MULTIMEDIA MANUAL OF
doi:10.1093/mmcts/mmu025 published online 12 December 2014.
MMCTS
CARDIO-THORACIC SURGERY
Total thoracoscopic posterior basal segmentectomy for primary lung cancer Wataru Nishio*, Kenta Tane, Kazuya Uchino and Masahiro Yoshimura Department of Chest Surgery, Hyogo Cancer Center, Akashi, Japan *Corresponding author. Department of Chest Surgery, Hyogo Cancer Center, 13-70 Kitaoji-cho, Akashi, Japan. Tel: +81-78-9291151; fax: +81-78-9292380; e-mail: [email protected] (W. Nishio). Received 12 August 2014; revised 9 October 2014; accepted 12 November 2014
Summary This report introduces a hilar side approach for posterior basal segmentectomies by the process of specific vision thoracoscopic surgery, which has been used extensively for peripheral small lung cancer by the author. Although it requires a deeper understanding of hilar anatomy and fine control, it is safer and less invasive to the thoracic wall and results in less postoperative pain than the thoracotomy counterpart and as a hilar side approach allows for less deformation. The necessary order of processes involves specific vision, inflation– deflation and blunt dissection from the hilum. Keywords: Thoracoscopy • Segmentectomy • Lung cancer
INTRODUCTION Although it has restricted accessibility and operability relative to thoracotomies, total thoracoscopic surgery (TS) is a reasonable approach for limited lung resection due to being less invasive to the thoracic wall and resulting in relatively less postoperative pain. Furthermore, TS is a common procedure for lobectomies [1]. As operative skills and devices improve, TS is increasingly being used for segmentectomies [2, 3]. The author has performed multiple segmentectomies for lung cancer using mini-thoracotomies, but now exclusively uses TS [4]. In the case of primary lung cancer, there are metastases along the lymphatic system [5]. Consequently, anatomical segmentectomy is preferential by generally first identifying all segmental veins in the hilum, severing the pulmonary artery(ies), veins and the bronchus, and then excising the lung parenchyma from the hilum to the periphery along the intersegmental veins. This does not apply to posterior basal segmentectomies (S10 segmentectomies) as the basal segmental veins do not diverge widely or consistently, and it is difficult to identify them at the hilum. Furthermore, it is difficult to secure B10 and A10 without first separating the lung parenchyma as their diverging points are situated deeply. For these reasons, S10 segmentectomies tend to be avoided even with thoracotomies, let alone with TS. This report introduces a relatively simpler hilar side approach for S10 segmentectomies by the process of a specific perspective TS.
identified with relatively high confidence. The most apparent indication to perform a segmentectomy is if the lung cancer is radiologically non-invasive (consolidation to a tumour ratio of 0.5 or less in clinical T1a-b) and if wedge resection cannot ensure the resectional margin due to the depth of the cancer, and for radiologically invasive cancer (consolidation to a tumour ratio of greater than 0.5 in clinical T1a) segmentectomies are performed when the case is assigned to the segmentectomy group of the JCOG 0802 trial [6, 7]. The trial, however, is not appropriate for respiratory comorbid patients suffering from chronic obstructive pulmonary disease, for patients who have received a lung resection or for patients who have multiple ground glass opacities. In these cases, segmentectomy is advocated.
Preparation The distribution of the bronchi and pulmonary vessels is identified with a three-dimensional CT reconstruction. The basal bronchus generally diverges into B8 and B9 + 10. Notice must be taken of the sub-superior segmental branch (B*), or B10a, as it may need to be severed prior to securing B10 (Fig. 1). If the tumour is situated near the segmental border and it is expected to not be properly identified thoracoscopically, then CT-guided needle marking is preferred preoperatively.
Strategy of four-port VATS SURGICAL TECHNIQUE Patient selection Thin-slice CT results are the primary criteria in determining the procedure to be used as the malignancy of a tumour can be
The author performs every lobectomy and segmentectomy procedure with four ports to ensure control comparable with open thoracic surgery (see Fig. 2 for port location). All ports are wrapped with Lap Protector (Hakko Co. Ltd, Nagano, Japan) silicone sleeves both to protect from contamination and to facilitate changing devices.
