Journal of Medical Imaging and Radiation Oncology 58 (2014) 469–471 bs_bs_banner
R ADIOLO GY—CA SE R E P O RT
4D CT and lung cancer surgical resectability: A technical innovation John M Troupis,1,* Sundeep S Pasricha,1 Harish Narayanan,1 Frank J Rybicki2,† and Adrian W Pick3 Departments of 1Diagnostic Imaging and 3Surgery, Monash Health, Melbourne, Victoria, Australia, and 2Applied Imaging Sciences Laboratory, Brigham & Women’s Hospital, Boston, Massachusetts, USA
JM Troupis MBBS, FRANZCR; SS Pasricha MBBS, FRANZCR, MMed; H Narayanan MBBS, MD, FRANZCR; FJ Rybicki MD, PhD; AW Pick MBBS, FRACS. Correspondence A/Professor John M Troupis, Department of Diagnostic Imaging, Monash Health, 246 Clayton Road, Clayton, Melbourne, Vic. 3168, Australia. Email: [email protected]
Summary A 74-year-old man presents with a left upper lobe lung adenocarcinoma, which demonstrated a wide base intimately with the aortic arch. We utilised 4D CT technique with a wide field of view CT unit to preoperatively determine likely surgical resectability. We propose that 4D CT may be of use in further investigating lung cancer with likely invasion of adjacent structures. Key words: body CT; chest imaging; respiratory.
Conflict of interest: None. *Present address: Department of Medical Imaging and Radiation Sciences, Faculty of Medicine, Dentistry and Nursing, Monash University, Wellington Rd. Clayton, Vic 3800, Australia. †
Present address: Applied Imaging Sciences Laboratory, Brigham and Women’s Hospital, Department of Radiology, RA024, 75 Francis Street, Boston, MA 02115, USA. Submitted 1 October 2013; accepted 18 December 2013. doi:10.1111/1754-9485.12161
Introduction A 74-year-old man presents with biopsy-proven 4.5 cm left upper lobe adenocarcinoma with no evidence of avidity on positron emission tomography elsewhere. Staging CT (Figs 1,2) demonstrates the mass located in intimate apposition with the distal aortic arch without a definite plane between the mass and the aorta. As invasion of the aortic arch could not be excluded, the mass was staged as T4N0M0.1 In view of the close apposition, and difficulty in determining resectability, with appropriate patient informed consent, a wide field of view 4D CT using 320-slice multi detector computer tomography (Aquilion ONE, Toshiba © 2014 The Royal Australian and New Zealand College of Radiologists
Medical Systems, Tochigi, Japan) was performed with superior–inferior (Z axis) coverage of 16 cm and tube rotation 0.375 seconds2–4 while the patient inspired and expired. Several pre-scanning practice respirations were undertaken so that the patient was able to achieve full inspiration to full expiration and back within approximately 2 seconds. Once the patient demonstrated an ability to successfully complete two cycles in the required time frame, the CT acquisition was activated. Total dose length product was 565 mGy × cm, which is equivalent to 7.9 mSv (conversion factor of 0.014). Twenty phases were acquired over approximately 4 seconds. Each phase corresponds with a single volume acquisition. As such, post-processing of images involves 469
JM Troupis et al.
Fig. 3. Arrow highlights most inferior extent of mass in maximum inspiration.
Fig. 1. Axial post contrast image of the left upper lobe biopsy proven carcinoma demonstrating wide base intimately related to the distal aortic arch.
the ability to produce cine movies in any plane and in any format, including multiplanar reformat images and volume-rendered images. The data set was then examined in numerous planes to identify the plane that best demonstrates the pres-
ence or absence of differential motion of the mass in relation to the adjacent aorta. Figures 3–5 demonstrate the maximum inspiration, mid-respiratory cycle and maximum expiration views in the oblique coronal plane, which highlight the mass motion in relation to the aortic intimal calcification. Supporting Information Video Clip S1 best demonstrates the motion of the mass in relation to the distal aortic arch. We postulate that the presence of differential motion confirms the absence of ‘tethering’ of the mass to the adjacent structure with likely adherence to the visceral pleura and without involvement of the parietal pleura. Differential motion would therefore suggest that surgical resectability is possible without either significant compli-
Fig. 4. Arrow highlights position of the mass in the mid-section of the respiratory cycle.
Fig. 2. Coronal post contrast image of the left upper lobe biopsy proven carcinoma demonstrates the wide base of the lesion intimately related to the distal aortic arch.
