Measuring Inter-observer Agreement in Contour Delineation of Medical Imaging in a Dummy Run Using Fleiss’ Kappa

SummaryBackground: In medical imaging used for planning of radiation therapy, observers delineate contours of a treatment volume in a series of images of uniform slice thickness.Objective: To summarize agreement in contouring between an arbitrary number of observers by a single number, we generalized the kappa index proposed by Zijdenbos et al. (1994).Methods: Observers characterized voxels by allocating them to one of two categories, inside or outside the contoured region. Fleiss’ kappa was used to measure association between n indistinguishable observers. Given the number Vi of voxels contoured by exactly i observers (i = 1, …, n), the resulting overall kappa is representable as a ratio of weighted sums of the Vi .Results: Overall kappa was applied to analyze inter-center variations in a multicenter trial on radiotherapy planning in patients with locally advanced lung cancer. A contouring dummy run was performed within the quality assurance program. Contouring was done twice, once before and once after a training program. Observer agreement was enhanced from 0.59 (with a 95% confidence interval (CI) of 0.51 – 0.67) to 0.69 (95% CI 0.59 – 0.78)Conclusion: By contrast to average pairwise indices, overall kappa measures observer agreement for more than two observers using the full information about overlapping volumes, while not distinguishing between observers. It is particularly adequate for measuring observer agreement when identification of observers is not possible or desirable and when there is no gold standard.

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Deep inspiration breath hold in locally advanced lung cancer radiotherapy: validation of intrafractional geometric uncertainties in the INHALE trial

British Journal of Radiology ◽

10.1259/bjr.20190569 ◽

2019 ◽

Vol 92 (1104) ◽

pp. 20190569 ◽

Cited By ~ 4

Author(s):

Mirjana Josipovic ◽

Marianne C Aznar ◽

Jakob B Thomsen ◽

Jonas Scherman ◽

Sidsel MS Damkjaer ◽

...

Keyword(s):

Lung Cancer ◽

Pilot Study ◽

Locally Advanced ◽

Target Position ◽

Optical Tracking ◽

Radiotherapy Planning ◽

Advanced Lung Cancer ◽

Breath Hold ◽

Deep Inspiration ◽

Deep Inspiration Breath Hold

Objectives: Patients with locally advanced non-small cell lung cancer (NSCLC) were included in a prospective trial for radiotherapy in deep inspiration breath hold (DIBH). We evaluated DIBH compliance and target position reproducibility. Methods: Voluntary, visually guided DIBHs were performed with optical tracking. Patients underwent three consecutive DIBH CT scans for radiotherapy planning. We evaluated the intrafractional uncertainties in the position of the peripheral tumour, lymph nodes and differential motion between them, enabling PTV margins calculation. Patients who underwent all DIBH imaging and had tumour position reproducibility <8 mm were up-front DIBH compliant. Patients who performed DIBHs throughout the treatment course were overall DIBH compliant. Clinical parameters and DIBH-related uncertainties were validated against our earlier pilot study. Results: 69 of 88 included patients received definitive radiotherapy. 60/69 patients (87%) were up-front DIBH compliant. DIBH plan was not superior in seven patients and three lost DIBH ability during the treatment, leaving 50/69 patients (72%) overall DIBH compliant. The systematic and random errors between consecutive DIBHs were small but differed from the pilot study findings. This led to slightly different PTV margins between the two studies. Conclusions: DIBH compliance and reproducibility was high. Still, this validation study highlighted the necessity of designing PTV margins in larger, representative patient cohorts. Advances in knowledge: We demonstrated high DIBH compliance in locally advanced NSCLC patients. DIBH does not eliminate but mitigates the target position uncertainty, which needs to be accounted for in treatment margins. Margin design should be based on data from larger representative patient groups.

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The Orientation of Gastric Biopsy Samples Improves the Interobserver Agreement of the OLGA Staging System

Journal of Gastrointestinal and Liver Diseases ◽

10.15403/jgld.2014.1121.264.olg ◽

2017 ◽

Vol 26 (4) ◽

pp. 351-356 ◽

Cited By ~ 5

Author(s):

Bogdan Cotruta ◽

Cristian Gheorghe ◽

Razvan Iacob ◽

Mona Dumbrava ◽

Cristina Radu ◽

...

