Ovarian Cancer: An Evidence-Based, Easy-to-Use Prediction Rule to Optimize the Use of Follow-up Chest CT

PURPOSE

To create and validate an evidence-based prediction rule to optimize use of follow-up chest CT for ovarian cancer.

METHODS

In this Institutional Review Board-approved retrospective study performed at two academic medical centers, electronic medical records from January through December 2013 at center 1 (USA) and January 2012 through December 2013 at center 2 (South Korea) were searched to identify consecutive chest CTs performed within 5 years of initial cytoreductive surgery in patients with pathologically proven ovarian cancer. Three separate study cohorts were created: cohort 1, 316 CTs (in 150 patients) with high-grade serous ovarian cancer (HGSC) from center 1; cohort 2, 374 CTs (81 patients) with HGSC from center 2; and cohort 3, 87 CTs (56 patients) with non-HGSC histologies from center 1. A radiologist blinded to outcome of CT, using a prediction rule that utilized previously available information, categorized each CT into "high-risk" (stage 4 at presentation and/or preexisting abdominal disease [disease below diaphragmatic dome, visualized on abdominal CT]) or "low-risk" (neither of above). A blinded radiologist then reviewed chest CTs in random order to record thoracic metastases above the diaphragmatic dome, and outcome was compared with prediction rule risk category.

RESULTS

Among the three cohorts and in the total population, the prediction rule identified 94 of 316 (30%), 170 of 374 (45%), 53 of 87 (61%), and 317 of 777 (41%) CTs as "low-risk," respectively. The sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio were as follows: cohort 1: 95%, 35%, 24%, 97%, 1.46, 0.14; cohort 2: 88%, 53%, 29%, 95%, 1.87, 0.22; cohort 3: 88%, 66%, 21%, 98%, 2.59, 0.18; total population: 91%, 47%, 26%, 96%, 1.72, 0.19. False-negative rate in the three cohorts and in total population was 3 of 94 (3%), 8 of 170 (5%), 1 of 53 (2%), and 12 of 317 (4%); however, in each of these cases there was concurrent new abdominal disease.

CONCLUSIONS

The easy-to-use prediction rule helps avoid unnecessary chest CTs in patients with ovarian cancer with high sensitivity and negative predictive value, and with minimal risk of missing thoracoabdominal metastases.

Anorectal Cancer: Critical Anatomic and Staging Distinctions That Affect Use of Radiation Therapy

Although rectal and anal cancers are anatomically close, they are distinct entities with different histologic features, risk factors, staging systems, and treatment pathways. Imaging is at the core of initial clinical staging of these cancers and most commonly includes magnetic resonance imaging for local-regional staging and computed tomography for evaluation of metastatic disease. The details of the primary tumor and involvement of regional lymph nodes are crucial in determining if and how radiation therapy should be used in treatment of these cancers. Unfortunately, available imaging modalities have been shown to have imperfect accuracy for identification of nodal metastases and imaging features other than size. Staging of nonmetastatic rectal cancers is dependent on the depth of invasion (T stage) and the number of involved regional lymph nodes (N stage). Staging of nonmetastatic anal cancers is determined according to the size of the primary mass and the combination of regional nodal sites involved; the number of positive nodes at each site is not a consideration for staging. Patients with T3 rectal tumors and/or involvement of perirectal, mesenteric, and internal iliac lymph nodes receive radiation therapy. Almost all anal cancers warrant use of radiation therapy, but the extent and dose of the radiation fields is altered on the basis of both the size of the primary lesion and the presence and extent of nodal involvement. The radiologist must recognize and report these critical anatomic and staging distinctions, which affect use of radiation therapy in patients with anal and rectal cancers.

PD-1 Inhibitor-Related Pneumonitis in Advanced Cancer Patients: Radiographic Patterns and Clinical Course

PURPOSE

Investigate the clinical characteristics, radiographic patterns, and treatment course of PD-1 inhibitor-related pneumonitis in advanced cancer patients.

EXPERIMENTAL DESIGN

Among patients with advanced melanoma, lung cancer, or lymphoma treated in trials of nivolumab, we identified those who developed pneumonitis. Chest CT scans were reviewed to assess extent, distribution, and radiographic patterns of pneumonitis.