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Fig. 5. Arrow highlights the most superior position of the mass in maximum expiration. © 2014 The Royal Australian and New Zealand College of Radiologists
4D CT and lung cancer resectability
cation or the need to plan for extensive surgery. Based on 4D CT, and likely absence of aortic invasion, the presurgical stage was amended to T2aN0M0. A left upper lobectomy was performed without complication and without requirement for surgical dissection from the aorta. Histopathology of resected specimen confirms absence of invasion of parietal pleural surface. It has been previously shown that respiratory dynamic MRI may assist in determination of differential motion and therefore operability,5 with key advantage of lack of ionising radiation. By using 4D CT, we note that key differences from respiratory dynamic MRI include the acquisition of a volume data set with ability to evaluate differential motion in numerous planes.
Conclusion Utilising 4D CT (cine CT), we utilised the absence of differential motion of a lung carcinoma in relation to the adjacent aorta to indicate that the mass was likely surgically resectable. 4D CT is an emerging technique that may add significant preoperative information. Further large scale prospective studies would be of use to assess the relative value in provision of preoperative information in relation to the position of the mass and the subtypes of carcinoma.
2.
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staging system and potential imaging pitfalls. Radiographics 2010; 30: 1163–81. Ohtsuka T, Minami M, Nakajima J, Kohno T, Yagyu K, Furuse A. Cine computed tomography for evaluation of tumors invasive to the thoracic aorta: seven clinical experiences. J Thorac Cardiovasc Surg 1996; 112: 190–2. Troupis JM, Amis B. Four-dimensional computed tomography and trigger lunate syndrome. J Comput Assist Tomogr 2013; 37: 639–43. Underberg RW, Lagerwaard FJ, Cuijpers JP, Slotman BJ, van Sornsen de Koste JR, Senan S. Four-dimensional CT scans for treatment planning in stereotactic radiotherapy for stage I lung cancer. Int J Radiat Oncol Biol Phys 2004; 60: 1283–90. Akata S, Kajiwara N, Park J et al. Evaluation of chest wall invasion by lung cancer using respiratory dynamic MRI. J Med Imaging Radiat Oncol 2008; 52: 36–9.
Supporting Information Additional Supporting Information may be found in the online version of this article at the publisher’s web-site: Video Clip S1. Oblique coronal multiplanar reformatted cine during full inspiration to expiration confirming differential motion between the para aortic left upper lobe mass and the adjacent distal aortic arch.
References 1. UyBico SJ, Wu CC, Suh RD, Le NH, Brown K, Krishnam MS. Lung cancer staging essentials: the new TNM
© 2014 The Royal Australian and New Zealand College of Radiologists
471
R ADIOLO GY—CA SE R E P O RT
4D CT and lung cancer surgical resectability: A technical innovation John M Troupis,1,* Sundeep S Pasricha,1 Harish Narayanan,1 Frank J Rybicki2,† and Adrian W Pick3 Departments of 1Diagnostic Imaging and 3Surgery, Monash Health, Melbourne, Victoria, Australia, and 2Applied Imaging Sciences Laboratory, Brigham & Women’s Hospital, Boston, Massachusetts, USA
JM Troupis MBBS, FRANZCR; SS Pasricha MBBS, FRANZCR, MMed; H Narayanan MBBS, MD, FRANZCR; FJ Rybicki MD, PhD; AW Pick MBBS, FRACS. Correspondence A/Professor John M Troupis, Department of Diagnostic Imaging, Monash Health, 246 Clayton Road, Clayton, Melbourne, Vic. 3168, Australia. Email: [email protected]
Summary A 74-year-old man presents with a left upper lobe lung adenocarcinoma, which demonstrated a wide base intimately with the aortic arch. We utilised 4D CT technique with a wide field of view CT unit to preoperatively determine likely surgical resectability. We propose that 4D CT may be of use in further investigating lung cancer with likely invasion of adjacent structures. Key words: body CT; chest imaging; respiratory.
Conflict of interest: None. *Present address: Department of Medical Imaging and Radiation Sciences, Faculty of Medicine, Dentistry and Nursing, Monash University, Wellington Rd. Clayton, Vic 3800, Australia. †
Present address: Applied Imaging Sciences Laboratory, Brigham and Women’s Hospital, Department of Radiology, RA024, 75 Francis Street, Boston, MA 02115, USA. Submitted 1 October 2013; accepted 18 December 2013. doi:10.1111/1754-9485.12161
Introduction A 74-year-old man presents with biopsy-proven 4.5 cm left upper lobe adenocarcinoma with no evidence of avidity on positron emission tomography elsewhere. Staging CT (Figs 1,2) demonstrates the mass located in intimate apposition with the distal aortic arch without a definite plane between the mass and the aorta. As invasion of the aortic arch could not be excluded, the mass was staged as T4N0M0.1 In view of the close apposition, and difficulty in determining resectability, with appropriate patient informed consent, a wide field of view 4D CT using 320-slice multi detector computer tomography (Aquilion ONE, Toshiba © 2014 The Royal Australian and New Zealand College of Radiologists
Medical Systems, Tochigi, Japan) was performed with superior–inferior (Z axis) coverage of 16 cm and tube rotation 0.375 seconds2–4 while the patient inspired and expired. Several pre-scanning practice respirations were undertaken so that the patient was able to achieve full inspiration to full expiration and back within approximately 2 seconds. Once the patient demonstrated an ability to successfully complete two cycles in the required time frame, the CT acquisition was activated. Total dose length product was 565 mGy × cm, which is equivalent to 7.9 mSv (conversion factor of 0.014). Twenty phases were acquired over approximately 4 seconds. Each phase corresponds with a single volume acquisition. As such, post-processing of images involves 469
JM Troupis et al.