Keyword(s):

Intestinal Metaplasia ◽

Lamina Propria ◽

Case Series ◽

Gastric Biopsy ◽

Gastric Atrophy ◽

Observer Agreement ◽

Gastric Body ◽

Kappa Index ◽

Gastric Biopsies

Background & Aims: Evaluation of severity and extension of gastric atrophy and intestinal metaplasia is recommended to identify subjects with a high risk for gastric cancer. The inter-observer agreement for the assessment of gastric atrophy is reported to be low. The aim of the study was to evaluate the inter-observer agreement for the assessment of severity and extension of gastric atrophy using oriented and unoriented gastric biopsy samples. Furthermore, the quality of biopsy specimens in oriented and unoriented samples was analyzed.Methods: A total of 35 subjects with dyspeptic symptoms addressed for gastrointestinal endoscopy that agreed to enter the study were prospectively enrolled. The OLGA/OLGIM gastric biopsies protocol was used. From each subject two sets of biopsies were obtained (four from the antrum, two oriented and two unoriented, two from the gastric incisure, one oriented and one unoriented, four from the gastric body, two oriented and two unoriented). The orientation of the biopsy samples was completed using nitrocellulose filters (Endokit®, BioOptica, Milan, Italy). The samples were blindly examined by two experienced pathologists. Inter-observer agreement was evaluated using kappa statistic for inter-rater agreement. The quality of histopathology specimens taking into account the identification of lamina propria was analyzed in oriented vs. unoriented samples. The samples with detectable lamina propria mucosae were defined as good quality specimens. Categorical data was analyzed using chi-square test and a two-sided p value <0.05 was considered statistically significant.Results: A total of 350 biopsy samples were analyzed (175 oriented / 175 unoriented). The kappa index values for oriented/unoriented OLGA 0/I/II/III and IV stages have been 0.62/0.13, 0.70/0.20, 0.61/0.06, 0.62/0.46, and 0.77/0.50, respectively. For OLGIM 0/I/II/III stages the kappa index values for oriented/unoriented samples were 0.83/0.83, 0.88/0.89, 0.70/0.88 and 0.83/1, respectively. No case of OLGIM IV stage was found in the present case series. Good quality histopathology specimens were described in 95.43% of the oriented biopsy samples, and in 89.14% of the unoriented biopsy samples, respectively (p=0.0275).Conclusion: The orientation of gastric biopsies specimens improves the inter-observer agreement for the assessment of gastric atrophy.Key words: – – – .Abbreviations: H. pylori: Helicobacter pylori; OLGA: operative link for gastritis assessment; OLGIM: operative link on intestinal metaplasia assessment.

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Charged Particle and Conventional Radiotherapy: Current Implications as Partner for Immunotherapy

Cancers ◽

10.3390/cancers13061468 ◽

2021 ◽

Vol 13 (6) ◽

pp. 1468

Author(s):

Damiënne Marcus ◽

Relinde I. Y. Lieverse ◽

Carmen Klein ◽

Amir Abdollahi ◽

Philippe Lambin ◽

...

Keyword(s):

Charged Particle ◽

Clinical Success ◽

Immune Therapy ◽

Locally Advanced ◽

Optimal Dose ◽

High Energy ◽

Advanced Lung Cancer ◽

Antitumor Effects ◽

Immunological Effects ◽

Tumor Immunogenicity

Radiotherapy (RT) has been shown to interfere with inflammatory signals and to enhance tumor immunogenicity via, e.g., immunogenic cell death, thereby potentially augmenting the therapeutic efficacy of immunotherapy. Conventional RT consists predominantly of high energy photon beams. Hypofractionated RT regimens administered, e.g., by stereotactic body radiation therapy (SBRT), are increasingly investigated in combination with cancer immunotherapy within clinical trials. Despite intensive preclinical studies, the optimal dose per fraction and dose schemes for elaboration of RT induced immunogenic potential remain inconclusive. Compared to the scenario of combined immune checkpoint inhibition (ICI) and RT, multimodal therapies utilizing other immunotherapy principles such as adoptive transfer of immune cells, vaccination strategies, targeted immune-cytokines and agonists are underrepresented in both preclinical and clinical settings. Despite the clinical success of ICI and RT combination, e.g., prolonging overall survival in locally advanced lung cancer, curative outcomes are still not achieved for most cancer entities studied. Charged particle RT (PRT) has gained interest as it may enhance tumor immunogenicity compared to conventional RT due to its unique biological and physical properties. However, whether PRT in combination with immune therapy will elicit superior antitumor effects both locally and systemically needs to be further investigated. In this review, the immunological effects of RT in the tumor microenvironment are summarized to understand their implications for immunotherapy combinations. Attention will be given to the various immunotherapeutic interventions that have been co-administered with RT so far. Furthermore, the theoretical basis and first evidences supporting a favorable immunogenicity profile of PRT will be examined.

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Survival analysis of pathological complete response of locally advanced lung cancer after neoadjuvant treatment

General Thoracic and Cardiovascular Surgery ◽

10.1007/s11748-020-01584-z ◽

2021 ◽

Author(s):

Özgür İşgörücü ◽

Necati Citak

Keyword(s):

Lung Cancer ◽

Survival Analysis ◽

Pathological Complete Response ◽

Locally Advanced ◽

Neoadjuvant Treatment ◽

Complete Response ◽

Advanced Lung Cancer ◽

Locally Advanced Lung Cancer

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151 Safety and survival of high dose palliative radiotherapy for locally advanced lung cancer

Lung Cancer ◽

10.1016/s0169-5002(14)70152-7 ◽

2014 ◽

Vol 83 ◽

pp. S55-S56

Author(s):