RESULTS

Among 170 patients treated in 10 different trials of nivolumab, 20 patients (10 melanoma, 6 lymphoma, and 4 lung cancer) developed pneumonitis. Five patients received nivolumab monotherapy, and 15 received combination therapy. The median time from therapy initiation to pneumonitis was 2.6 months. Radiographic pattern was cryptogenic organizing pneumonia (COP) in 13, nonspecific interstitial pneumonia (NSIP) in 3, hypersensitivity pneumonitis (HP) in 2, and acute interstitial pneumonia (AIP)/acute respiratory distress syndrome (ARDS) in 2 patients. The AIP/ARDS pattern had the highest grade, followed by COP, whereas NSIP and HP had lower grade (median grade: 3, 2, 1, 1, respectively; P = 0.006). The COP pattern was most common in all tumors and treatment regimens. Most patients (17/20; 85%) received corticosteroids, and 3 (15%) also required infliximab. Seven patients restarted nivolumab therapy; 2 of them developed recurrent pneumonitis and were successfully retreated with corticosteroids. One of the patients experienced a pneumonitis flare after completion of corticosteroid taper without nivolumab retreatment.

CONCLUSIONS

PD-1 inhibitor-related pneumonitis showed a spectrum of radiographic patterns, reflecting pneumonitis grades. COP was the most common pattern across tumor types and therapeutic regimens. Most patients were successfully treated with corticosteroids. Recurrent pneumonitis and pneumonitis flare were noted in a few patients. Clin Cancer Res; 22(24); 6051-60. ©2016 AACRSee related commentary by Castanon, p. 5956.

Patterns and Prognostic Importance of Hepatic Involvement in Patients with Serous Ovarian Cancer: A Single-Institution Experience with 244 Patients

Purpose To evaluate the frequency, patterns, and prognostic importance of metastatic hepatic involvement in serous ovarian cancer. Materials and Methods This institutional review board-approved retrospective study, with waived informed consent, included 244 patients with pathologically proven serous ovarian cancer (mean age ± standard deviation, 59 years ± 10.7; range 19-93 years). Electronic medical records and all available imaging studies over a median follow-up of 44 months (interquartile range [IQR], 27-70) were reviewed to identify the frequency of liver parenchymal invasion (LPI) from perihepatic peritoneal metastasis and hematogenous liver metastases. The associations and prognostic importance of LPI and hematogenous metastases were studied by using univariate and multivariate Cox proportional analysis. Results Eighty-four of 244 patients (34%) developed perihepatic metastases, of whom 55 (23%) developed LPI after median of 43 months (IQR, 25-63). Hematogenous hepatic metastases developed in 38 of 244 patients (16%) after median of 42 months (IQR, 26-64). At multivariate analysis, age (P = .008; hazard ratio [HR]: 1.03; 95% confidence interval [CI]: 1.009, 1.07) and suboptimal cytoreduction (P = .03; HR, 2.13; 95% CI: 1.12, 4.07) were associated with LPI. Increasing age (P = .01; HR, 1.04; 95% CI: 1.008, 1.08), high-grade tumor (P = .01; HR, 6.75; 95% CI: 1.44, 120.5), and advanced stage (P = .03; HR, 3.16; 95% CI: 1.94, 4.56) were associated with hematogenous metastases. Overall survival with and without LPI was similar (median, 80 months; IQR, 50-not reached vs 123 months; IQR, 49-279; P = .6). Hematogenous metastases were associated with significantly shorter survival at univariate (median 63 months, IQR 43-139 vs 145 months, IQR 50-not reached; P = .006) and multivariate analyses (P = .03; HR, 1.88; 95% CI: 1.14, 3.28). Conclusion Differentiating hematogenous metastases and LPI is important for radiologists; hematogenous metastases are associated with shorter survival, while LPI does not adversely affect survival and prognostically behaves like peritoneal disease. ^© RSNA, 2016.