© The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
W. Nishio et al. / Multimedia Manual of Cardio-Thoracic Surgery
A rigid 30° diagonal vision thoracoscope is used and inserted through the most appropriate caudal port to allow the visual axis to align with the major fissure. The two devices used by the operator are inserted independently from the two ports and they sandwich the thoracoscope (coaxial approach and triangle formation). An assistant provides the operative field and adds counter-traction by crossing the two devices from the fourth port (Fig. 3). Commonly used instruments are shown in Fig. 4. In segmentectomies, when dissecting along the intersegmental plane from the
2
hilum, many small veins that flow into intersegmental veins should be severed. Ultrasonic shears (Harmonic Ace, Ethicon, NJ, USA) are preferred as they can simultaneously seal and sever small vessels, reducing operation time.
Separating B6 and the basal bronchus The first port is routinely made on the anterior mid-axillar line in the seventh intercostal space for lower lobe lobectomies and segmentectomies. After confirming the status of the thoracic cavity by thoracoscope, interlobar manipulation is then performed. Unless there is incomplete lobulation, the basal segmental artery on the interlobar plane is secured and retracted. Behind the artery, the bifurcation of B6 as well as the basal bronchus is exposed.
Isolating S10 from S6 After turning the lower lobe anteriorly, the mediastinal pleura is incised. A distal dissection is made along V6b and V6c. The lateral wall of the basal bronchus and artery are identified and repositioned downwards from the lung parenchyma, allowing access to the interlobar plane. Dissecting forceps are inserted posteriorly towards the bifurcation of B6 and the basal bronchus on the interlobar plane. A silicone drain is passed along this route as a directional guide. S10 is isolated from S6 by mechanical stapling (Video 1). Tunnelling under the parenchyma reduces risk to the pulmonary arteries by distancing them. Repositioning the parenchyma allows the surgical margin with relative ease. If the cancer in S10 were near the S6 border, the dissection line would be into S6. However, if the cancer were in S10 along the S9 border, the dissection would be set between S6 and S9 and the operative method would have been converted to an S9 + S10 bisegmentectomy (Fig. 5).
Inflation–deflation Figure 1: B9 and B10 diverge in the centre of the lower lobe. B* or B10a diverges to the rear acting as a barrier.
B* (or B10a) is severed at this time. B10 is secured and the anaesthesiologist advances the bronchoscope through B10 to perform
Figure 2: All ports are covered with silicone sleeves. In upper or middle lobectomies or segmentectomies, all ports are shifted up one intercostal space.
3
W. Nishio et al. / Multimedia Manual of Cardio-Thoracic Surgery
Figure 3: In our four-port strategy for posterior basal segmentectomy, the operator stands on the back side, as opposed to the standard ventral side, because most hilar manipulations are more easily performed from the back.
Figure 4: Preference card: 1. Rigid 30° diagonal view scope; 2. Cotton ball (Thoraco Cotton, Kenzmedico Co. Ltd, Saitama, Japan); 3. Grasping forceps for TS, fine DeBakey; 4. Dissecting forceps for TS, fine Maryland; 5. Suction, pencil-shaped; 6. Waldfuss tear drop forceps; 7. Surgical stapler (Endo GIA 45 mm Purple and Black Reload, Covidien, MA, USA). When the assistant provides the operative field, it is preferred to use cotton balls as it is non-invasive to the lung parenchyma and adding countertraction by crossing two cotton balls expedites pleural dissection.
jet ventilation on S10. B10 and A10 are severed. V10 is severed as it runs inside S10. Retracting the distal B10 stump allows for clear identification of V6, V8 and V9 (Video 2).
Video 1: S10 is isolated from S6 by tunnelling under the intersegmental plane, and identifying the basal segmental arteries, veins and bronchus. A thoracoscopic magnified and upward view is used. The inflation–deflation method is not required.
bronchioles are found, they should be sutured. In most cases, the amount of air leakage is low (Video 4). A fibrin sealant is applied to the raw surfaces of the remaining lung to prevent air leakage after electrocautery.
RESULTS
Completing the resection S10 is bluntly isolated from S9 along V9a and V9b from the hilum using the demarcation line as a reference. While performing these procedures in the hilum, the demarcation line will have emerged clearly on the lung’s surface. Electrocautery is used to dissect along the demarcation line until mechanical stapling becomes viable, avoiding postoperative fistula of the bronchioles (Video 3).
