Prognostic and predictive factors for the efficacy and safety of trastuzumab deruxtecan in HER2-positive gastric or gastroesophageal junction cancer.

BACKGROUND: Trastuzumab deruxtecan (T-DXd) is an antibody-drug conjugate targeting HER2-positive gastric cancer or gastroesophageal junction cancer (GC/GEJC). Although effective, T-DXd has notable toxicities, including interstitial lung disease (ILD). This study evaluated the efficacy, safety, and prognostic factors associated with T-DXd for GC/GEJC. METHODS: A retrospective observational study was conducted at our institution by reviewing medical records of patients treated with T-DXd until September 2023. Eligible patients had unresectable advanced or recurrent GC/GEJC, HER2 status of IHC 3 + or IHC 2 + /ISH-positive, and prior treatment with trastuzumab-containing regimen. RESULTS: Among the 101 patients analyzed, the initial T-DXd dose was 6.4 mg/kg in 77 patients and 5.4 mg/kg in 24 patients. The objective response rate was 54.3%, with a median PFS of 5.4 months and a median OS of 11.4 months. The significant prognostic factors for shorter PFS and OS included ECOG PS ≥ 1, presence of primary lesion, and peritoneal metastasis but not the initial T-DXd dose. ILD occurred in 14.9% of patients. Notably, higher T-DXd dose and smaller tumor burden were associated with a higher incidence of ILD. CONCLUSIONS: Several factors were associated with prognosis after T-DXd treatment in patients with GC/GEJC. Tumor burden is a potential risk factor for T-DXd-related ILD. Further studies are needed to optimize dosing based on tumor burden and to improve the therapeutic index.

2021 WHO Classification of Lung Cancer: Molecular Biology Research and Radiologic-Pathologic Correlation.

The 2021 World Health Organization (WHO) classification system for thoracic tumors (including lung cancer) contains several updates to the 2015 edition. Revisions for lung cancer include a new grading system for invasive nonmucinous adenocarcinoma that better reflects prognosis, reorganization of squamous cell carcinomas and neuroendocrine neoplasms, and description of some new entities. Moreover, remarkable advancements in our knowledge of genetic mutations and targeted therapies have led to a much greater emphasis on genetic testing than that in 2015. In 2015, guidelines recommended evaluation of only two driver mutations, ie, epidermal growth factor receptor (EGFR) mutations and anaplastic lymphoma kinase (ALK) fusions, in patients with nonsquamous non-small cell lung cancer. The 2021 guidelines recommend testing for numerous additional gene mutations for which targeted therapies are now available including ROS1, RET, NTRK1-3, KRAS, BRAF, and MET. The correlation of imaging features and genetic mutations is being studied. Testing for the immune biomarker programmed death ligand 1 is now recommended before starting first-line therapy in patients with metastatic non-small cell lung cancer. Because 70% of lung cancers are unresectable at patient presentation, diagnosis of lung cancer is usually based on small diagnostic samples (ie, biopsy specimens) rather than surgical resection specimens. The 2021 version emphasizes differences in the histopathologic interpretation of small diagnostic samples and resection specimens. Radiologists play a key role not only in evaluation of tumor and metastatic disease but also in identification of optimal biopsy targets. ©RSNA, 2024 Test Your Knowledge questions in the supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article.

Imaging of Malignant Minor Salivary Gland Tumors of the Head and Neck.