Molecular targeted therapy in gynaecologic malignancies: primer for radiologists

The identification of characteristic genetic alteration in gynaecological malignancies has opened the door for molecular targeted therapy. The purpose of this review is to provide a primer for the radiologist on these agents with emphasis on the role of imaging in treatment response assessment and drug toxicities. The use of targeted therapy in gynaecological malignancies will likely increase in the future and make the role of the radiologist critical in response assessment and detection of toxicities.

Patterns of metastasis and recurrence in thymic epithelial tumours: longitudinal imaging review in correlation with histological subtypes

AIM

To determine the patterns of metastasis and recurrence in thymic epithelial tumours based on longitudinal imaging studies, and to correlate the patterns with World Health Organization (WHO) histological classifications.

MATERIALS AND METHODS

Seventy-seven patients with histopathologically confirmed thymomas (n=62) and thymic carcinomas (n=15) who were followed with cross-sectional follow-up imaging after surgery were retrospectively studied. All cross-sectional imaging studies during the disease course were reviewed to identify metastasis or recurrence. The sites of involvement and the time of involvement measured from surgery were recorded.

RESULTS

Metastasis or recurrence was noted in 24 (31%) of the 77 patients. Patients with metastasis or recurrence were significantly younger than those without (median age: 46 versus 60, respectively; p=0.0005), and more commonly had thymic carcinomas than thymomas (p=0.002). The most common site of involvement was the pleura (17/24), followed by the lung (9/24), and thoracic nodes (9/24). Abdominopelvic involvement was noted in 12 patients, most frequently in the liver (n=8). Lung metastasis was more common in thymic carcinomas than thymomas (p=0.0005). Time from surgery to the development of metastasis or recurrence was shortest in thymic carcinoma, followed by high-risk thymomas, and was longest in low-risk thymoma (median time in months: 25.1, 68.8, and not reached, respectively; p=0.0015).

CONCLUSIONS

The patterns of metastasis and recurrence of thymic epithelial tumours differ significantly across histological subgroups, with thymic carcinomas more commonly having metastasis with shorter length of time after surgery. The knowledge of different patterns of tumour spread may contribute to further understanding of the biological and clinical behaviours of these tumours.

Comparison of performance of various tumor response criteria in assessment of sunitinib activity in advanced gastrointestinal stromal tumors

PURPOSE

To compare the performance of various tumor response criteria (TRC) in the assessment of patients with advanced gastrointestinal stromal tumor (GIST) treated with sunitinib after failure of imatinib.

METHODS

Sixty-two participants with advanced GIST in two clinical trials received oral sunitinib after prior failure of imatinib (median duration 24 weeks; interquartile range 14-56) and were followed with contrast-enhanced computed tomography at baseline and thereafter at median intervals of 6 weeks (IRQ 6-9). Tumor response was prospectively determined using Response Evaluation Criteria in Solid Tumors (RECIST) 1.0, and retrospectively reassessed for comparison using RECIST 1.1, Choi criteria, and modified Choi (mChoi) criteria using the original target lesions. For mChoi criteria, progressive disease was defined as 20% increase in sum of the longest dimension, similar to RECIST 1.1. Clinical benefit rate (CBR; complete response, partial response, or stable disease ≥12 weeks) and progression-free survival were compared between various TRCs using kappa statistics.

RESULTS

While partial response as the best response was more frequent by Choi and mChoi criteria (50% each) than RECIST 1.1 (15%) and RECIST 1.0 (13%), CBR was similar between various TRCs (overall CBR 60%-77%, 77%-94% agreement between all TRC pairs). Time to best response was shorter for Choi and mChoi criteria (median 11 weeks each) compared to RECIST 1.1 and RECIST 1.0 (median 25 and 24 weeks, respectively). PFS was similar for RECIST 1.1, RECIST 1.0, and mChoi (median 35 weeks each), and shortest for Choi criteria (median 23 weeks).

CONCLUSIONS

CBR was similar among the various TRCs, although Choi criteria led to earlier determination of disease progression. Therefore, RECIST 1.1 and mChoi criteria may be preferred for response assessment in patients with advanced GIST.

Assessment of metastatic risk of gastric GIST based on treatment-naïve CT features

OBJECTIVE

To study whether the CT features of treatment-naïve gastric GIST may be used to assess metastatic risk.

