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CAPITULO II VINCULACION ECONOMICA

ADMINISTRACION, CONTROLES Y REGISTROS

• The skin of patients treated with TSEB irradiation at doses of more than 10 Gy

usually develops mild erythema, dry desquamation, and hyperpigmentation.

• At higher doses (greater than 25 Gy), some patients develop transient swelling of the

hands, edema of the ankles, and occasionally large blisters, necessitating local shielding or temporary discontinuation of therapy.

• Unless hair and nails are shielded, loss of these skin appendages occurs by the end

of treatment. They usually regenerate within 4 to 6 months.

• Gynecomastia may also develop; the mechanism for this is unknown.

Long-Term Sequelae

• Chronic cutaneous damage from TSEB irradiation is mild at doses of less than 10 Gy

and acceptably mild through 25 Gy.

• The nature and severity of acute and chronic radiation effects are a function of

technique, fractionation, total dose, concomitant use of topical or systemic cytotoxic drugs, previous treatments, and the condition of the skin before irradiation.

• Superficial atrophy with wrinkling, telangiectasias, xerosis, and uneven pigmentation

are the most common changes.

• Higher doses may produce frank poikiloderma, permanent alopecia, skin fragility, and

References

1. Bigler RD, Crilley P, Micaily B, et al. Autologous bone marrow transplantation for

advanced-stage mycosis fungoides. Bone Marrow Transplant1991;7:133–137.

2. Carney DN, Bunn PA Jr. Manifestations of cutaneous T-cell lymphomas. Dermatol

Surg1980;6:369–377.

3. Honigsmann H, Brenner W, Rauschmeier W, et al. Photochemotherapy for cutaneous T-

cell lymphoma: a follow-up study. J Am Acad Dermatol1984;10:238–245.

4. Hoppe RT, Wood GS, Abel EA. Mycosis fungoides and the Sézary syndrome: pathology,

staging and treatment. Curr Probl Cancer1990;14:293–371.

5. Lamberg SI, Green SB, Byar DP, et al. Clinical staging for cutaneous T-cell lymphoma. Ann

Intern Med1984;100:187–192.

6. Lo TCM, Salzman FA, Moschella ST, et al. Whole body surface electron irradiation in the

treatment of mycosis fungoides: an evaluation of 200 patients. Radiology 1979;130:453–457.

7. Micaily B, Campbell O, Moser C, et al. Total skin electron beam and total nodal irradiation

of cutaneous T-cell lymphoma. Int J Radiat Oncol Biol Phys 1991;20:809–813.

8. Micaily B, Vonderheid EC. Cutaneous T-cell lymphoma. In: Perez CA, Brady LW, eds.

Principles and practice of radiation oncology, 3rd ed. Philadelphia: Lippincott–Raven

Publishers, 1998:763–776.

9. Page V, Gardner A, Karzmark CJ. Patient dosimetry in the electron treatment of large superficial lesions. Radiology1 970;94:635–641.

10. Philips GL, Herzig RH, Lazarus HM, et al. Treatment of resistant malignant lymphoma with cyclophosphamide, total body irradiation, and transplantation of cryopreserved

autologous marrow. N Engl J Med 1984;310:1557–1561.

11. Vonderheid EC, Tan ET, Kantor AF, et al. Long-term efficacy, curative potential, and carcinogenicity of topical mechlorethamine chemotherapy in cutaneous T-cell lymphoma. J

Am Acad Dermatol 1989;20:416–428.

12. Winkler CF, Bunn PA Jr. Cutaneous T-cell lymphoma: a review. Crit Rev Oncol Hematol

15: Brain, Brainstem, and Cerebellum

Anatomy Natural History Clinical Presentation Diagnostic Workup Staging Systems Pathology Prognostic Factors General Management Radiation Therapy

Radiation Therapy Techniques Chemotherapy

Sequelae of Treatment

Management of Individual Tumors

Anaplastic Astrocytoma and Glioblastoma (Malignant Gliomas) Low-Grade Astrocytomas and Oligodendrogliomas

Brainstem Gliomas Ependymoma

Medulloblastoma / Primitive Neuroectodermal Tumor Pineal Region

Primary Central Nervous System Lymphomas Meningioma

Craniopharyngioma

Acoustic Neuroma and Neurofibroma

Hemangioblastoma and Hemangiopericytoma References

Anatomy

• The tentorium, which consists of dense fibrous tissue, separates the supratentorial

and infratentorial compartments (Figs. 15-1 and 15-2).

