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Retinoblastoma
- 1. Retinoblastoma Dra. Ana Paula Castillo González Residente de segundo año Hospital Regional de Alta Especialidad de la Península de Yucatán DIAGNÓSTICO POR IMAGENOLOGÍA.
- 2. INTRODUCCIÓN • Tumor maligno intraocular mas común en la infancia. • Tumor primario de la retina de alta malignidad que se origina de las células neuroectodérmicas (capa de la retina destinadas a convertirse en fotorreceptores). • Mutación en la proteína Rb, codificada por un gen supresor tumoral denominado RB1en el cromosoma 13q14. Hereditarios, 40% - bilateral. Esporádicos, 60% - unilaterales.
- 3. EPIDEMIOLOGÍA • Sin predisposición racial o sexual. • Edad: menores de 5 años. • En el mundo: 1 caso cada 18,000 a 30,000 nacidos vivos. • Mortalidad debida a invasión tumoral y metástasis. • Diagnóstico precoz: tasa de supervivencia a los 5 años en tumores limitados al globo es superior al 90%.
- 4. MACROSCÓPICO
- 5. MICROSCÓPICO • NECROSIS Y FOCOS DE CALCIFICACION • INDIFERENCIADO O BIEN DIFERENCIADO PEQUEÑAS CELULAS REDONDA U OVOIDES CON ESCASO CITOPLASMA Y NÚCLEOS GRANDES.
- 6. DIAGNÓSTICO • LEUCOCORIA • ESTRABISMO • OPACIDAD CORNEAL • HETEROCORMIA DEL IRIS • PROCESO INFLAMATORIO • HIFEMA • GLAUCOMA • OJO ROJO • DOLOR OCULAR • BLEFAROPTOSIS
- 7. SistemadeClasificación InternacionaldelRetinoblastomaIntraocular(CIRI) Grupo A. Tumores confinados a la retina. Ningún tumor a < 3mm de la fóvea o < 1.5mm del nervio óptico. Sin siembras vítreas. Grupo B. Tumores confinados a la retina, macular o yuxtapapilar, sin siembras vítreas. Sin desprendimiento de retina >5mm de la base del tumor. Grupo C. Siembra vítrea o en espacio subretiniano, finas a < 3mm del tumor (localizadas). Grupo D. Siembra tumoral difusa. Bolas de nieve o masas avasculares en vítreo o Rb exofítico.
- 8. EXTENSO GRUPO E Sin potencial visual, o presencia de una o más de las siguientes características: • Tumor en el segmento anterior. • Tumor anterior a la cara anterior del vítreo. • Glaucoma neovascular. • Hemorragia vítrea que oscurece el tumor o hifema significativo, contacto con el lente. • Presentación semejante a celulitis orbitaria. EXTRAESCLERAL GRUPO F Invasión extraescleral hacia el nervio óptico, órbita, o cerebro; metástasis a distancia. SistemadeClasificación InternacionaldelRetinoblastomaIntraocular(CIRI)
- 10. QUIMIO REDUCCION ( CEV) GRUPO A QUIMIOTERAPIA SISTÉMICA, CON BUENA VISIÓN GRUPOS BCD BILATERAL: ESPERAR RESPUESTA DE QUIMIO, E INTENTAR SALVAMIENTO DEL OJO CON MEJOR RESPUESTA TRATAMIENTO
- 16. RB INTRAOCULAR ENDOFÍTICO EXOFÍTICO DIFUSO RB EXTRAOCULAR ENFERMEDAD EN EL SISTEMA NERVIOSO CENTRAL TRILATERAL TETRALATERAL LEPTOMENÍNGEA
- 17. INTRAOCULAR • Se proyecta hacia adelante, atraviesa la membrana limitante interna de la retina y crece hacia el vítreo. • Grupos A, B, C o D. SIEMBRA TUMORAL ENDOFÍTICO
- 19. Retina Espacio subretiniano Elevación de la retina DESPRENDIMIENTO DE RETINA INTRAOCULAR EXOFÍTICO • Grupo D, E (Esclera).