Wrapping up The subcarinal lymph nodes are dissected similarly to a lower lobectomy. The air-leak test is performed and if fistulae of the
Four cases of total thoracoscopic segmentectomies were performed as detailed above from February 2013 to May 2014 on two right S10, one left S10 and one left S9 + S10 segments. All cases had not had pathological diagnoses preoperatively, but had been highly suspected of having lung cancer with radiological findings by thin-slice CT. No blood transfusions were required. One patient suffered from atrial fibrillation postoperatively, and medication was sufficient to recover sinus rhythm. All patients were diagnosed with primary lung cancer (adenocarcinoma) postoperatively. No hilar lymph node involvement was observed. Two tumours were pathologically graded as T1aN0 and the other two as T2aN0 due
4
W. Nishio et al. / Multimedia Manual of Cardio-Thoracic Surgery
Figure 5: B9 + 10 and A9 + 10 are clearly visible after severing along V6b and V6c. Video 3: Resection of S10 from S9 in three steps.
Video 4: Post-resectional view and minimal air leakage. Video 2: Manipulating the hilar structures; inflation–deflation method.
to p2a factor. No tumour recurrence has been noted in follow-ups (Table 1).
DISCUSSION Segmentectomy or lobectomy Segmentectomies for primary lung cancer are often thought of as being more limited and as sacrificing prognosis to preserve pulmonary functions. Some retrospective studies, however, have shown that prognosis with clinical T1a lung cancer is equal to that of standard lobectomies for carefully selected patients [8–10]. As improving diagnostics increase the likelihood of detecting small lung cancer, and redo operations become frequent with increasing life span, so does the requirement and desire for segmentectomies.
Issues with posterior basal segmentectomy In S10 segmentectomies, it is difficult to secure B10 without incising the lung parenchyma and to sever S10 from S9 by only
Table 1: Surgical results Variable Operative time (min) Range Median Bleeding (g) Range Median Chest tube duration (days) Range Median Complication Atrial fibrillation Pathological diagnoses Adenocarcinoma T1aN0 T2aN0
No. of patients (n = 4) 147–269 219 20–160 90 2–4 2 1 2 2
dissecting along the intersegmental veins. This first issue is solved by first dissection of S6 and S10 as mentioned above. The inflation–deflation method is helpful to identify the intersegmental plane between S9 and S10, particularly in peripheral
5
W. Nishio et al. / Multimedia Manual of Cardio-Thoracic Surgery
lesions [11]. This requires an anaesthesiologist, but it is convenient and without complications, that is, cerebral air embolism. The demarcation line emerges clearly between the basal segments as the lower lobe suffers relatively less from emphysema. Mechanical stapling is suitable for severing the segmental bronchus; if it were only severed by ligation, the thread would very likely slip off and the segment would deflate.
Tips for hilar side dissection For operators unfamiliar with segmentectomies, the beginning of hilar side dissection seems to be the most difficult part. Converging segments are narrow near the hilum and demarcation lines do not clearly emerge. This is solved by first retracting the B10 stump and bluntly dissecting to expose the side wall of B9. Once the hilar part of S10 is held up after retracting the B10 stump, the small veins between the intersegmental vein and the resectional segment are exposed. As the small veins are severed from the hilum to the periphery, the parenchyma can gradually be bluntly dissected exposing more small veins along the way, reducing deformation and minimizing sharp dissection from the surface.
Surface dissection Two important technical points should be considered when dissecting from the surface: first, adding significant counter-traction to the resectional plane while excising along the demarcation line by electrocautery on low output. Second, performing the incision at uniform depth along the same path several times to avoid deviating from the correct intersegmental plane, which would cause prolonged postoperative air leakage. Conflict of interest: none declared.