S.M. O'Cathail ◽

F.M. Buffa ◽

G.S. Higgins ◽

N. Panakis

Keyword(s):

Lung Cancer ◽

Locally Advanced ◽

Palliative Radiotherapy ◽

Advanced Lung Cancer ◽

High Dose ◽

Locally Advanced Lung Cancer

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Clinical Application of a Hybrid RapidArc Radiotherapy Technique for Locally Advanced Lung Cancer

Technology in Cancer Research & Treatment ◽

10.1177/1533034616670273 ◽

2016 ◽

Vol 16 (2) ◽

pp. 224-230

Author(s):

Scott R. Silva ◽

Murat Surucu ◽

Jennifer Steber ◽

Matthew M. Harkenrider ◽

Mehee Choi

Keyword(s):

Lung Cancer ◽

Clinical Application ◽

Locally Advanced ◽

Significant Risk ◽

Conformal Radiotherapy ◽

Concurrent Chemotherapy ◽

Advanced Lung Cancer ◽

3 Dimensional ◽

Contralateral Lung ◽

Locally Advanced Lung Cancer

Objective: Radiation treatment planning for locally advanced lung cancer can be technically challenging, as delivery of ≥60 Gy to large volumes with concurrent chemotherapy is often associated with significant risk of normal tissue toxicity. We clinically implemented a novel hybrid RapidArc technique in patients with lung cancer and compared these plans with 3-dimensional conformal radiotherapy and RapidArc-only plans. Materials/Methods: Hybrid RapidArc was used to treat 11 patients with locally advanced lung cancer having bulky mediastinal adenopathy. All 11 patients received concurrent chemotherapy. All underwent a 4-dimensional computed tomography planning scan. Hybrid RapidArc plans concurrently combined static (60%) and RapidArc (40%) beams. All cases were replanned using 3- to 5-field 3-dimensional conformal radiotherapy and RapidArc technique as controls. Results: Significant reductions in dose were observed in hybrid RapidArc plans compared to 3-dimensional conformal radiotherapy plans for total lung V20 and mean (−2% and −0.6 Gy); contralateral lung mean (−2.92 Gy); and esophagus V60 and mean (−16.0% and −2.2 Gy; all P < .05). Contralateral lung doses were significantly lower for hybrid RapidArc plans compared to RapidArc-only plans (all P < .05). Compared to 3-dimensional conformal radiotherapy, heart V60 and mean dose were significantly improved with hybrid RapidArc (3% vs 5%, P = .04 and 16.32 Gy vs 16.65 Gy, P = .03). However, heart V40 and V45 and maximum spinal cord dose were significantly lower with RapidArc plans compared to hybrid RapidArc plans. Conformity and homogeneity were significantly better with hybrid RapidArc plans compared to 3-dimensional conformal radiotherapy plans ( P < .05). Treatment was well tolerated, with no grade 3+ toxicities. Conclusion: To our knowledge, this is the first report on the clinical application of hybrid RapidArc in patients with locally advanced lung cancer. Hybrid RapidArc permitted safe delivery of 60 to 66 Gy to large lung tumors with concurrent chemotherapy and demonstrated advantages for reduction in low-dose lung volumes, esophageal dose, and mean heart dose.

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Concordancia entre el motivo de consulta y el diagnóstico final en pacientes pediátricos

10.24254/cnib.21.51 ◽

2021 ◽

Author(s):

◽

N. Castañeda-Villa

Keyword(s):

Medical Records ◽

Pediatric Patients ◽

Interdisciplinary Team ◽

Final Diagnosis ◽

Definitive Diagnosis ◽

Clinical Aspect ◽

Observer Agreement ◽

Medical Group ◽

Research Assistant ◽

Kappa Index

Concordance analysis using Cohen's Kappa index (􏰀􏰀) has been widely used in clinical research to determine the degree of agreement between two measurements made by the same observer (intra-observer agreement) or between the measurements of two observers on the same variable (inter- observer agreement). In this work, we used 􏰀􏰀 to determine the degree of inter-observer agreement between the reason for consultation and the final diagnosis issued by an interdisciplinary team of The Mexican Institute of Hearing and Language (IMAL). The institute receives around ten pediatric patients per month; the reasons for consulting these patients are diverse. In this research, 53 pediatric patients completed their studies in the IMAL and received a final diagnostic. A research assistant manually collected the data from the medical records of the IMAL Medical Direction. For example, 1) reason for consultation, 2) studies carried out, 3) recommendations, and 4) the final diagnosis. The global concordance between consultation and the definitive diagnosis was 􏰀􏰀 = 0.44 (moderate concordance). Although a Health Professional suggested the reason for consultation, it only covers a clinical aspect. Therefore, we think that the moderate concordance obtained is since an interdisciplinary medical group issues the final diagnostic, achieving a complete diagnosis; this allows the adequate medical care and rehabilitation of the pediatric patient.

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