- 21. DIFUSO • MASA PLACOIDE • SIN CALCIFICACIONES • SIMULA ENFERMEDADES INFLAMATORIAS O HEMORRÁGICAS. INTRAOCULAR
- 22. EXTRAOCULAR • Mal pronóstico. • Esclera: Grupo E, Retinoblastoma extenso. • Extraescleral: Grupo F. • Incidencia baja. • Supervivencia a 3 años, 58% - 77% • Tumor en grasa orbitaria (fat sat). INFILTRACIÓN EXRAESCLERAL
- 23. INFILTRACIÓN ESCLERAL Y EXRAESCLERAL
- 24. EXTRAOCULAR • Volumen del tumor: > 1.30 cm3 (70%), < 1,3 cc (36%). • Engrosamiento del complejo retinocoroideo. INVOLUCRO AL NERVIO ÓPTICO Mortalidad 13% a 89% involucro del Nervio Óptico postlaminar. Indica enucleación y quimioterapia adyuvante. Invasión prelaminar:
- 26. • ES EL SINDROME QUE ASOCIA UN RETINOBLASTOMA BILATERAL CON UN TUMOR INTRACRANEAL SOLITARIO DE LA LINEA MEDIA EN A GLANDULA PINEAL, LA REGION SUPRASELAR O LA REGION PARASELAR- • Retinoblastoma ectópico en la glándula pineal o región paraselar. • Pinealoblastoma. • Origen neuro- ectodérmico común. TRILATERAL EnfermedadenelSNC
- 27. TRILATERAL
- 28. TRILATERAL
- 30. • DOS TUMORES NEUROBLÁSTICOS INTRACRANEALES DISTINTOS EN LA LÍNEA MEDIA ASOCIADOS A RB BILATERAL. TETRALATERAL Enfermedad en el SNC
- 31. TETRALATERAL
- 32. Conclusión El papel del radiólogo en el diagnóstico del retinoblastoma es importante ya que es uno de los pocos tumores malignos en los que se realiza el tratamiento sin confirmación histopatológica del diagnóstico, así mismo es importante para la estadificación del tumor; pequeños cambios en la morfología y distribución del tumor cambia radicalmente el tratamiento y el pronóstico del paciente.
- 33. • RADIOPAEDIA
Notas del editor
- Si hay una deleción cromosómica suficientemente grande puede producir manifestaciones dismórficas sistémicas como microcefalia, malformaciones genitales, anomalías auriculares, retraso mental y anomalías dactilares. Los pacientes con ca hereditario tienen gran susceptibilidad para desarrollar otros canceres extraoculares, como sarcoma osteogénico, así como otras neoplasias en el sitio de irradiación.
- Es una masa blanca amarilla que puede presentar zonas de necrosis y calcificaciones. Produce leucocoria, que es un signo ocasionado por cualquier anomalía intraocular de color blanco, que refleja la luz que incide a través de la pupila. Muy importante diagnosticar el Retinoblastoma porque es uno de los pocos cánceres humanos en los que se realiza el tratamiento sin confirmación histopatológica del diagnóstico. Realizar exploración de fondo de ojo a todos los niños menores de 5 años. Las pequeñas se ven como focos intrarretinianos blanco-gris, debido a la diferencia de color de la retina y coroides, pueden verse incluso cuando miden < 0.02mm.
- Puede presentar signos de diferenciación en fotorreceptores en forma de rosetas de flexner- wintersteiner y fleurettes El tumor esta compuesto de con variablilidad histologica: necrosis y focos de calcificacion.
- CENETEC: TODOS LOS NIÑOS CON ESTRABISMO O SOSPECHA DE ESTRABISMO DEBERA SER VALORADOS EN BUSCA DE REFLEJO ROJO
- Sistema de Clasificación Internacional del Retinoblastoma Intraocular (CIRI). Esta clasificación está incluída en las guías de práctica clínica.
- CEV: CARBOPLATINO, VINCRISTINA Y ETOPOSIDO. TRATAMIENTO SEGÚN GUIAS CENETEC.
- Ultrasonido en escala de grises muy útil para valorar la forma, tamaño, calcificaciones, y siembra tumoral en vítreo.