METHODS

In this IRB approved retrospective study, with informed consent waived, contrast enhanced CT images of 143 patients with pathologically confirmed treatment-naïve gastric GIST (74 men, 69 women; mean age 61 years, SD ± 14) were reviewed in consensus by two oncoradiologists blinded to clinicopathologic features and clinical outcome and morphologic features were recorded. The metastatic spread was recorded using available imaging studies and electronic medical records (median follow up 40 months, interquartile range, IQR, 21-61). The association of maximum size in any plane (≤10 cm or >10 cm), outline (smooth or irregular/lobulated), cystic areas (≤50% or >50%), exophytic component (≤50% or >50%), and enhancing solid component (present or absent) with metastatic disease were analyzed using univariate (Fisher's exact test) and multivariate (logistic regression) analysis.

RESULTS

Metastatic disease developed in 42 (29%) patients (28 at presentation, 14 during follow-up); 23 (16%) patients died. On multivariate analysis, tumor size >10 cm (p = 0.0001, OR 9.9), irregular/lobulated outline (p = 0.001, OR 5.6) and presence of a enhancing solid component (p < 0.0001, OR 9.1) were independent predictors of metastatic disease. On subgroup analysis, an irregular/lobulated outline and an enhancing solid component were more frequently associated with metastases in tumors ≤5 cm and >5-≤10 cm (p < 0.05).

CONCLUSION

CT morphologic features can be used to assess the metastatic risk of treatment-naïve gastric GIST. Risk assessment based on pretreatment CT is especially useful for patients receiving neoadjuvant tyrosine kinase inhibitors and those with tumors <5 cm in size.

Multidetector computed tomography features of pancreatic metastases from leiomyosarcoma: Experience at a tertiary cancer center

AIM: To describe the multidetector computed tomography features of pancreatic metastasis from leiomyosarcoma (LMS).

METHODS: Between January 1995 and December 2012, 13 consecutive patients (11 women, 2 men; mean age of 57 years; range, 38-78 years) with pancreatic metastases from LMS were included in our study. Imaging features including location, number, largest dimension, tumor attenuation and enhancement characteristics, presence of necrosis, pancreatic ductal dilatation, common bile duct (CBD) dilatation, presence of pancreatitis, and atrophy were documented.

RESULTS: The most common site of origin of the pancreatic metastases from LMS was uterus (38.5%), followed by retroperitoneum (30.8%) and extremity (23.1%). None of the patients in our study had pancreas as the first site of metastasis. All patients developed pancreatic metastases at a median interval of 24 mo. Pancreatic metastases from LMS were solitary in 8/13 patients and multiple in 5/13 patients, had no predilection for any part of the pancreas, were hypovascular on arterial phase in 10/13 patients and associated with pancreatic duct dilatation in 3/13 patients. None had CBD dilatation. None of the pancreatic metastases in LMS cohort caused pancreatitis, and atrophy. Median duration of follow-up was 19 mo for LMS cohort during which two patients underwent resection of metastasis (median survival 45 mo) while the remaining underwent systemic therapy (median survival 13 mo).

CONCLUSION: Pancreatic metastases from LMS are often solitary and hypovascular masses and less commonly associated with pancreatic ductal dilatation, CBD dilatation, pancreatitis or pancreatic atrophy. Surgical resection of solitary LMS pancreatic metastasis can be considered due to the long survival of these patients.

CT predictors of overall survival at initial diagnosis in patients with stage IV colorectal cancer

PURPOSE

We investigated whether the initial CT distribution of metastatic disease is predictive of overall survival in patients with stage IV colorectal cancer.

MATERIALS AND METHODS

A retrospective study of 65 patients (37 males, 28 females, mean age 56, range 28-88 years) with stage IV colorectal cancer was derived from an institutional database. Inclusion criteria required KRAS mutation testing and pretreatment CT examinations to be available (65 abdomen/pelvis, 63 chest). Disease burden was jointly characterized by two radiologists in consensus. Median follow-up was 39 months (range 8-115 months). Survival was assessed using Cox proportional hazards models.