Fig. 3. Arrow highlights most inferior extent of mass in maximum inspiration.
Fig. 1. Axial post contrast image of the left upper lobe biopsy proven carcinoma demonstrating wide base intimately related to the distal aortic arch.
the ability to produce cine movies in any plane and in any format, including multiplanar reformat images and volume-rendered images. The data set was then examined in numerous planes to identify the plane that best demonstrates the pres-
ence or absence of differential motion of the mass in relation to the adjacent aorta. Figures 3–5 demonstrate the maximum inspiration, mid-respiratory cycle and maximum expiration views in the oblique coronal plane, which highlight the mass motion in relation to the aortic intimal calcification. Supporting Information Video Clip S1 best demonstrates the motion of the mass in relation to the distal aortic arch. We postulate that the presence of differential motion confirms the absence of ‘tethering’ of the mass to the adjacent structure with likely adherence to the visceral pleura and without involvement of the parietal pleura. Differential motion would therefore suggest that surgical resectability is possible without either significant compli-
Fig. 4. Arrow highlights position of the mass in the mid-section of the respiratory cycle.
Fig. 2. Coronal post contrast image of the left upper lobe biopsy proven carcinoma demonstrates the wide base of the lesion intimately related to the distal aortic arch.
470
Fig. 5. Arrow highlights the most superior position of the mass in maximum expiration. © 2014 The Royal Australian and New Zealand College of Radiologists
4D CT and lung cancer resectability
cation or the need to plan for extensive surgery. Based on 4D CT, and likely absence of aortic invasion, the presurgical stage was amended to T2aN0M0. A left upper lobectomy was performed without complication and without requirement for surgical dissection from the aorta. Histopathology of resected specimen confirms absence of invasion of parietal pleural surface. It has been previously shown that respiratory dynamic MRI may assist in determination of differential motion and therefore operability,5 with key advantage of lack of ionising radiation. By using 4D CT, we note that key differences from respiratory dynamic MRI include the acquisition of a volume data set with ability to evaluate differential motion in numerous planes.
Conclusion Utilising 4D CT (cine CT), we utilised the absence of differential motion of a lung carcinoma in relation to the adjacent aorta to indicate that the mass was likely surgically resectable. 4D CT is an emerging technique that may add significant preoperative information. Further large scale prospective studies would be of use to assess the relative value in provision of preoperative information in relation to the position of the mass and the subtypes of carcinoma.
2.
3.
4.
5.
staging system and potential imaging pitfalls. Radiographics 2010; 30: 1163–81. Ohtsuka T, Minami M, Nakajima J, Kohno T, Yagyu K, Furuse A. Cine computed tomography for evaluation of tumors invasive to the thoracic aorta: seven clinical experiences. J Thorac Cardiovasc Surg 1996; 112: 190–2. Troupis JM, Amis B. Four-dimensional computed tomography and trigger lunate syndrome. J Comput Assist Tomogr 2013; 37: 639–43. Underberg RW, Lagerwaard FJ, Cuijpers JP, Slotman BJ, van Sornsen de Koste JR, Senan S. Four-dimensional CT scans for treatment planning in stereotactic radiotherapy for stage I lung cancer. Int J Radiat Oncol Biol Phys 2004; 60: 1283–90. Akata S, Kajiwara N, Park J et al. Evaluation of chest wall invasion by lung cancer using respiratory dynamic MRI. J Med Imaging Radiat Oncol 2008; 52: 36–9.
Supporting Information Additional Supporting Information may be found in the online version of this article at the publisher’s web-site: Video Clip S1. Oblique coronal multiplanar reformatted cine during full inspiration to expiration confirming differential motion between the para aortic left upper lobe mass and the adjacent distal aortic arch.
References 1. UyBico SJ, Wu CC, Suh RD, Le NH, Brown K, Krishnam MS. Lung cancer staging essentials: the new TNM
© 2014 The Royal Australian and New Zealand College of Radiologists
471
