Imaging Characteristics of Driver Mutations in EGFR, KRAS, and ALK among Treatment-Naïve Patients with Advanced Lung Adenocarcinoma.

This study aimed to identify the computed tomography characteristics of treatment-naïve patients with lung adenocarcinoma and known driver mutations in EGFR, KRAS, or ALK. Patients with advanced lung adenocarcinoma (stage IIIB-IV) and known mutations in EGFR, KRAS, or ALK were assessed. The radiological findings for the main tumor and intra-thoracic status were retrospectively analyzed in each group, and the groups' characteristics were compared. We identified 265 treatment-naïve patients with non-small-cell carcinoma, who had EGFR mutations (n = 159), KRAS mutations (n = 55), or ALK rearrangements (n = 51). Among the three groups, we evaluated only patients with stage IIIB-IV lung adenocarcinoma who had EGFR mutations (n = 126), KRAS mutations (n = 35), or ALK rearrangements (n = 47). We found that ground-glass opacity at the main tumor was significantly more common among EGFR-positive patients, compared to ALK-positive patients (p = 0.009). Lymphadenopathy was significantly more common among ALK-positive patients, compared to EGFR-positive patients (p = 0.003). Extranodal invasion was significantly more common among ALK-positive patients, compared to EGFR-positive patients and KRAS-positive patients (p = 0.001 and p = 0.049, respectively). Lymphangitis was significantly more common among ALK-positive patients, compared to EGFR-positive patients (p = 0.049). Pleural effusion was significantly less common among KRAS-positive patients, compared to EGFR-positive patients and ALK-positive patients (p = 0.046 and p = 0.026, respectively). Lung metastases were significantly more common among EGFR-positive patients, compared to KRAS-positive patients and ALK-positive patients (p = 0.007 and p = 0.04, respectively). In conclusion, EGFR mutations were associated with ground-glass opacity, KRAS-positive tumors were generally solid and less likely to metastasize to the lung and pleura, and ALK-positive tumors tended to present with lymphadenopathy, extranodal invasion, and lymphangitis. These mutation-specific imaging characteristics may be related to the biological differences between these cancers

Multiple metallic stents placement for malignant hilar biliary obstruction: Perspective of a radiologist

In the palliative setting, the necessity of biliary drainage of both liver lobes for malignant hilar biliary obstruction remains controversial. However, bilateral biliary drainage is a reasonable option to prevent cholangitis of the undrained lobe and to preserve liver function during the course of chemotherapy. Bilateral biliary drainage can be accomplished by the percutaneous or endoscopic placement of multiple self-expandable metallic stents (SEMS). Although SEMS placement via bilateral (multiple) percutaneous routes is technically simple, multiple percutaneous transhepatic biliary drainage (PTBD) may lead to additional morbidity. SEMS placement via a single percutaneous route is a useful method; however, negotiation of a guidewire into the contralateral bile duct is occasionally impossible if the hilar angle between the right hepatic duct and left hepatic duct is acute. Percutaneous dual SEMS placement is generally performed using the stent-in-stent technique (T configuration or Y configuration) or the side-by-side technique. In addition, the crisscross technique has been reported as being a useful method for trisegmental drainage. The side-to-end technique is also useful for multiple SEMS placement. In the future, the combination of percutaneous intervention and endoscopic ultrasonography-guided procedures may be effective in the management of malignant hilar biliary obstruction

Imaging Characteristics of Driver Mutations in <i>EGFR</i>, <i>KRAS</i>, and <i>ALK</i> among Treatment-Naïve Patients with Advanced Lung Adenocarcinoma

<div><p>This study aimed to identify the computed tomography characteristics of treatment-naïve patients with lung adenocarcinoma and known driver mutations in <i>EGFR</i>, <i>KRAS</i>, or <i>ALK</i>. Patients with advanced lung adenocarcinoma (stage IIIB–IV) and known mutations in <i>EGFR</i>, <i>KRAS</i>, or <i>ALK</i> were assessed. The radiological findings for the main tumor and intra-thoracic status were retrospectively analyzed in each group, and the groups’ characteristics were compared. We identified 265 treatment-naïve patients with non-small-cell carcinoma, who had <i>EGFR</i> mutations (n = 159), <i>KRAS</i> mutations (n = 55), or <i>ALK</i> rearrangements (n = 51). Among the three groups, we evaluated only patients with stage IIIB–IV lung adenocarcinoma who had <i>EGFR</i> mutations (n = 126), <i>KRAS</i> mutations (n = 35), or <i>ALK</i> rearrangements (n = 47). We found that ground-glass opacity at the main tumor was significantly more common among <i>EGFR</i>-positive patients, compared to <i>ALK</i>-positive patients (<i>p</i> = 0.009). Lymphadenopathy was significantly more common among <i>ALK</i>-positive patients, compared to <i>EGFR</i>-positive patients (<i>p</i> = 0.003). Extranodal invasion was significantly more common among <i>ALK</i>-positive patients, compared to <i>EGFR</i>-positive patients and <i>KRAS</i>-positive patients (<i>p</i> = 0.001 and <i>p</i> = 0.049, respectively). Lymphangitis was significantly more common among <i>ALK</i>-positive patients, compared to <i>EGFR</i>-positive patients (<i>p</i> = 0.049). Pleural effusion was significantly less common among <i>KRAS</i>-positive patients, compared to <i>EGFR</i>-positive patients and <i>ALK</i>-positive patients (<i>p</i> = 0.046 and <i>p</i> = 0.026, respectively). Lung metastases were significantly more common among <i>EGFR</i>-positive patients, compared to <i>KRAS</i>-positive patients and <i>ALK</i>-positive patients (<i>p</i> = 0.007 and <i>p</i> = 0.04, respectively). In conclusion, <i>EGFR</i> mutations were associated with ground-glass opacity, <i>KRAS</i>-positive tumors were generally solid and less likely to metastasize to the lung and pleura, and <i>ALK</i>-positive tumors tended to present with lymphadenopathy, extranodal invasion, and lymphangitis. These mutation-specific imaging characteristics may be related to the biological differences between these cancers.</p></div

Patients’ characteristics.

<p>Patients’ characteristics.</p

The relative distributions of the main tumor and intra-thoracic characteristics among stage IIIB–IV patients with lung adenocarcinoma.

<p>*<i>P</i> < 0.05; † <i>P</i> < 0.01; ‡ <i>P</i> < 0.005.</p