RESULTS

Univariate analysis showed that stratified site(s) of measurable disease and counts of measurable lesions ≥1 cm in the liver, peritoneum, and retroperitoneum were statistically significant risk factors for overall mortality [univariate HR 8.2 (CI 2.7-25.4) for isolated peritoneal disease, HR 1.11 per 5 lesions (CI 1.05-1.17) for liver lesions, HR 1.15 per lesion (CI 1.05-1.26) for peritoneal lesions, and HR 1.11 (CI 1.03-1.19) for retroperitoneal lymph nodes ≥1 cm in short axis]. The stratified site(s) of disease and counts of measurable liver lesions remained significant in the multivariate model (p < 0.0001 for isolated peritoneal disease and count of liver lesions). Thoracic metastases were not statistically significant predictors of overall mortality in this cohort.

CONCLUSION

This study identified site(s) of measurable metastasis and counts of measurable liver lesions as independent predictors of overall survival. These findings may have value for future prognostic assessments once validated in a larger, independent, and potentially prospective cohort.

Anti-PD-1 Inhibitor-Related Pneumonitis in Non-Small Cell Lung Cancer

The recent approval of two PD-1 inhibitors for the treatment of non-small cell lung cancer (NSCLC) has rapidly led to the widespread use of these agents in oncology practices. Pneumonitis has been recognized as a potentially life-threatening adverse event among NSCLC patients treated with PD-1 inhibitors; however, the detailed clinical and radiographic manifestations of this entity remain to be described. We report on two cases of anti-PD-1 pneumonitis in advanced NSCLC patients treated with nivolumab after its FDA approval. Both patients presented with ground-glass and reticular opacities and consolidations in a peripheral distribution on CT, demonstrating a radiographic pattern of cryptogenic organizing pneumonia. Consolidations were extensive and rapidly developed within 8 weeks of therapy in both cases. Both patients were treated with corticosteroids with subsequent improvement of respiratory symptoms and radiographic findings. One patient experienced recurrent pneumonitis after completing corticosteroid taper, or a "pneumonitis flare," in the absence of nivolumab retreatment, with subsequent improvement upon corticosteroid readministration. With the increasing use of immune checkpoint inhibitors in a growing number of tumor types, awareness of the radiographic and clinical manifestations of PD-1 inhibitor-related pneumonitis will be critical for the prompt diagnosis and management of this potentially serious adverse event.

Impact of histologic subtype and sarcomatoid transformation on metastasis in renal cell carcinoma: a single institute experience in 149 patients

PURPOSE

To compare the metastatic pattern and outcome of clear cell RCC (ccRCC) and papillary RCC (pRCC), and to assess the impact of sarcomatoid transformation on the disease spread and prognosis.

MATERIALS AND METHODS

This IRB-approved, HIPAA-compliant retrospective study included 149 consecutive patients (108 men; mean age 58 years; range 25-86) with metastatic RCC (ccRCC = 116, pRCC = 33), identified from imaging database. All available imaging studies and electronic records of these patients were reviewed to document pathological features, distribution and timing of metastasis, and survival. The metastatic pattern and survival was first compared between the ccRCC and pRCC groups, and then between those with and without sarcomatoid transformation; all 27 cases of sarcomatoid transformation occurred in the ccRCC group.

RESULTS

Metastases were noted at presentation in 62 (42%) and after median 13 months in the remaining 87 (58%) patients. Lymph nodes (134/149), lung (125/149), and bone (60/149) were the most common metastatic sites, which did not differ between the RCC subtypes. Pancreatic (p = 0.0014) and renal (p = 0.046) metastases were more common in ccRCC, lymphangitic spread (p = 0.0003) and peritoneal metastasis (p = 0.039) more common in pRCC. In ccRCC, sarcomatoid transformation was associated with high-grade tumors (p < 0.0001), more frequently demonstrated lymphangitic (p = 0.016), pleural (p = 0.0018), and peritoneal metastases (p = 0.0002), and had shorter metastasis-free survival and overall survival (log-rank test, p < 0.0001). In the absence of sarcomatoid transformation, ccRCC had longer metastasis-free interval (median 22 months compared to 6 months) (p = 0.0238) and overall survival (median survival 48 months vs. 25 months) (p = 0.0193) compared to pRCC.