- Anatomia normal del ojo, esquema y rm. Esclera Uvea: coroides, cuerpo ciliar e iris. Retina: ora serrata es la porción nmas anterior de la retina, la zona de transición serrada está entre el margen anterior de la retina y los cuerpos ciliares. Desprendimiento d retina: forma en reloj de arena
- RM Metodo de elección para estadificar --- tratamiento T1: señal de intensidad intermedia, hiperintensa en comparación con el vítreo y LCR. T2: hipointenso ( vítero y LCR) T1 C+ (Gd) pequeños: realce homogéneo los grandes con zonas de necrosis y calcificaciones: heterogéneo. Si coroides tiene un realce adyacente a los márgenes del tumor, cosniderar un involucro coroidal; sin embargo una reacción inflamatoria se ve igual. Realce de la cámara anterior no significa involucro tumoral, ( hyperemia, neovascularizacion) Muy importante fijarnos en el nervio optico y el disco. Para saber si hay involucro de la esclera ( hipointensa), presenta realce por tumoracion. DWI hay restriccion. ADC: nos permite valorar el tejido necrotico viable y no viable.
- eco gradiente, t1 + c,
- El retinoblastoma puede presentarse como: A. Una masa retiiana o subretiniana B. Un desprendimiento de retina de etiologia poco clara Un vitreo opaco, con mala visualizacion de las estructuras retinianas y pocos indicios sobre la causa de alteraciones vitreas
- Endofítico: crece hacia el vítreo. Asociado a siembra tumoral, estas pueden estar en vítreo o en espacio subretiniano. La siembra tumoral indica un grupo C si están a menos de 3mm del tumor, grupo D si están difusas. Cuando están en el vítreo es mas sensible de observarlas con oftalmoscopio. Estas cambian el tratamiento del Rb. No responden solo a la quimioterapia, se les complementa con radiación o enucleación. LAS SECUENCIAS INDICADAS PARA SIEMBRA TUMORAL SON T2 Y FAST SPIN ECHO Si no se ven en rm no significa que no tenga, son mas evidentes en oftalmoscopio. Imagen de la izquierda: Endophytic retinoblastoma in a 19-month-old boy. Axial (a) and sagittal (b) 3D fast spin-echo MR images show three 1–2-mm vitreous seeds (arrows) in the right eye, a finding confirmed at ophthalmoscopy. Imagen de la derecha: Axial MR image obtained in a 19-year-old man shows an endophytic retinoblastoma (arrow) in the right eye. This form of retinoblastoma extends into the vitreous cavity. Associated vitreous seeding or hemorrhage may also be present.
- Vitreous hemorrhage may demonstrate high signal intensity on T1-weighted MR images and low signal intensity on T2-weighted MR images, a finding that may obscure the tumor. In such cases, the tumor is usually best delineated on T1-weighted MR imges without the use of gadolinium-based contrast material. Vitreous hemorrhage in a 2-year-old girl with endophytic retinoblastoma. Axial T1-weighted MR image (a) shows high signal intensity in the right globe, a finding indicative of subacute vitreous hemorrhage. This finding is less apparent at T2-weighted MR imaging . Retinoblastoma intraocular siembra vítrea Desprendimiento de retina y siembra subretiniana: las células de retinoblastoma proliferan hacia el espacio subretiniano entre la retina y coroides, especialmente en los exofiticos, retina desprendida asyacente al tumor. Hemorragia vítrea: reclasifica al tumor en grupo E.
- AUMENTA DE CALIBRE Y MAS TORTUOSOS. grow into the subretinal space with the possibility for subsequent retinal detachment, subretinal seeding, and choroidal invasion Pueden parecer desprendimientos de retina traumáticos. Axial MR image obtained in a 4-year-old boy shows an exophytic retinoblastoma (arrow) in the left eye. This form of retinoblastoma extends toward the choroid, involves the subretinal space, and often causes retinal detachment. However, retinal detachment is not specific to exophytic tumors and may also occur in endophytic retinoblastoma.