Minor salivary gland carcinomas (MSGCs) are nonminor tumors in the head and neck region and account for about half of all salivary gland carcinomas. Imaging evaluation based on the anatomy of minor salivary and mucous glands in the head and neck region as well as invasion patterns in each site helps in identifying optimal treatment modalities and planning suitable treatment strategies. MSGCs can be divided radiologically into localized and invasive subtypes on the basis of the clinical utility of such categorization. Characteristic invasion patterns of the invasive type include deep submucosal extension, bone marrow infiltration, and perineural spread, which are difficult to assess clinically. MSGCs easily invade adjacent structures because of their submucosal location and may spread along the muscles, nerves, periosteum, and dura mater. Moreover, the tumor may spread into the bone marrow without obvious bone destruction. In addition to imaging classification, examining the anatomy and distribution of the minor salivary glands, including the palatal, lingual, buccal, labial, and retromolar glands, as well as other mucous glands, including the glands of the sinonasal cavity and nasopharynx, lacrimal glands, ceruminous glands, laryngeal glands, and tracheal glands, facilitates MSGC diagnosis and tumor extension assessment. The authors review the precise anatomy of the minor salivary and mucous glands in the head and neck region, discuss the MSGC imaging classifications, and describe how to evaluate the extent of MSGCs in each site on the basis of the imaging classification and invasion patterns. ©RSNA, 2020.

Clinical usefulness of four-dimensional dynamic ventilation CT for borderline resectable locally advanced esophageal cancer.

PURPOSE: This study aimed to evaluate the clinical significance of four-dimensional dynamic ventilation CT (4DCT) for assessing resectability in borderline resectable locally advanced esophageal cancer (BR-LAEC) and confirmed the pathological validity of the 4DCT results in surgery without prior treatment. MATERIALS AND METHODS: We retrospectively reviewed 128 patients (107 men; median age, 68 [range, 43-89] years) diagnosed with BR-LAEC on initial conventional CT (i-CT). These patients were initially classified into three categories: BR1 (closer to resectable), BR2 (resectability not assessable), or BR3 (closer to unresectable). Subsequent 4DCT reclassified patients as either resectable or unresectable within 1 week of i-CT. We analyzed the diagnostic shift induced by 4DCT. Additionally, 18 patients who underwent surgery without prior treatment were evaluated using 4DCT and pathological outcomes. RESULTS: 4DCT reclassified patients with BR-LAEC as resectable (57.0%; 73/128) and unresectable (43.0%; 55/128). Of 53 patients initially classified as BR1, 32.1% (17/53) were reclassified as unresectable, and of 47 patients initially classified as BR3, 46.8% (22/47) were reclassified as resectable. Among 28 patients initially classified as BR2, 53.6% (15/27) were reclassified as resectable and 46.4% (13/27) as unresectable. In the surgery-only cohort of 18 patients, 9 were initially classified as BR1 and 9 as BR2, and all were reclassified as resectable. These patients were pathologically confirmed to have resectable disease. CONCLUSIONS: 4DCT may provide information complementary to that provided by initial conventional CT in assessing resectability among patients with BR-LAEC, and could be a useful adjunct tool for guiding clinical decisions in this patient population.

Radiologic feature of complications after artificial urinary sphincter implantation following total prostatectomy.

Incontinence following total prostatectomy for prostate cancer significantly impairs patient's quality of life. In severe cases, implantation of an artificial urinary sphincter (AUS) has shown favorable outcomes, enhancing continence by constricting the bulbous urethra. The AUS system consists of a pressure-maintaining balloon, control pump serving as the operational switch, cuff that constricts the urethra, and tubes and connectors that link these components, maintaining a continuous circuit through an internal pressure medium. Most instances of AUS dysfunction are attributed to circuit leaks leading to a reduction in internal pressure, which is identifiable on imaging by fluid accumulation around the circuit, balloon collapse, control pump deformation, and air within the circuit. When the AUS circuit is uncompromised, dysfunction may arise from issues such as the inability to compress the pump due to pain or displacement outside the scrotum or urinary tract obstruction caused by bladder hemorrhage/hematoma. Imaging plays a pivotal role in the evaluation of urinary tract injuries, hematomas/seromas, and infections associated with AUS placement or replacement. Understanding the function of AUS and its appearance on CT imaging is essential for accurately assessing AUS dysfunction and post-implantation complications, guiding clinical decision-making and improving patient care outcomes.