REFERENCES [1] Nicastri DG, Wisnivesky JP, Litle VR, Yun J, Chin C, Dembitzer FR et al. Thoracoscopic lobectomy: report on safety, discharge independence, pain, and chemotherapy tolerance. J Thorac Cardiovasc Surg 2008;135:642–7. [2] Shapiro M, Weiser TS, Wisnivesky JP, Chin C, Arustamyan M, Swanson SJ. Thoracoscopic segmentectomy compares favorably with thoracoscopic lobectomy for patients with small stage I lung cancer. J Thorac Cardiovasc Surg 2009;137:1388–93. [3] Oizumi H, Kanauchi N, Kato H, Endoh M, Suzuki J, Fukaya K et al. Anatomic thoracoscopic pulmonary segmentectomy under 3-dimensional multidetector computed tomography simulation: a report of 52 consecutive cases. J Thorac Cardiovasc Surg 2011;141:678–82. [4] Okada M, Nishio W, Sakamoto T, Uchino K, Yuki T, Nakagawa A et al. Effect of tumor size on prognosis in patients with non-small cell lung cancer: the role of segmentectomy as a type of lesser resection. J Thorac Cardiovasc Surg 2005;129:87–93. [5] Sakairi Y, Yoshino I, Yoshida S, Suzuki H, Tagawa T, Iwata T et al. Pattern of metastasis outside tumor-bearing segments in primary lung cancer: rationale for segmentectomy. Ann Thorac Surg 2014;97:1694–700. [6] Asamura H, Hishida T, Suzuki K, Koike T, Nakamura K, Kusumoto M et al. Radiographically determined noninvasive adenocarcinoma of the lung: survival outcomes of Japan Clinical Oncology Group 0201. J Thorac Cardiovasc Surg 2013;146:24–30. [7] Nakamura K, Saji H, Nakajima R, Okada M, Asamura H, Shibata T et al. A phase III randomized trial of lobectomy versus limited resection for smallsized peripheral non-small cell lung cancer ( JCOG0802/WJOG4607L). Jpn J Clin Oncol 2010;40:271–4. [8] Okada M, Koike T, Higashiyama M, Yamato Y, Kodama K, Tsubota N. Radical sublobar resection for small-sized non-small cell lung cancer: a multicenter study. J Thorac Cardiovasc Surg 2006;132:769–75. [9] Schuchert MJ, Pettiford BL, Keeley S, D’Amato TA, Kilic A, Close J et al. Anatomic segmentectomy in the treatment of stage I non-small cell lung cancer. Ann Thorac Surg 2007;84:926–33. [10] Tsutani Y, Miyata Y, Nakayama H, Okumura S, Adachi S, Yoshimura M et al. Oncologic outcomes of segmentectomy compared with lobectomy for clinical stage IA lung adenocarcinoma: propensity score-matched analysis in a multicenter study. J Thorac Cardiovasc Surg 2013;146:358–64. [11] Okada M, Mimura T, Ikegaki J, Katoh H, Itoh H, Tsubota N. A novel videoassisted anatomic segmentectomy technique: selective segmental inflation via bronchofiberoptic jet followed by cautery cutting. J Thorac Cardiovasc Surg 2007;133:753–8.
doi:10.1093/mmcts/mmu025 published online 12 December 2014.
MMCTS
CARDIO-THORACIC SURGERY
Total thoracoscopic posterior basal segmentectomy for primary lung cancer Wataru Nishio*, Kenta Tane, Kazuya Uchino and Masahiro Yoshimura Department of Chest Surgery, Hyogo Cancer Center, Akashi, Japan *Corresponding author. Department of Chest Surgery, Hyogo Cancer Center, 13-70 Kitaoji-cho, Akashi, Japan. Tel: +81-78-9291151; fax: +81-78-9292380; e-mail: [email protected] (W. Nishio). Received 12 August 2014; revised 9 October 2014; accepted 12 November 2014
Summary This report introduces a hilar side approach for posterior basal segmentectomies by the process of specific vision thoracoscopic surgery, which has been used extensively for peripheral small lung cancer by the author. Although it requires a deeper understanding of hilar anatomy and fine control, it is safer and less invasive to the thoracic wall and results in less postoperative pain than the thoracotomy counterpart and as a hilar side approach allows for less deformation. The necessary order of processes involves specific vision, inflation– deflation and blunt dissection from the hilum. Keywords: Thoracoscopy • Segmentectomy • Lung cancer
INTRODUCTION Although it has restricted accessibility and operability relative to thoracotomies, total thoracoscopic surgery (TS) is a reasonable approach for limited lung resection due to being less invasive to the thoracic wall and resulting in relatively less postoperative pain. Furthermore, TS is a common procedure for lobectomies [1]. As operative skills and devices improve, TS is increasingly being used for segmentectomies [2, 3]. The author has performed multiple segmentectomies for lung cancer using mini-thoracotomies, but now exclusively uses TS [4]. In the case of primary lung cancer, there are metastases along the lymphatic system [5]. Consequently, anatomical segmentectomy is preferential by generally first identifying all segmental veins in the hilum, severing the pulmonary artery(ies), veins and the bronchus, and then excising the lung parenchyma from the hilum to the periphery along the intersegmental veins. This does not apply to posterior basal segmentectomies (S10 segmentectomies) as the basal segmental veins do not diverge widely or consistently, and it is difficult to identify them at the hilum. Furthermore, it is difficult to secure B10 and A10 without first separating the lung parenchyma as their diverging points are situated deeply. For these reasons, S10 segmentectomies tend to be avoided even with thoracotomies, let alone with TS. This report introduces a relatively simpler hilar side approach for S10 segmentectomies by the process of a specific perspective TS.