- Choroidal invasion in a 2-year-old boy with retinoblastoma. (a) Axial T1-weighted MR image shows a faint focal transscleral defect or irregularity (arrow) against bright orbital fat. (b) Axial contrast-enhanced T1-weighted MR image shows a thin area of normal enhancement in the left choroid (arrow), a finding not seen in the right globe due to the presence of tumor. Una invasion a coroides nos indica mal pronóstico, por q hay un alto riesgo de de que exista diseminación extraocular por diseminacion conigua, hematogena linfatica. en un t1 + c la coroides se ve como una capa fina hiperintensa, la esclera es hipointensa. Al haber una infiltación del tumor esta se ve con zonas focales con menor captación del contratse . Choroidal invasion is likely a poor prognostic marker for disease dissemination. Because the choroid is both a vascular supply for the eye and the last outer layer of the globe before the sclera, choroidal invasion by retinoblastoma cells likely increases the risk for hematogenous tumor dissemination and, perhaps, extension through the sclera or scleral emissary veins and into the retroocular space. de Graaf et al (27) provide evidence for an associatin between retinoblastoma tumor volume and the probability of choroidal infiltration. More generally, the risk for hematogenous and lymphatic dissemination increases substantially in patients with extraocular tumor (15,28–30). On contrast-enhanced T1-weighted MR images, the normal choroid is delineated as a thin and smooth line of enhancement in front of the hypointense sclera. Different MR imaging findings of choroidal invasion by a retinoblastoma have been described, such as thinning and focally decreased enhancement of the choroid compared with that of the contralateral globe and focal thickening and increased choroidal enhancement, which, in our experience, is more robust and more common (Fig 10).
- EL TUMOR CRECE A LO LARGO DE LA RETINA, Y SE VE COMO UNA MASA PLACOIDE. ESTA FORMA ES MUY DIFICIL DE DIAGNOSTICAR POR SU ASPECTO OFTALMOSCOPICO INUSUAL ( QUE SIMULA ENFERMEDADES INFLAMATORIAS O HEMORRAGICAS), SU TIPICA AUSENCIA DE CALCIFICACIONES Y SU APARICION NORMALMENTW FUERA DEL GRUPO DE EDADES NORMAL More rare growth patterns include diffuse infiltrating retinoblastoma, necrotic retinoblastoma associated with orbital cellulitis, and an even rarer pattern that results in phthisis bulbi.
- In retinoblastoma, extrascleral disease extends beyond the globe and is associated with a poor prognosis. In the St. Jude’s classification system, tumors that extend through the sclera are classified as stage III, and in the International Classification scheme, tumors with scleral invasion are classified as group E, extensive retinoblastoma, or, if spread is extrascleral, group F (6). Because most patients in the developed world receive an early diagnosis of retinoblastoma, the incidence of scleral infiltration and extrascleral extension is low; however, when they are present, the likelihood of metastases increases (19,31). The 3-year survival rate for patients with retinoblastoma with scleral infiltration is estimated to be 58%–77%; such patients may benefit from intensive systemic adjuvant therapy (31,32). On T1- and T2-weighted MR images, normal sclera is seen as a low-signal-intensity band between the enhancing chorioretinal layer and orbital fat, and a physiologic discontinuity is seen at the insertion site of the optic nerve. In patients with retinoblastoma, any other discontinuity within the dark band is indicative of scleral infiltration. Few studies have directly compared histopathologic findings of transscleral spread with MR imaging findings, and those that have been conducted are limited by small numbers of cases with transscleral spread (22,27). Generally, extrascleral spread of retinoblastoma is indicated by the presence of tumor within orbital fat, illustrating the importance of fat suppression in contrast-enhanced imaging of the orbit in patients undergoing evaluation for retinoblastoma (Fig 11). Tumors with extrascleral spread are classified as group F in the International Classification System (Table 1).
- Transscleral spread of retinoblastoma in a 3-month-old girl. (a) Axial T2-weighted MR image shows disruption of the sclera (arrow). Normal sclera appears as a uniform band of hypointensity on both T1- and T2- weighted images; any discontinuity or disruption of this band is highly suspicious for transscleral extension. (b) Axial contrast-enhanced T1-weighted MR image shows the scleral disruption (arrow) and abnormal enhancement of adjacent retrobulbar fat.