Computed tomography-based radiomic analysis for predicting pathological response and prognosis after neoadjuvant chemotherapy in patients with locally advanced esophageal cancer.

PURPOSE: Accurate prediction of prognosis and pathological response to neoadjuvant chemotherapy (NAC) is crucial for optimizing treatment strategies for patients with locally advanced esophageal cancer (LA-EC). This study aimed to investigate the use of radiomics for pretreatment CT in predicting the pathological response of patients with LA-EC to NAC. METHODS: Overall, 144 patients (145 lesions) with LA-EC who underwent pretreatment contrast-enhanced CT and then received NAC followed by surgery with pathological tumor regression grade (TRG) analysis were enrolled. The obtained dataset was randomly divided into training and validation cohorts using fivefold cross-validation. CT-based radiomic features were extracted followed by the feature selection process using the variance threshold, SelectKBest, and least absolute shrinkage and selection operator methods. The radiomic model was constructed using six machine learning classifiers, and predictive performance was evaluated using ROC curve analysis in the training and validation cohorts. RESULTS: All patients were divided into responders (n = 40, 28%) and non-responders (n = 104, 72%) based on the TRG results and a statistically significant split by overall survival analysis (0.899 [0.754-0.961] vs. 0.630 [0.510-0.729], respectively). There were no significant differences between responders and non-responders in terms of age, sex, tumor size, tumor location, or histopathology. The mean AUC of fivefold in the validation cohort was 0.720 (confidence interval [CI]: 0.594-0.982), and the best AUC of the radiomic model using logistic regression to predict the non-responders was 0.815 (CI: 0.626-1.000, sensitivity 0.620, specificity 0.860). CONCLUSION: A radiomic model derived from contrast-enhanced CT may help stratify chemotherapy effect prediction and improve clinical decision-making.

Computed tomography findings of hepatobiliary systems in patients with immune checkpoint inhibitor-induced liver injury.

PURPOSE: The incidence of immune checkpoint inhibitor (ICI)-induced liver injury has increased recently; however, its imaging characteristics remain unclear. This study aimed to characterize the computed tomography (CT) findings of ICI-induced liver injury. METHODS: This was a single-center retrospective study of patients with ICI-induced liver injury who underwent CT between January 2020 and December 2021. Two board-certified radiologists independently evaluated the CT findings of the patients before the start of ICI therapy (pre-CT) and at the onset of ICI-induced liver injury (post-CT) to determine the presence or absence of imaging findings suggestive of hepatitis and cholangitis. ICI-induced liver injury was classified into three categories based on the CT findings: hepatitis alone, cholangitis alone, and overlapped (cholangitis plus hepatitis). RESULTS: A total of 19 patients were included in this study. Bile duct dilatation, bile duct wall thickening, non-edematous gallbladder wall thickening, hepatomegaly, periportal edema, and gallbladder wall edema were observed in the post-CT images of 12 (63.2%), 9 (60%), 11 (57.9%), 8 (42.1%), 6 (31.6%), and 2 (10.5%) patients, respectively. Wall thickening in the perihilar, distal, intrapancreatic bile duct and the cystic duct were observed in 53.3%, 60%, 46.7%, and 26.7% of the study population, respectively. Regarding the classification of ICI-induced liver injury, cholangitis alone was most common (36.8%), followed by overlapped (26.3%) and hepatitis alone (26.3%). CONCLUSIONS: Patients with ICI-induced liver injury demonstrated a higher incidence of biliary abnormalities than hepatic abnormalities on CT images; nonetheless, future studies with larger sample sizes are needed to validate these findings.

The significance of SARC-F scores in predicting postoperative outcomes of older adults undergoing elective major surgery for urologic cancer.

