Correlation of segmented metabolic tumor volume with outcome--letter.

نویسندگان

  • Esther G C Troost
  • Dominic A X Schinagl
  • Johan Bussink
  • Johannes H A M Kaanders
  • Wim J G Oyen
  • Otto C Boerman
چکیده

Comment on Chung et al. “Metabolic tumor volume of [F]-fluorodeoxyglucose positron emission tomography/ computed tomography predicts short-term outcome to radiotherapy with or without chemotherapy in pharyngeal cancer” published in Clinical Cancer Research 2009;15 (18):5861-5866. With great interest, we read the publication by Chung et al. (1). In 82 pharyngeal cancer patients undergoing (chemo)radiation, the authors studied the prognostic value of a “metabolic tumor volume” (MTV), defined as increased FDG-PET uptake in primary tumors and lymph node metastases. Although this concept seems appealing, we feel that comments about the methods are justified. First, the authors chose a threshold of 2.5 for the standardized uptake value (SUV) for segmentation of the FDG-PET images, which is commonly applied in NSCLC. Not only is this threshold arbitrary and protocol dependent (2), but the most appropriate threshold for FDG-PET segmentation in head and neck tumors remains to be determined. As opposed to NSCLC, head and neck tumors are surrounded by closely packed tissue consisting of squamous cells, the cell type the tumor originated from, and peritumoral inflammation hampering PET segmentation. In two recent publications, we showed the effect of applying different thresholds, including SUV 2.5, on the segmentation of primary head and neck tumors and cervical lymph nodes and advocated the validation of iterative methods (3, 4). Furthermore, as shown by Nagakawa et al. (5), a threshold of SUV 2.5 is ineffective for the segmentation of metastatic lymph nodes, as 30% of patients had reactive cervical lymph nodes with a maximum SUV of 2.5 or higher. Second, the authors did not incorporate necrotic areas within the tumor or lymph nodes in the MTVs because they do not consume FDG. However, necrotic volumes are often the result of severe hypoxia, a tumor characteristic adversely affecting treatment outcome and prognosis. Thus, although this approach may be legitimate in terms of defining the MTV, these patients should be either excluded from the analysis or analyzed as separate cohort because this confounding characteristic may also influence the correlation of MTVs with short-term outcome. Third and most importantly, Chung et al. omitted to correlate the gross tumor volumes (GTV) on CT with the MTVs and short-term treatment outcomes in both univariate and multivariate analyses. There is solid evidence that the GTV of the primary tumor and metastatic cervical lymph nodes is one of the most powerful prognostic fac-

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Evaluation of methods of co-segmentation on PET/CT images of lung tumor: simulation study

Introduction: Lung cancer is one of the most common causes of cancer-related deaths worldwide. Nowadays PET/CT plays an essential role in radiotherapy planning specially for lung tumors as it provides anatomical and functional information simultaneously that is effective in accurate tumor delineation. The optimal segmentation method has not been introduced yet, however several ...

متن کامل

Comparison of novel multi-level Otsu (MO-PET) and conventional PET segmentation methods for measuring FDG metabolic tumor volume in patients with soft tissue sarcoma

BACKGROUND We have previously developed a novel and highly consistent PET segmentation algorithm using a multi-level Otsu method (MO-PET). The aim of this study was to evaluate the reliability of MO-PET compared to conventional PET segmentation methods for measuring 18F-FDG (FDG) PET metabolic tumor volume (MTV) in patients with soft tissue sarcoma (STS). Clinical and imaging data were obtained...

متن کامل

Correlation of Leukocyte Count and Percentage of Segmented Neutrophils with Pathohistological Findings of Appendix in Children

BackgroundAppendicitis is the most common indication for an emergency operation in children's age. Although none of the laboratory values has not high sensitivity and specificity for the diagnosis of appendicitis, leukocyte count and the percentage of segmented neutrophils are most commonly used. The aim of this study was to determine whether there is a statistically significant correlation bet...

متن کامل

Optimum Contouring Method for Metabolic Tumor Volume Using PET/CT in Patients with Oral Cavity Squamous Cell Carcinoma

The metabolic tumor volume (MTV) is the volume of metabolically-active tumor on PET/CT. Although its potential clinical value has been investigated in many cancers, its routine use has been hampered by the delineation method used to calculate the tumor volume. This may be especially difficult for fuzzyPET images. Previous studies have used a lot of approaches for delineation of tumor volume; ho...

متن کامل

Using Bayesian tissue classification to improve the accuracy of vestibular schwannoma volume and growth measurement.

BACKGROUND AND PURPOSE True 3D measurements of tumor volume are time-consuming and subject to errors that are particularly pronounced in cases of small tumors. These problems complicate the routine clinical assessment of tumor growth rates. We examined the accuracy of currently available methods of size and growth measurement of vestibular schwannomas compared with that of a novel fast partial ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:
  • Clinical cancer research : an official journal of the American Association for Cancer Research

دوره 16 6  شماره 

صفحات  -

تاریخ انتشار 2010