- Optic nerve involvement at MR imaging. (a) Axial MR image shows abnormal enhancement of the optic nerve with focal interruption of the normal chorioretinal area (arrow), a finding indicative of postlaminar optic nerve invasion. (b) Axial MR image shows abnormal enhancement of the optic nerve (arrow), which is asymmetric in size and enhancement and ill-defined. Areas of extrascleral and preorbital enhancement are also present. The tumor is confined to the orbit and inflammatory changes are present in the preseptal soft tissues. Histopathologic analysis confirmed postlaminar optic nerve involvement. Optic Nerve Involvement.—It is not believed that extension of a retinoblastoma into the retina overlying the optic disc increases mortality (14). However, it is universally accepted that involvement of the optic nerve beyond the lamina cribrosa is associated with a poor prognosis, with a mortality rate ranging from 13% to 89% depending on the degree of optic nerve involvement and whether the surgical margin is clear (14,15,29,33,34). In the past, an imaging diagnosis of optic nerve infiltration was a strong argument for initiating immediate tumor surgery. However, more recent reports of false-positive findings of optic nerve enhancement with no tumor cell involvement have led to more conservative approaches (27,35–37). Nevertheless, patients with preoperative imaging findings indicative of postlaminar optic nerve involvement often require enucleation with adjuvant chemotherapy if postlaminar optic nerve involvement or other histopathologic risk factors are confirmed (38). At MR imaging, optic nerve involvement is generally indicated by interruption of a linear area of enhancement at the choroidoretinal complex. However, detecting prelaminar optic nerve involvement at MR imaging is difficult, with an accuracy rate of 52%–79% across three studies and low sensitivity for depicting microscopic invasion (22,23,27). Tumor volume has been shown to be the best predictor of prelaminar invasion (27). In a study of retinoblastoma in 56 eyes by de Graaf et al (27), a tumor volume greater than 1.30 cm3 was associated with a 70% chance of prelaminar invasion, whereas a tumor volume less than 1.30 cm3 was associated with a 36% chance of invasion. Thickening of the enhancing choroidoretinal complex is also predictive of prelaminar invasion. In contrast, tumor location does not indicate optic nerve invasion
- Extraocular tumor spread in a 5-month-old boy. (a) Axial contrast-enhanced T1-weighted MR image shows an extensive periorbital soft-tissue abnormality and enhancement of retroorbital fat in the left eye (white arrows). The sclera is intact, and the lens is dislocated (black arrow), a result of the large size of the tumor. (b) Axial contrast-enhanced T2-weighted MR image shows additional tumor involving the right globe (arrow). At enucleation, the retrobulbar enhancement was shown to be secondary to inflammation rather than tumor infiltration. However, postlaminar optic nerve infiltration was present. Extraocular Tumor Spread.—Massive extraocular tumor spread is rare in the developed world. It may manifest clinically as a fungating mass, with swelling of periorbital soft tissues or proptosis. In most cases, subtle transscleral extension is not evident at direct clinical examination. Proptosis secondary to direct extension of an orbital retinoblastoma is not usually associated with extensive periocular or orbital inflammation. In the presence of proptosis, isolated inflammation may indicate sterile orbital cellulitis, which may be secondary to intraocular tumor necrosis (41). Evaluation of extraocular tumor spread is not possible at ophthalmoscopy. In such cases, MR imaging is extremely important in delineating the exact tumor extent and ruling out central nervous system disease before surgery (Fig 13). Complete surgical excision of local tumor is vital for improving the prognosis (42).