BACKGROUND & AIMS: Recently, the strength, assistance with walking, rise from a chair, climb stairs, and falls (SARC-F) questionnaire has been developed to screen patients with signs of sarcopenia. However, its clinical benefit remains uncertain in elderly patients undergoing elective major surgeries. This study aimed to explore the role of the SARC-F questionnaire as a screening tool for patients who plan to undergo elective major surgery for urologic cancer and to also evaluate correlations of SARC-F scores with established indicators of sarcopenia. METHODS: This retrospective observational study enrolled 815 patients over 40 years of age undergoing elective major surgery for urologic cancer and who were screened with the SARC-F questionnaire, preoperatively. The primary endpoint was an association between SARC-F scores and postoperative ambulation failure. Here we define postoperative ambulation failure as a condition where a patient is unable to walk independently within 2 days after surgery and required physical rehabilitation or was transferred to other hospitals in a bedridden state. The secondary endpoint was an association between SARC-F scores and overall survival (OS). Psoas muscle density (PMD) and psoas muscle index (PMI) were calculated from abdominal computed tomography images, and their correlations with SARC-F scores grouped by sex. RESULTS: Of the 815 patients, 738 (91%) were male and the median age was 72 years. Although SARC-F scores weakly correlated with PMD in males and moderately correlated in females (ρ = -0.222 and ρ = -0.474, respectively), their correlation with PMI was negligible (ρ = -0.179 and ρ = -0.084, respectively). SARC-F scores successfully discriminate postoperative ambulation failure in both males and females with the respective area under the receiver operating characteristic curve of 0.856 and 0.813. Multivariate analysis also showed that SARC-F scores greater than 4 are an independent risk factor of postoperative ambulation failure along with older age, lower PMD, and poor performance status. SARC-F scores greater than 4 were significantly associated with a shorter OS in the whole cohort (P < 0.001) and a subgroup of patients undergoing radical cystectomy (P = 0.03; median follow-up of 515 days). CONCLUSIONS: The SARC-F questionnaire might be applicable to identify elderly patients at a higher risk of unfavourable outcomes after major urologic cancer surgery. A randomised controlled trial is necessary to confirm this finding.

Subtraction iodine imaging with area detector CT to improve tumor delineation and measurability of tumor size and depth of invasion in tongue squamous cell carcinoma.

PURPOSE: Tumor size and depth of invasion (DOI) are mandatory assessments for tumor classification in tongue cancer but are often non-assessable on CT due to dental artifacts. This study investigated whether subtraction iodine imaging (SII) would improve tumor delineation and measurability. MATERIALS AND METHODS: Fifty-seven consecutive patients with tongue cancer, who underwent scanning with a 320-row area detector CT with contrast administration and were treated with surgical resection, were retrospectively evaluated. CT was reconstructed with single-energy projection-based metallic artifact reduction (sCT). SII was generated by subtracting the pre-contrast volume scans from the post-contrast volume scans using a high-resolution deformable registration algorithm. MRI scans were also evaluated for comparing the ability of measurements. Two radiologists visually graded the tumor delineation using a 5-point scale. Tumor size and DOI were measured wherever possible. The tumor delineation score was compared using the Wilcoxon signed-rank method. Spearman's correlations between imaging and pathological measurements were calculated. Intraclass correlation coefficients of measurements between readers were estimated. RESULTS: The tumor delineation score was greater on sCT-plus-SII than on sCT alone (medians: 3 and 1, respectively; p < 0.001), with higher number of detectable cases observed with sCT-plus-SII (36/57 [63.2%]) than sCT alone (21/57 [36.8%]). Tumor size and DOI measurability were higher with sCT-plus-SII (29/57 [50.9%]) than with sCT alone (17/57 [29.8%]). MRI had the highest detectability (52/57 [91.2%]) and measurability (46/57 [80.7%]). Correlation coefficients between radiological and pathological tumor size and DOI were similar for sCT (0.83-0.88), sCT-plus-SII (0.78-0.84), and MRI (0.78-0.90). Intraclass correlation coefficients were higher than 0.95 for each modality. CONCLUSIONS: SII improves detectability and measurability of tumor size and DOI in patients with oral tongue squamous cell carcinoma, thus increasing the diagnostic potential. SII may also be beneficial for cases unevaluable on MRI due to artifacts or for patients with contraindications to MRI.