• In the supratentorial cerebrum, primary motor and sensory areas at the central sulcus

both control the body from the knees to the feet in the medial cortex, and the trunk, arms, and head laterally (homunculus).

• The motor-speech area of Broca is located in the dominant frontal lobe just above the

lateral sulcus; damage causes expressive aphasia. Damage to the dominant temporal lobe at the posterior end of the lateral sulcus results in sensory aphasia (Wernicke's).

• The anterior part of the temporal lobe is partially associated with short-term memory.

• Most of the primary visual cortex is represented on the medial and inferior surface at

the occipital pole.

• The diencephalon consists of the thalamus and the pineal region.

• The mesencephalon rides on the upper part of the clivus at the tentorial notch; its

interior, the tectum, is partially occupied by cranial nerve nuclei (for the oculomotor, trochlear, and proprioceptive portion of trigeminal nerves).

• The dorsal plate houses the superior and inferior colliculi, which regulate eye

movements and hearing impulses, respectively; the trochlear nerve is the only cranial nerve that exits from this dorsal location.

• The pons relays information between the two cerebellar hemispheres, carries the major pathways from the mesencephalon down to the medulla oblongata, and houses the major motor and tactile sensory nuclei for the trigeminal nerve, which emerges from its lateral surface.

• The border between the pons and the medulla oblongata is noteworthy for the

emergence of abducens, facial, and vestibulocochlear (acoustic) cranial nerves.

• The cerebellum develops laterally and posteriorly from the pons region and

differentiates into the median vermis cerebelli and bilateral hemispheres. Anteriorly, the cerebellum faces the dorsal aspects of the pons and the medulla oblongata (in the form of the floor of the fourth ventricle).

• The medulla oblongata forms the link between the pons, spinal cord, and cerebellum;

it houses most of the cranial nerve nuclei (abducens, facial, vestibulocochlear, glossopharyngeal, vagal, accessory, hypoglossal).

• The ventricular system is lined with ependyma and produces cerebrospinal fluid

(CSF) in the roofs of the fourth and third ventricles, the medial walls of the central body, and the inferior horns of the lateral ventricles.

• The foramina of Monro transmit CSF between the third and lateral ventricles at the

superolateral corners of the third ventricle.

• The aqueduct of Sylvius in the midbrain is the narrowest canal of the intracranial

nervous system and is also the most common location of obstruction of flow by compression, which causes noncommunicating hydrocephalus.

• CSF escapes the ventricular system through the median foramen of Magendie and

the two lateral foramina of Luschka to the subarachnoid space, which are located in the roof and lateral corners of the fourth ventricle at the level of the medulla

oblongata.

• The subarachnoid space widens into several cisterns; the largest are the cisterna

magna (posterior to medulla oblongata just at foramen magnum), the cistern of the lateral sulcus bilaterally at the base of the brain, and the ambient cistern posterior to the midbrain.

Fig. 15-1: Frontal section through telencephalon at the plane of the anterior commissure. (From Sobotta. Atlas der anatomie des menschen, 20th ed. Munich: Urban &

Fig. 15-2: Supratentorial parts of central nervous system (CNS) include telencephalon (cerebral hemispheres with frontal, parietal, occipital, and temporal lobes) and

diencephalon, with dominant thalamic nucleus, hypothalamus, pituitary stalk, and

neurohypophysis inferoanteriorly and pineal body posteriorly, which represent the midline central structures of the supratentorial CNS. (From Sobotta. Atlas der anatomie des

menschen, 20th ed. Munich: Urban & Schwarzenberg, 1993, with permission.)

Natural History

• Primary brain neoplasms usually spread invasively without forming a natural capsule.

• Presenting symptoms depend on tumor expansion and surrounding edema.

• Intracranial primary neoplasms do not metastasize through the lymphatics.

• Extracranial true metastases from primary brain tumors are rare, but sometimes can

occur with high-grade medulloblastoma, dysgerminoma, hemangiopericytoma, sarcoma, and high-grade astrocytoma. These hematogenous metastases often appear in the lung; medulloblastoma has an affinity for bone and lymph nodes.

• Peritoneal metastases occasionally occur in patients receiving ventriculoperitoneal

shunt to relieve obstructive hydrocephalus from tumors.

• Some high-grade neoplasms in the brain and meninges metastasize by "seeding" into the subarachnoid and ventricular spaces and in the spinal canal, particularly in patients with recurrent tumors. Tumors with a propensity for CSF spread include medulloblastoma, ependymoblastoma, pineoblastoma, and central nervous system (CNS) lymphomas.