identified with relatively high confidence. The most apparent indication to perform a segmentectomy is if the lung cancer is radiologically non-invasive (consolidation to a tumour ratio of 0.5 or less in clinical T1a-b) and if wedge resection cannot ensure the resectional margin due to the depth of the cancer, and for radiologically invasive cancer (consolidation to a tumour ratio of greater than 0.5 in clinical T1a) segmentectomies are performed when the case is assigned to the segmentectomy group of the JCOG 0802 trial [6, 7]. The trial, however, is not appropriate for respiratory comorbid patients suffering from chronic obstructive pulmonary disease, for patients who have received a lung resection or for patients who have multiple ground glass opacities. In these cases, segmentectomy is advocated.
Preparation The distribution of the bronchi and pulmonary vessels is identified with a three-dimensional CT reconstruction. The basal bronchus generally diverges into B8 and B9 + 10. Notice must be taken of the sub-superior segmental branch (B*), or B10a, as it may need to be severed prior to securing B10 (Fig. 1). If the tumour is situated near the segmental border and it is expected to not be properly identified thoracoscopically, then CT-guided needle marking is preferred preoperatively.
Strategy of four-port VATS SURGICAL TECHNIQUE Patient selection Thin-slice CT results are the primary criteria in determining the procedure to be used as the malignancy of a tumour can be
The author performs every lobectomy and segmentectomy procedure with four ports to ensure control comparable with open thoracic surgery (see Fig. 2 for port location). All ports are wrapped with Lap Protector (Hakko Co. Ltd, Nagano, Japan) silicone sleeves both to protect from contamination and to facilitate changing devices.
© The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
W. Nishio et al. / Multimedia Manual of Cardio-Thoracic Surgery
A rigid 30° diagonal vision thoracoscope is used and inserted through the most appropriate caudal port to allow the visual axis to align with the major fissure. The two devices used by the operator are inserted independently from the two ports and they sandwich the thoracoscope (coaxial approach and triangle formation). An assistant provides the operative field and adds counter-traction by crossing the two devices from the fourth port (Fig. 3). Commonly used instruments are shown in Fig. 4. In segmentectomies, when dissecting along the intersegmental plane from the
2
hilum, many small veins that flow into intersegmental veins should be severed. Ultrasonic shears (Harmonic Ace, Ethicon, NJ, USA) are preferred as they can simultaneously seal and sever small vessels, reducing operation time.
Separating B6 and the basal bronchus The first port is routinely made on the anterior mid-axillar line in the seventh intercostal space for lower lobe lobectomies and segmentectomies. After confirming the status of the thoracic cavity by thoracoscope, interlobar manipulation is then performed. Unless there is incomplete lobulation, the basal segmental artery on the interlobar plane is secured and retracted. Behind the artery, the bifurcation of B6 as well as the basal bronchus is exposed.
Isolating S10 from S6 After turning the lower lobe anteriorly, the mediastinal pleura is incised. A distal dissection is made along V6b and V6c. The lateral wall of the basal bronchus and artery are identified and repositioned downwards from the lung parenchyma, allowing access to the interlobar plane. Dissecting forceps are inserted posteriorly towards the bifurcation of B6 and the basal bronchus on the interlobar plane. A silicone drain is passed along this route as a directional guide. S10 is isolated from S6 by mechanical stapling (Video 1). Tunnelling under the parenchyma reduces risk to the pulmonary arteries by distancing them. Repositioning the parenchyma allows the surgical margin with relative ease. If the cancer in S10 were near the S6 border, the dissection line would be into S6. However, if the cancer were in S10 along the S9 border, the dissection would be set between S6 and S9 and the operative method would have been converted to an S9 + S10 bisegmentectomy (Fig. 5).
Inflation–deflation Figure 1: B9 and B10 diverge in the centre of the lower lobe. B* or B10a diverges to the rear acting as a barrier.
B* (or B10a) is severed at this time. B10 is secured and the anaesthesiologist advances the bronchoscope through B10 to perform
Figure 2: All ports are covered with silicone sleeves. In upper or middle lobectomies or segmentectomies, all ports are shifted up one intercostal space.