Evaluation of the morphological features and unfavorable prognostic impact of dirty necrosis in renal cell carcinoma.

PURPOSE: Tumor necrosis (TN) is one of the unfavorable prognostic factors in renal cell carcinoma (RCC). We identified two patterns of TN according to their morphology: dirty necrosis and ghost necrosis. We aimed to elucidate the morphological features and unfavorable prognostic impact of dirty necrosis in RCC. METHODS: A total of 261 tumors collected after nephrectomy, which were pathologically identified as RCC, were analyzed in this study. We classified TN as dirty necrosis or ghost necrosis and compared their clinicopathological features. We also assessed their morphological features using digitally analyzed slides. The correlation between tumor size and necrosis area or the number of necrotic foci was calculated. RESULTS: There were 77 tumors (30%) with TN, and the presence of TN was significantly associated with unfavorable clinicopathological factors. Thirty tumors (39%) had dirty necrosis, and 47 tumors (61%) had ghost necrosis. There were significantly higher numbers of unfavorable factors associated with dirty necrosis than with ghost necrosis. In dirty necrosis, both the TN area and the number of necrotic foci were correlated with tumor size (p < 0.001 and p = 0.003, respectively). However, in ghost necrosis, no correlation was found between tumor size and the number of necrotic foci (p = 0.58). Tumors (without stage IV) with dirty necrosis had a significantly shorter disease-free survival time than those with ghost necrosis and those without TN (p = 0.024 and p < 0.001, respectively). CONCLUSION: Dirty necrosis has potential as an unfavorable prognostic indicator of surgically resected RCC.

Extra-nodal extension in head and neck cancer: how radiologists can help staging and treatment planning.

Extranodal extension (ENE) is a significant prognostic factor in p16-negative head and neck squamous-cell carcinoma and is classified as N3b by the American Joint Committee on Cancer 8th edition. While most previous radiological studies have focused on the diagnostic performance of pathological ENE, radiologists should be able to provide more clinically relevant information on this entity. The purpose of this article is to review the clinical implications of ENE, to describe key imaging features of ENE with clinical and histopathological correlations and to discuss evaluation of ENE for clinical staging, treatment planning, and predicting the response to treatment. First, we discuss the basics of ENE, including definitions of pathological and clinical ENE and its association with imaging findings. Second, we describe the ENE extension pattern at each location according to level system. The crucial structures determining the choice of treatment include the deep fascia in the deep cervical layer, internal and common carotid arteries, and mediastinal structures. Invasion of the muscles, internal jugular vein, nerves, or mandible also affect the surgical procedure. Finally, we discuss assessment of nodal metastasis after chemoradiotherapy.

Imaging of extracranial head and neck lesions in cancer patients: a symptom-based approach.

Besides intracranial lesions, neurological symptoms are also caused in cancer patients by extracranial lesions in the head and neck. Common symptoms caused by such lesions include visual loss, visual field defect, diplopia, ptosis, sensory abnormalities of the head and neck region, facial nerve palsy, dysphagia, dysarthria, hoarseness, and syncope. Some cancer patients often have multiple cranial nerve involvement, which is associated with several syndromes such as jugular foramen syndrome. The main causes of cranial nerve dysfunction due to extracranial lesions include bone and nodal metastasis, perineural tumor spread, inflammation, and radiation injury. The location of the lesions causing the neurological symptom may be estimated by the symptoms and physical examination. However, CT/MRI is critical for reaching the final diagnosis and for treatment planning and management of the cancer patients. Moreover, early identification of the extracranial lesions may significantly affect patient care and alter outcomes. Thus, radiologists should be familiar with imaging findings of the common neurological disorders and the complex anatomy of the head and neck region, which should be checked in cancer patients with neurological symptoms.