How Imaging Advances Are Defining the Future of Precision Radiation Therapy.

Radiation therapy is fundamental in the treatment of cancer. Imaging has always played a central role in radiation oncology. Integrating imaging technology into irradiation devices has increased the precision and accuracy of dose delivery and decreased the toxic effects of the treatment. Although CT has become the standard imaging modality in radiation therapy, the development of recently introduced next-generation imaging techniques has improved diagnostic and therapeutic decision making in radiation oncology. Functional and molecular imaging techniques, as well as other advanced imaging modalities such as SPECT, yield information about the anatomic and biologic characteristics of tumors for the radiation therapy workflow. In clinical practice, they can be useful for characterizing tumor phenotypes, delineating volumes, planning treatment, determining patients' prognoses, predicting toxic effects, assessing responses to therapy, and detecting tumor relapse. Next-generation imaging can enable personalization of radiation therapy based on a greater understanding of tumor biologic factors. It can be used to map tumor characteristics, such as metabolic pathways, vascularity, cellular proliferation, and hypoxia, that are known to define tumor phenotype. It can also be used to consider tumor heterogeneity by highlighting areas at risk for radiation resistance for focused biologic dose escalation, which can impact the radiation planning process and patient outcomes. The authors review the possible contributions of next-generation imaging to the treatment of patients undergoing radiation therapy. In addition, the possible roles of radio(geno)mics in radiation therapy, the limitations of these techniques, and hurdles in introducing them into clinical practice are discussed. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Primary Rectal Tumor With Extensive Choriocarcinoma Differentiation in a Woman With Lung, Liver and Disseminated Peritoneal Disease: A Primary Rectal Adenocarcinoma With Extensive Choriocarcinoma Differentiation or Primary Rectal Choriocarcinoma?

Primary rectal adenocarcinoma with extensive choriocarcinomatous differentiation is a rare neoplasm, with only sporadic cases reported worldwide. The prognosis is typically poor, and no standard therapy has been established for this tumor. We report a case of a 63-year-old woman who presented with lower abdominal and pelvic discomfort, as well as rectal bleeding. Endoscopy revealed a rectal tumor. She was diagnosed with primary rectal adenocarcinoma with extensive choriocarcinomatous differentiation, accompanied by liver metastasis and peritoneal carcinomatosis. The immunohistochemical profile demonstrated strong and diffuse positivity for keratin (AE1/AE3), beta-human chorionic gonadotropin (ß-HCG), p53, MYC, p16, and Ki-67. Molecular analysis indicated mutations in KRAS, TP53, and PI3KCA. Despite the tumor's profile, the serum ß-HCG level was not elevated. A chemotherapy regimen for metastatic colorectal adenocarcinoma was initiated, but there was a poor response, with rapid tumor progression. The patient survived for only 5 months postdiagnosis. We discuss the histopathological, immunohistochemical, and molecular findings, emphasizing their relevance to the differential diagnosis of neoplasms with choriocarcinomatous differentiation.

Angiomiolipoma epitelioide/PEComa hepático e hiperplasia nodular focal en una paciente con antecedentes de melanoma cutáneo / Hepatic epithelioid angiomyolipoma/PEComa and focal nodular hyperplasia in a patient with a previous history of cutaneous melanoma

Los tumores de células epitelioides perivasculares (PEComas) hepáticos son lesiones mesenquimales poco comunes. La ocurrencia simultánea de PEComas y otras lesiones hepáticas es inusual, con solo dos reportes de casos adicionales en la literatura inglesa. Reportamos un caso de PEComa primario hepático asociado con una hiperplasia nodular focal en una paciente con antecedentes de melanoma cutáneo. El diagnóstico radiológico fue sugestivo de adenoma hepático, por lo que se realizó una resección segmentaria hepática. El tumor estaba constituido por una proliferación de células epitelioides, tejido adiposo y fibras de músculo liso entremezcladas con vasos sanguíneos. Las células tumorales mostraron positividad difusa e intensa para HMB-45, Melan-A y actina de músculo liso, siendo negativas para Hepatocyte, S100, MITF y BRAF. No se detectó mutación BRAFV600 en el estudio por biología molecular. El diagnóstico patológico final fue de angiomiolipoma epitelioide hepático/PEComa. Se realiza una discusión del diagnóstico diferencial de los PEComas hepáticos

Hepatic perivascular epithelioid cell tumors (PEComas) are uncommon mesenchymal neoplasms. PEComas concurrent with other hepatic lesions is a very rare occurrence, with only two previously reported cases. We report a primary hepatic PEComa associated with focal nodular hyperplasia in a patient with a previous history of cutaneous melanoma. Diagnostic imaging studies suggested a hepatic adenoma and the patient underwent a segmentectomy. The tumor was mainly composed of epithelioid cells, adipose tissue and smooth muscle fibers intermixed with blood vessels. The neoplastic cells were diffusely immunoreactive for HMB-45, Melan-A and smooth muscle actin, but not for Hepatocyte, S100, MITF or BRAF. Molecular studies were negative for BRAFV600 mutation. The final diagnosis was hepatic epithelioid angiomyolipoma/PEComa. The differential diagnosis of hepatic PEComa is discussed

[Hepatic epithelioid angiomyolipoma/PEComa and focal nodular hyperplasia in a patient with a previous history of cutaneous melanoma]. / Angiomiolipoma epitelioide/PEComa hepático e hiperplasia nodular focal en una paciente con antecedentes de melanoma cutáneo.