CONCLUSION

Histologic subtype, as well as the presence of sarcomatoid transformation, affects the metastatic pattern and metastasis-free survival of RCC. In the absence of sarcomatoid transformation, ccRCC has a better outcome than pRCC.

Update on the imaging of malignant perivascular epithelioid cell tumors (PEComas)

Malignant perivascular epithelioid cell tumors (PEComas) are a histologic group of mesenchymal neoplasms that share a distinctive histological phenotype, the perivascular epithelioid cell. These tumors are known for their perivascular distribution. Malignant PEComas have a female predominance and are associated with aggressive disease and poor prognosis, making timely diagnosis critical to management. Imaging features of malignant PEComas are nonspecific and mimic other benign and malignant neoplasms. Surgery is the mainstay in the management of malignant PEComas. Promising novel molecular targeted therapies like m-TOR inhibitors have been shown to be effective in the metastatic setting. The aim of this review is to familiarize radiologists with the imaging appearances of and potential therapies for primary and metastatic malignant PEComa.

Multimodality imaging of osseous involvement In haematological malignancies

The purpose of this article is to provide a comprehensive review of the imaging features of osseous involvement in haematological malignancies. Osseous involvement can be seen in various haematological malignancies including lymphomas, plasma cell neoplasms, leukaemias and myeloproliferative neoplasms. Imaging plays a crucial role in initial diagnosis, staging and in the assessment of treatment response in these patients.

Cancer Imaging at the Crossroads of Precision Medicine: Perspective From an Academic Imaging Department in a Comprehensive Cancer Center

The authors propose one possible vision for the transformative role that cancer imaging in an academic setting can play in the current era of personalized and precision medicine by sharing a conceptual model that is based on experience and lessons learned designing a multidisciplinary, integrated clinical and research practice at their institution. The authors' practice and focus are disease-centric rather than imaging-centric. A "wall-less" infrastructure has been developed, with bidirectional integration of preclinical and clinical cancer imaging research platforms, enabling rapid translation of novel cancer drugs from discovery to clinical trial evaluation. The talents and expertise of medical professionals, scientists, and staff members have been coordinated in a horizontal and vertical fashion through the creation of Cancer Imaging Consultation Services and the "Adopt-a-Radiologist" campaign. Subspecialized imaging consultation services at the hub of an outpatient cancer center facilitate patient decision support and management at the point of care. The Adopt-a-Radiologist campaign has led to the creation of a novel generation of imaging clinician-scientists, fostered new collaborations, increased clinical and academic productivity, and improved employee satisfaction. Translational cancer research is supported, with a focus on early in vivo testing of novel cancer drugs, co-clinical trials, and longitudinal tumor imaging metrics through the imaging research core laboratory. Finally, a dedicated cancer imaging fellowship has been developed, promoting the future generation of cancer imaging specialists as multidisciplinary, multitalented professionals who are trained to effectively communicate with clinical colleagues and positively influence patient care.

Systemic treatment in breast cancer: a primer for radiologists

Abstract

Cytotoxic chemotherapy, hormonal therapy and molecular targeted therapy are the three major classes of drugs used to treat breast cancer. Imaging modalities such as computed tomography (CT), magnetic resonance imaging (MRI), ¹⁸F-FDG positron emission tomography (PET)/CT and bone scintigraphy each have a distinct role in monitoring response and detecting drug toxicities associated with these treatments. The purpose of this article is to elucidate the various systemic therapies used in breast cancer, with an emphasis on the role of imaging in assessing treatment response and detecting treatment-related toxicities.

Teaching Points

• Cytotoxic chemotherapy is often used in combination with HER2-targeted and endocrine therapies.

• Endocrine and HER2-targeted therapies are recommended in hormone-receptor- and HER2-positive cases.

• CT is the workhorse for assessment of treatment response in breast cancer metastases.

• Alternate treatment response criteria can help in interpreting pseudoprogression in metastasis.

• Unique toxicities are associated with cytotoxic chemotherapy and with endocrine and HER2-targeted therapies.