January 30, 2011 (Phoenix, Arizona) — Computed tomography (CT) is not a reliable predictor of cartilage invasion in advanced laryngeal carcinoma, according to research presented here at the 2012 Multidisciplinary Head and Neck Cancer Symposium (MHNCS).
Under the current standard of care, patients with locally advanced laryngeal cancer who have CT evidence of invasion through the thyroid or cricoid cartilage are treated with laryngectomy rather than organ-preserving therapy. However, data demonstrating the accuracy of CT in making the distinction have been weak, according to coauthor Peter Paximadis, MD, from Wayne State University in Detroit, Michigan.
"We sought to review our institutional data correlating radiographic findings with actual pathologic results," he told Medscape Medical News.
For the study, the researchers evaluated 92 patients treated from 1999 to 2009, including 87 who were treated for clinically staged T3 to T4 laryngeal carcinoma and 5 treated for T4 hypopharyngeal squamous cell carcinoma. All of the patients received preoperative CT of the neck not more than 4 weeks before the total laryngectomy.
According to the CT results, 37 of the 92 patients had evidence of cartilage invasion.
The investigators reported that subsequent pathologic reviews showed that 15 of the 37 patients (41%) did not have any actual cartilage invasion, yielding a positive predictive value (PPV) of 59% (95% confidence interval [CI], 43 to 74).
The findings resulted in a negative predictive value (NPV) of 85% (95% CI, 74 to 93). Sensitivity was 73% (95% CI, 56 to 86) and specificity was 76% (95% CI. 64 to 85).
When the researchers considered only the more specific radiographic finding of invasion through cartilage, they found a PPV of 61% (95% CI, 41 to 78).
NPV was 77% (95% CI, 66 to 85), sensitivity was 47% (95% CI, 30 to 64), and specificity was 85% (95% CI, 76 to 92).
"We had a suspicion that the reliability of CT would be poor, but it was still somewhat surprising to see the remarkable lack of accuracy, specifically when looking at the rate of false positives," Dr. Paximadis said.
The results are troubling, considering the consequences, he added.
"For these patients, a false positive would have likely resulted in a recommendation for laryngectomy when an organ-preserving approach could have possibly been a viable option."
Dr. Paximadis said that he and his colleagues are currently investigating whether cartilage invasion is actually correlated with poorer outcomes in patients who are treated with an organ-preserving approach.
In the meantime, "we feel that the results of this study should lead one to be cautious making treatment recommendations based solely on the radiographic finding of cartilage invasion," he said.
In presenting the findings here at the MHNCS, coauthor Michael Dominello, DO, also from Wayne State University, was asked by an audience member if magnetic resonance imaging (MRI) represents an appropriate alternative to CT.
Dr. Dominello responded that a review of recent literature shows MRI accuracy sensitivities ranging from the 80s to low 90s, and specificity from the mid-70s to the mid 80s.
"Both CT and MRI are acceptable modalities in the staging of the neck; however, the potential caveat is an interpreter's comfort with an MRI modality," he said.
Joseph Rajendran, MD, professor of radiology and radiation oncology in the division of nuclear medicine at the University of Washington in Seattle, said he believes that, considering concerns of CT-related inflammation leading to inaccurate readings, the concerns are valid.
"CT has been used extensively in these situations, but it has its drawbacks," he said. "The problem with CT or PET/CT is the secondary reaction in the cartilage and any inflammation that goes on."
"CT produces a lot of edema in the neighborhood, and cartilage is very notorious for that," Dr. Rajendran explained. "Other factors could include the presence of infection and other reactions to the primary tumor."
"People should always be aware of that and, when selecting cases, they should go by the size of the tumor, the histology, and other findings related to that."
The authors have disclosed no relevant financial relationships.
2012 Multidisciplinary Head and Neck Cancer Symposium (MHNCS): Abstract 11. Presented January 27
Under the current standard of care, patients with locally advanced laryngeal cancer who have CT evidence of invasion through the thyroid or cricoid cartilage are treated with laryngectomy rather than organ-preserving therapy. However, data demonstrating the accuracy of CT in making the distinction have been weak, according to coauthor Peter Paximadis, MD, from Wayne State University in Detroit, Michigan.
"We sought to review our institutional data correlating radiographic findings with actual pathologic results," he told Medscape Medical News.
For the study, the researchers evaluated 92 patients treated from 1999 to 2009, including 87 who were treated for clinically staged T3 to T4 laryngeal carcinoma and 5 treated for T4 hypopharyngeal squamous cell carcinoma. All of the patients received preoperative CT of the neck not more than 4 weeks before the total laryngectomy.
According to the CT results, 37 of the 92 patients had evidence of cartilage invasion.
The investigators reported that subsequent pathologic reviews showed that 15 of the 37 patients (41%) did not have any actual cartilage invasion, yielding a positive predictive value (PPV) of 59% (95% confidence interval [CI], 43 to 74).
The findings resulted in a negative predictive value (NPV) of 85% (95% CI, 74 to 93). Sensitivity was 73% (95% CI, 56 to 86) and specificity was 76% (95% CI. 64 to 85).
When the researchers considered only the more specific radiographic finding of invasion through cartilage, they found a PPV of 61% (95% CI, 41 to 78).
NPV was 77% (95% CI, 66 to 85), sensitivity was 47% (95% CI, 30 to 64), and specificity was 85% (95% CI, 76 to 92).
"We had a suspicion that the reliability of CT would be poor, but it was still somewhat surprising to see the remarkable lack of accuracy, specifically when looking at the rate of false positives," Dr. Paximadis said.
The results are troubling, considering the consequences, he added.
"For these patients, a false positive would have likely resulted in a recommendation for laryngectomy when an organ-preserving approach could have possibly been a viable option."
Dr. Paximadis said that he and his colleagues are currently investigating whether cartilage invasion is actually correlated with poorer outcomes in patients who are treated with an organ-preserving approach.
In the meantime, "we feel that the results of this study should lead one to be cautious making treatment recommendations based solely on the radiographic finding of cartilage invasion," he said.
In presenting the findings here at the MHNCS, coauthor Michael Dominello, DO, also from Wayne State University, was asked by an audience member if magnetic resonance imaging (MRI) represents an appropriate alternative to CT.
Dr. Dominello responded that a review of recent literature shows MRI accuracy sensitivities ranging from the 80s to low 90s, and specificity from the mid-70s to the mid 80s.
"Both CT and MRI are acceptable modalities in the staging of the neck; however, the potential caveat is an interpreter's comfort with an MRI modality," he said.
Joseph Rajendran, MD, professor of radiology and radiation oncology in the division of nuclear medicine at the University of Washington in Seattle, said he believes that, considering concerns of CT-related inflammation leading to inaccurate readings, the concerns are valid.
"CT has been used extensively in these situations, but it has its drawbacks," he said. "The problem with CT or PET/CT is the secondary reaction in the cartilage and any inflammation that goes on."
"CT produces a lot of edema in the neighborhood, and cartilage is very notorious for that," Dr. Rajendran explained. "Other factors could include the presence of infection and other reactions to the primary tumor."
"People should always be aware of that and, when selecting cases, they should go by the size of the tumor, the histology, and other findings related to that."
The authors have disclosed no relevant financial relationships.
2012 Multidisciplinary Head and Neck Cancer Symposium (MHNCS): Abstract 11. Presented January 27
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