Hepatic perivascular epithelioid cell tumors (PEComas) are uncommon mesenchymal neoplasms. PEComas concurrent with other hepatic lesions is a very rare occurrence, with only two previously reported cases. We report a primary hepatic PEComa associated with focal nodular hyperplasia in a patient with a previous history of cutaneous melanoma. Diagnostic imaging studies suggested a hepatic adenoma and the patient underwent a segmentectomy. The tumor was mainly composed of epithelioid cells, adipose tissue and smooth muscle fibers intermixed with blood vessels. The neoplastic cells were diffusely immunoreactive for HMB-45, Melan-A and smooth muscle actin, but not for Hepatocyte, S100, MITF or BRAF. Molecular studies were negative for BRAFV600 mutation. The final diagnosis was hepatic epithelioid angiomyolipoma/PEComa. The differential diagnosis of hepatic PEComa is discussed.

Advanced Imaging Techniques in Evaluation of Colorectal Cancer.

Imaging techniques are clinical decision-making tools in the evaluation of patients with colorectal cancer (CRC). The aim of this article is to discuss the potential of recent advances in imaging for diagnosis, prognosis, therapy planning, and assessment of response to treatment of CRC. Recent developments and new clinical applications of conventional imaging techniques such as virtual colonoscopy, dual-energy spectral computed tomography, elastography, advanced computing techniques (including volumetric rendering techniques and machine learning), magnetic resonance (MR) imaging-based magnetization transfer, and new liver imaging techniques, which may offer additional clinical information in patients with CRC, are summarized. In addition, the clinical value of functional and molecular imaging techniques such as diffusion-weighted MR imaging, dynamic contrast material-enhanced imaging, blood oxygen level-dependent imaging, lymphography with contrast agents, positron emission tomography with different radiotracers, and MR spectroscopy is reviewed, and the advantages and disadvantages of these modalities are evaluated. Finally, the future role of imaging-based analysis of tumor heterogeneity and multiparametric imaging, the development of radiomics and radiogenomics, and future challenges for imaging of patients with CRC are discussed. Online supplemental material is available for this article. ©RSNA, 2018.

Micrometástasis en ganglios peripancreáticos por carcinoma mamario en paciente con adenocarcinoma ductal pancreático / Peripancreatic lymph node micrometastases from a mammary carcinoma in a patient with pancreatic ductal adenocarcinoma

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Advanced imaging of colorectal cancer: From anatomy to molecular imaging.

UNLABELLED: Imaging techniques play a key role in the management of patients with colorectal cancer. The introduction of new advanced anatomical, functional, and molecular imaging techniques may improve the assessment of diagnosis, prognosis, planning therapy, and assessment of response to treatment of these patients. Functional and molecular imaging techniques in clinical practice may allow the assessment of tumour-specific characteristics and tumour heterogeneity. This paper will review recent developments in imaging technologies and the evolving roles for these techniques in colorectal cancer. TEACHING POINTS: • Imaging techniques play a key role in the management of patients with colorectal cancer. • Advanced imaging techniques improve the evaluation of these patients. • Functional and molecular imaging allows assessment of tumour hallmarks and tumour heterogeneity.

Leiomiosarcoma con patrón fusocelular y epitelioide en cuerpo del páncreas. Utilidad de la inmunohistoquímica en el diagnóstico diferencial de las neoplasias mesenquimales pancreáticas / Leiomyosarcoma with spindle and epithelioid pattern in the pancreatic body. The role of immunohistochemistry in the differential diagnosis of mesenchymal pancreatic tumours

Los leiomiosarcomas pancreáticos son neoplasias altamente agresivas con muy mal pronóstico. Se describe un caso de un paciente masculino de 78 años de edad que presenta un tumor abdominal en el que los estudios radiológicos confirmaron el origen primario en el páncreas. El estudio morfológico mostró un sarcoma con morfología fusocelular y epitelioide, con un perfil inmunohistoquímico positivo para actina músculo liso y desmina con negatividad para miogenina, h-caldesmon, CD117, DOG-1, S100, MyoD1, cromogranina-A, HMB-45, Melan A y EBV, confirmando el diagnóstico de leiomiosarcoma fusocelular y epitelioide. Se discute el diagnóstico diferencial con otras neoplasias mesenquimales pancreáticas(AU)

Pancreatic leiomyosarcoma is a highly aggressive malignancy with a poor prognosis. We report a case of a 78-year-old man with an abdominal mass which was diagnosed radiologically as a primary pancreatic sarcoma. Histopathology revealed a spindle/epithelioid cells morphology and immunohistochemistry showed strong positivity for smooth muscle actin and desmin, with negative results for myogenin, h-caldesmon, CD117, DOG-1, S100, MyoD1, chromogranin-A, HMB-45, Melan-A and EBV. The diagnosis of spindle and epithelioid leiomyosarcoma was confirmed. The differential diagnosis with pancreatic mesenchymal lesions is discussed(AU)

Oncología ginecológica: diagnóstico, estadificación y seguimiento de las neoplasias de origen ginecológico / Gynecological oncology: diagnosis, staging and follow-up of neoplasias of gynecological origin

El gran avance de los métodos de Diagnóstico por Imagen alcanzado en los últimos años, ha permitido tener acceso al conocimiento más exacto de la patología ginecológica neoformativa tanto en lo que respecta a su diagnóstico como al estudio de extensión de la enfermedad que determina directamente la terapéutica a seguir. Precisamente el desarrollo de las diferentes técnicas diagnósticas, con sus ventajas y limitaciones, hace necesaria una revisión y puesta al día de su uso combinado para obtener el mayor rendimiento posible. Nuestro objetivo en el presente trabajo ha sido mostrar las distintas formas de presentación de los diferentes tumores de origen ginecológico: útero, ovario, trompas, vagina y vulva y lo que el radiólogo puede esperar de las técnicas actuales de Diagnóstico por Imagen para optimizar su uso y conseguir diagnósticos más precoces y estudios de extensión más precisos (AU)