3
W. Nishio et al. / Multimedia Manual of Cardio-Thoracic Surgery
Figure 3: In our four-port strategy for posterior basal segmentectomy, the operator stands on the back side, as opposed to the standard ventral side, because most hilar manipulations are more easily performed from the back.
Figure 4: Preference card: 1. Rigid 30° diagonal view scope; 2. Cotton ball (Thoraco Cotton, Kenzmedico Co. Ltd, Saitama, Japan); 3. Grasping forceps for TS, fine DeBakey; 4. Dissecting forceps for TS, fine Maryland; 5. Suction, pencil-shaped; 6. Waldfuss tear drop forceps; 7. Surgical stapler (Endo GIA 45 mm Purple and Black Reload, Covidien, MA, USA). When the assistant provides the operative field, it is preferred to use cotton balls as it is non-invasive to the lung parenchyma and adding countertraction by crossing two cotton balls expedites pleural dissection.
jet ventilation on S10. B10 and A10 are severed. V10 is severed as it runs inside S10. Retracting the distal B10 stump allows for clear identification of V6, V8 and V9 (Video 2).
Video 1: S10 is isolated from S6 by tunnelling under the intersegmental plane, and identifying the basal segmental arteries, veins and bronchus. A thoracoscopic magnified and upward view is used. The inflation–deflation method is not required.
bronchioles are found, they should be sutured. In most cases, the amount of air leakage is low (Video 4). A fibrin sealant is applied to the raw surfaces of the remaining lung to prevent air leakage after electrocautery.
RESULTS
Completing the resection S10 is bluntly isolated from S9 along V9a and V9b from the hilum using the demarcation line as a reference. While performing these procedures in the hilum, the demarcation line will have emerged clearly on the lung’s surface. Electrocautery is used to dissect along the demarcation line until mechanical stapling becomes viable, avoiding postoperative fistula of the bronchioles (Video 3).
Wrapping up The subcarinal lymph nodes are dissected similarly to a lower lobectomy. The air-leak test is performed and if fistulae of the
Four cases of total thoracoscopic segmentectomies were performed as detailed above from February 2013 to May 2014 on two right S10, one left S10 and one left S9 + S10 segments. All cases had not had pathological diagnoses preoperatively, but had been highly suspected of having lung cancer with radiological findings by thin-slice CT. No blood transfusions were required. One patient suffered from atrial fibrillation postoperatively, and medication was sufficient to recover sinus rhythm. All patients were diagnosed with primary lung cancer (adenocarcinoma) postoperatively. No hilar lymph node involvement was observed. Two tumours were pathologically graded as T1aN0 and the other two as T2aN0 due
4
W. Nishio et al. / Multimedia Manual of Cardio-Thoracic Surgery
Figure 5: B9 + 10 and A9 + 10 are clearly visible after severing along V6b and V6c. Video 3: Resection of S10 from S9 in three steps.
Video 4: Post-resectional view and minimal air leakage. Video 2: Manipulating the hilar structures; inflation–deflation method.
to p2a factor. No tumour recurrence has been noted in follow-ups (Table 1).
DISCUSSION Segmentectomy or lobectomy Segmentectomies for primary lung cancer are often thought of as being more limited and as sacrificing prognosis to preserve pulmonary functions. Some retrospective studies, however, have shown that prognosis with clinical T1a lung cancer is equal to that of standard lobectomies for carefully selected patients [8–10]. As improving diagnostics increase the likelihood of detecting small lung cancer, and redo operations become frequent with increasing life span, so does the requirement and desire for segmentectomies.
Issues with posterior basal segmentectomy In S10 segmentectomies, it is difficult to secure B10 without incising the lung parenchyma and to sever S10 from S9 by only
Table 1: Surgical results Variable Operative time (min) Range Median Bleeding (g) Range Median Chest tube duration (days) Range Median Complication Atrial fibrillation Pathological diagnoses Adenocarcinoma T1aN0 T2aN0
No. of patients (n = 4) 147–269 219 20–160 90 2–4 2 1 2 2
dissecting along the intersegmental veins. This first issue is solved by first dissection of S6 and S10 as mentioned above. The inflation–deflation method is helpful to identify the intersegmental plane between S9 and S10, particularly in peripheral
5
W. Nishio et al. / Multimedia Manual of Cardio-Thoracic Surgery
lesions [11]. This requires an anaesthesiologist, but it is convenient and without complications, that is, cerebral air embolism. The demarcation line emerges clearly between the basal segments as the lower lobe suffers relatively less from emphysema. Mechanical stapling is suitable for severing the segmental bronchus; if it were only severed by ligation, the thread would very likely slip off and the segment would deflate.
