Neurosurgical intervention takes place in the operating room, in a sterile manner, usually by minimal trichotomy (shaving) of the area necessary for skin incision. By means of a craniotomy, the inside of the cranial box and the brain compartment where the tumor is located are accessed, incising, if necessary, the meninges lining the brain.
The use of technological tools during surgery allows the surgeon to remove as much of the tumor as possible while preserving neurological function as much as possible:

• The microscope: allows magnified visualization of the surgical field, better distinguishing diseased tissue from healthy tissue.
• Neuronavigation: like a GPS, it allows preoperative CT or MRI scans to be "navigated," indicating precisely where the tumor is located.
• Intraoperative fluorescence: is the ability to microscopically visualize tumor cells that become "fluorescent."
• Intraoperative ultrasound: ensures a real-time "image" of different tissues, healthy and diseased, reducing the risk of residual.
• Neurophysiological monitoring: is the intraoperative assessment of motor and sensory functions by continuous intraoperative electrical stimulation.

Epileptic seizures: diagnosis and treatment

One symptom resulting from the presence of a brain tumor may be the manifestation of seizures. These are motor phenomena (involuntary rhythmic muscle movements) or dispersive (deja-vu, colored visions, intense tingling) to loss of consciousness and seizures, resulting from aberrant electrical signals that develop in this case due to tumor interference in brain function.
Brain tumor-related epilepsy benefits from treatment of the underlying pathology and treatment in combination with specific drugs (called antiepileptics or anti-convulsants) that control the genesis of these dysfunctional electrical signals.

Diagnosis of epilepsy uses the performance of electroencephalogram or EEG, which noninvasively records electrical activity in the brain by attaching a headset with electrodes to the head.

Managing the return home

Returning home after neurosurgical surgery is a very delicate time for the patient and his or her family.The patient is followed through all stages of the care journey, including providing information and advice to be taken during the postoperative phase.

Quality and safety of care

Multidisciplinary meetings, adherence to guidelines, and internal and external quality audits ensure the quality and safety of the care provided.
The team at the Swiss Italian Neuro-Oncology Center includes many specialists (neuro-radiologist, neurologist, neurosurgeon, radiation oncologist, medical oncologist, clinical nurse specialist and clinical expert, anatomo-pathologist, palliative care physician, rehabilitation physician, psycho-oncologist), who take care of the patient in a coordinated and shared manner.

Multidisciplinary meetings
Multidisciplinary meetings or multi-disciplinary meetings (MDMs) are a tool to further ensure the quality and safety of care provided.
Multidisciplinary meetings aim to ensure that patients have access to the discussion of their case with the involvement of multiple specialists in order to develop the best and expert decision regarding the management of the diagnostic pathway and treatment choices.
Beginning with the multidisciplinary discussion and in particular with the contribution of the clinical expert, the patient is directed and accompanied in his or her journey along the relevant diagnostic-therapeutic stages in the different institutes that make up the CNSI.

Quality standards
The Center undergoes periodic internal and external quality audits according to requirements established by guidelines issued for international certification.

Cancer League Ticino

In the field of oncology of the nervous system, the collaboration with the Cancer League of Ticino provides patients with specialized counseling in social and intensive oncological rehabilitation, offering patients and family members advice and support in administrative, financial and other areas.

Through its regional offices (Bellinzona, Locarno, Lugano, Mendrisio), the League is available to all patients and family members for counseling in the social, psychological and rehabilitation fields.

More information is available on the website or by calling 091 820 64 20. Also available is the Cancer Info hotline on 0800 11 88 11 where a nurse with a specialization in the oncology area answers questions from patients and family members in the three national languages.

The League also supports cancer research, offers prevention information campaigns and cooperates with self-help associations.

Clinical manager

Doctors on the surgical core team