\documentclass[10pt]{article}

\usepackage{fullpage}
\usepackage{setspace}
\usepackage{parskip}
\usepackage{titlesec}
\usepackage[section]{placeins}
\usepackage{xcolor}
\usepackage{breakcites}
\usepackage{lineno}
\usepackage{hyphenat}





\PassOptionsToPackage{hyphens}{url}
\usepackage[colorlinks = true,
            linkcolor = blue,
            urlcolor  = blue,
            citecolor = blue,
            anchorcolor = blue]{hyperref}
\usepackage{etoolbox}
\makeatletter
\patchcmd\@combinedblfloats{\box\@outputbox}{\unvbox\@outputbox}{}{%
  \errmessage{\noexpand\@combinedblfloats could not be patched}%
}%
\makeatother


\usepackage{natbib}




\renewenvironment{abstract}
  {{\bfseries\noindent{\abstractname}\par\nobreak}\footnotesize}
  {\bigskip}

\titlespacing{\section}{0pt}{*3}{*1}
\titlespacing{\subsection}{0pt}{*2}{*0.5}
\titlespacing{\subsubsection}{0pt}{*1.5}{0pt}


\usepackage{authblk}


\usepackage{graphicx}
\usepackage[space]{grffile}
\usepackage{latexsym}
\usepackage{textcomp}
\usepackage{longtable}
\usepackage{tabulary}
\usepackage{booktabs,array,multirow}
\usepackage{amsfonts,amsmath,amssymb}
\providecommand\citet{\cite}
\providecommand\citep{\cite}
\providecommand\citealt{\cite}
% You can conditionalize code for latexml or normal latex using this.
\newif\iflatexml\latexmlfalse
\providecommand{\tightlist}{\setlength{\itemsep}{0pt}\setlength{\parskip}{0pt}}%

\AtBeginDocument{\DeclareGraphicsExtensions{.pdf,.PDF,.eps,.EPS,.png,.PNG,.tif,.TIF,.jpg,.JPG,.jpeg,.JPEG}}

\usepackage[utf8]{inputenc}
\usepackage[english]{babel}



\usepackage{float}








\begin{document}

\title{Thrombus or Tumor ?}



\author[1]{Shiho Wakasa}%
\author[1]{Hiroya Hayashi}%
\author[1]{Takanori Yamazaki}%
\author[1]{Yasuhiro Izumiya}%
\author[1]{Daiju Fukuda}%
\affil[1]{Osaka Metropolitan University Graduate School of Medicine}%


\vspace{-1em}



  
  \date{May 27, 2024}


\begingroup
\let\center\flushleft
\let\endcenter\endflushleft
\maketitle
\endgroup








\sloppy


\textbf{Abstract}

Our patient was a 61-year-old man with dedifferentiated chondrosarcoma
(DCS) and a benign thrombus or a tumor thrombus. We diagnosed the
patient with a tumor thrombus by angioscopic observation of a
smooth-surfaced, white, elevated lesion in the IVC that had invaded the
vein wall. Although anticoagulant therapy was discontinued, his
condition progressed without an elevation in D-dimer levels or the
appearance of new thromboembolism. After one course of chemotherapy, the
patient refused to continue the treatment and was treated with
palliative care. He died of the underlying disease approximately half a
year later. This is the first case of a DCS patient where benign and
tumor thrombi was differentiated by angioscopy. Angioscopy is one of the
useful tools for this differentiation which can evaluate the color tone
and surface properties of an object.

\textbf{Main Text}

A 61-year-old Japanese man had dedifferentiated chondrosarcoma (DCS)
arising in the right femur. Preoperative contrast-enhanced computed
tomography (CT) revealed a contrast defect in the right femoral vein
(\emph{Figure A} ). We suspected that either a benign thrombus or a
tumor thrombus had developed involving the inferior vena cava (IVC) and
placed a temporary IVC filter (Neuhaus Protect, Toray Medical, Tokyo,
Japan) in the perioperative period and he underwent femoral tumor
removal. Twenty days after the operation, contrast-enhanced CT showed
extension of the contrast defect from the right popliteal vein to IVC
and new pulmonary embolic findings in the right pulmonary artery
(\emph{Figure} \emph{B, C} ). We started him on anticoagulation therapy
with rivaroxaban 15 mg/day, which did not reduce the contrast defect or
the pulmonary embolism. We placed the IVC Filter (Denali, Bard
Peripheral Vascular, Inc., Tempe, AZ) and observed the lesion with
angioscope (Visible, Intertec Medical, Tokyo, Japan). We diagnosed the
patient with a tumor thrombus by angioscopic observation of a
smooth-surfaced, white, elevated lesion in the IVC that had invaded the
vein wall (\emph{Figure D, Video} ).

Previous reports have demonstrated that FDG-PET and T2-weighted MRI can
distinguish benign and tumor thrombi \textsuperscript{12}. However,
clinically, it is not always easy to distinguish between the two.
Angioscopy facilitates these distinctions because it visually evaluates.
Our report has the potential to serve as a new diagnostic method for
tumor thrombus in the future.

\textbf{References}

1. Sharma P, Kumar R, Jeph S, et al. 2011. 18F-FDG PET-CT in the
diagnosis of tumor thrombus: can it be differentiated from benign
thrombus? \emph{Nucl Med Commun} . 32(9):782-788.

2. Yedururi S, Chawla S, Amini B, et al. 2018. Tumor thrombus in the
large veins draining primary pelvic osteosarcoma on cross sectional
imaging. \emph{Eur J Radiol} . 105:49-55.

\textbf{Legends}

\textbf{Figure.} Contrast-enhanced computed Tomography showing images
and angioscopic image of the tumor thrombus.

\begin{enumerate}
\tightlist
\item
  A contrast defect image in the right femoral vein.
\item
  A conrastt defect image in the inferior vena cava.
\item
  A new pulmonary embolism in right A10.
\item
  The surface was smooth with white solid components.
\item
  The boundary between the wall of the inferior vena cava and the tumor
  component.
\end{enumerate}

\textbf{Supplementary file.}

\textbf{Video.} Angioscopic video of the tumor thrombus.\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/CCR-figure/CCR-figure}

\end{center}
\end{figure}

\selectlanguage{english}
\FloatBarrier
\end{document}