Tips for hilar side dissection For operators unfamiliar with segmentectomies, the beginning of hilar side dissection seems to be the most difficult part. Converging segments are narrow near the hilum and demarcation lines do not clearly emerge. This is solved by first retracting the B10 stump and bluntly dissecting to expose the side wall of B9. Once the hilar part of S10 is held up after retracting the B10 stump, the small veins between the intersegmental vein and the resectional segment are exposed. As the small veins are severed from the hilum to the periphery, the parenchyma can gradually be bluntly dissected exposing more small veins along the way, reducing deformation and minimizing sharp dissection from the surface.
Surface dissection Two important technical points should be considered when dissecting from the surface: first, adding significant counter-traction to the resectional plane while excising along the demarcation line by electrocautery on low output. Second, performing the incision at uniform depth along the same path several times to avoid deviating from the correct intersegmental plane, which would cause prolonged postoperative air leakage. Conflict of interest: none declared.
REFERENCES [1] Nicastri DG, Wisnivesky JP, Litle VR, Yun J, Chin C, Dembitzer FR et al. Thoracoscopic lobectomy: report on safety, discharge independence, pain, and chemotherapy tolerance. J Thorac Cardiovasc Surg 2008;135:642–7. [2] Shapiro M, Weiser TS, Wisnivesky JP, Chin C, Arustamyan M, Swanson SJ. Thoracoscopic segmentectomy compares favorably with thoracoscopic lobectomy for patients with small stage I lung cancer. J Thorac Cardiovasc Surg 2009;137:1388–93. [3] Oizumi H, Kanauchi N, Kato H, Endoh M, Suzuki J, Fukaya K et al. Anatomic thoracoscopic pulmonary segmentectomy under 3-dimensional multidetector computed tomography simulation: a report of 52 consecutive cases. J Thorac Cardiovasc Surg 2011;141:678–82. [4] Okada M, Nishio W, Sakamoto T, Uchino K, Yuki T, Nakagawa A et al. Effect of tumor size on prognosis in patients with non-small cell lung cancer: the role of segmentectomy as a type of lesser resection. J Thorac Cardiovasc Surg 2005;129:87–93. [5] Sakairi Y, Yoshino I, Yoshida S, Suzuki H, Tagawa T, Iwata T et al. Pattern of metastasis outside tumor-bearing segments in primary lung cancer: rationale for segmentectomy. Ann Thorac Surg 2014;97:1694–700. [6] Asamura H, Hishida T, Suzuki K, Koike T, Nakamura K, Kusumoto M et al. Radiographically determined noninvasive adenocarcinoma of the lung: survival outcomes of Japan Clinical Oncology Group 0201. J Thorac Cardiovasc Surg 2013;146:24–30. [7] Nakamura K, Saji H, Nakajima R, Okada M, Asamura H, Shibata T et al. A phase III randomized trial of lobectomy versus limited resection for smallsized peripheral non-small cell lung cancer ( JCOG0802/WJOG4607L). Jpn J Clin Oncol 2010;40:271–4. [8] Okada M, Koike T, Higashiyama M, Yamato Y, Kodama K, Tsubota N. Radical sublobar resection for small-sized non-small cell lung cancer: a multicenter study. J Thorac Cardiovasc Surg 2006;132:769–75. [9] Schuchert MJ, Pettiford BL, Keeley S, D’Amato TA, Kilic A, Close J et al. Anatomic segmentectomy in the treatment of stage I non-small cell lung cancer. Ann Thorac Surg 2007;84:926–33. [10] Tsutani Y, Miyata Y, Nakayama H, Okumura S, Adachi S, Yoshimura M et al. Oncologic outcomes of segmentectomy compared with lobectomy for clinical stage IA lung adenocarcinoma: propensity score-matched analysis in a multicenter study. J Thorac Cardiovasc Surg 2013;146:358–64. [11] Okada M, Mimura T, Ikegaki J, Katoh H, Itoh H, Tsubota N. A novel videoassisted anatomic segmentectomy technique: selective segmental inflation via bronchofiberoptic jet followed by cautery cutting. J Thorac Cardiovasc Surg 2007;133:753–8.