- El desarrollo de un tumor neuroblastico ectopico en la linea media de un paciente con retinoblastoma bilateral probablemnete representa un foco adicional deun cancer multicentrico mas que un segundo tumor primario o metastasis. El aspecto hiistologico de los retinoblastoma y piealoblastomas es identico Trilateral Retinoblastoma Patients with retinoblastoma who develop or present with intracranial tumors are considered to have trilateral retinoblastoma (Fig. 9-31). The majority of the intracranial tumors are located in the pineal region, although they may also occur in a suprasellar or parasellar location (Fig. 9-32).74 Survival inpatients with trilateral retinoblastoma is much lower than in patients with retinoblastoma without intracranial disease. In a literature review compiled by Kivela, 88% of patients with trilateral retinoblastoma died of their disease.74 Death is often secondary to dffuse leptomeningeal spread of tumor Trilateral Retinoblastoma.—Patients with the heritable form of retinoblastoma have a higher propensity for bilateral disease and a second primary malignancy. In these patients, the most common second primary malignancy is a midline intracranial tumor originating in the primitive neuroectodermal tissue. These tumors are most commonly localized to the suprasellar or pineal region and usually manifest later than primary tumors that arise in the globe. An intracranial tumor in a patient with retinoblastoma is referred to as trilateral retinoblastoma and is present in approximately 5%–7% of patients with bilateral disease (42,43). The median interval between the time a diagnosis of retinoblastoma in one or both globes is made and a brain tumor is discovered is 21 months; however, it may range from 6 months before a diagnosis of retinoblastoma to 141 months after the initial diagnosis of retinoblastoma (44). Suprasellar tumors are detected earlier than pineal tumors (44). Traditionally, trilateral retinoblastoma was fatal in almost all cases, although a recent study suggests that intensive chemotherapy may improve survival (45). At MR imaging, intracranial primary tumors are typically located in the midline, in the suprasellar or pineal region. An intraventricular location has also been described. Intracranial tumors demonstrate significant contrast enhancement. The normal pineal gland does not have a blood-brain barrier and, therefore, also demonstrates enhancement. A pineal gland tumor may be diagnosed on the basis of abnormal soft tissues within the pineal region (Fig 14). Hydrocephalus may be present, and leptomeningeal metastases and spinal lesions may be present or they may manifest later. MR imaging is helpful in screening patients with retinoblastoma for presymptomatic intracranial disease. Thus, screening and follow-up MR imaging in patients with retinoblastoma
- Presumed trilateral retinoblastoma. A, Axial CT scan shows bilateral calcified retinoblastomas (arrows). B, Axial CT scans with and without contrast enhancement show a large mass (M) in the region of the pineal gland with associated moderate hydrocephalus. This presumed pinealoma (retinoblastoma?) developed 2 years after external irradiation to both eyes through lateral ports
- Trilateral retinoblastoma in a 4-year-old girl with leptomeningeal metastases. (a, b) Axial T2-weighted MR image of the left eye (a) and contrast-enhanced T1-weighted MR image of the right eye (b) show bilateral retinoblastomas (arrow). (c) Sagittal contrast-enhanced T1-weighted MR image of the head shows a trilateral retinoblastoma (arrow).
- Leptomeningeal Disease.—Retinoblastoma may metastasize intracranially by way of the optic nerve, in which tumor cells infiltrate the subarachnoid space of the optic nerve sheath and disseminate into the cerebrospinal fluid of the brain and spinal cord, the most common route of metastatic spread (28). Less commonly, leptomeningeal involvea primary intracranial tumor in patients with trilateral retinoblastoma (Fig 14). MR imaging of the entire neuraxis should be performed to evaluate for leptomeningeal enhancement in patients with extraocular extension of a retinoblastoma or other indications of leptomeningeal spread. ment may be secondary to a primary intracranial tumor in patients with trilateral retinoblastoma (Fig 14). MR imaging of the entire neuraxis should be performed to evaluate for leptomeningeal enhancement in patients with extraocular extension of a retinoblastoma or other indications of leptomeningeal spread. Routes of Spread The natural course of untreated retinoblastoma follows one of five routes of progression: contiguous spread through the choroid, sclera, and orbit; extension along the optic nerve directly into the brain; invasion of the subarachnoid space and leptomeninges via the cerebrospinal fluid; hematogenous spread to bone marrow, bone, liver, and dissemination via conjunctiva through the lymphatic system.8 In the United States, the few patients with unilateral retinoblastoma who develop metastases usually have them at the time of diagnosis. The majority metastases occur within 5 years of diagnosis.18 Retinoblastoma may metastasise via direct spread into the orbit, along the optic nerve into the brain, or into the subarachnoid space resulting in leptomeningeal metastases. It can also haematogenously metastasise preferentially to the bone, bone marrow and liver. Rarely it will spread to regional lymph nodes 9.
- Trilateral retinoblastoma is the syndrome of bilateral retinoblastoma with a solitary midline intracranial tumor involving the pineal gland, suprasellar, or parasellar region.76 El-Nagger et al.77 reported an 11-month-old infant with retinoblastoma in both eyes and two distinct partially calcified intracranial tumors. A large mass involved the pineal gland region and there was a second tumor in the suprasellar region. The pineal mass was biopsied and was compatible with a neuroblastic tumor (pinealoblastoma). The authors coined the term tetralateral retinoblastoma for this case of two distinct midline intracranial neuroblastic tumors associated with bilateral retinoblastomas (Fig. 9-34).