Ann Thorac Surg 1998;65:243
© 1998 The Society of Thoracic Surgeons
Case Reports
Postsegmentectomy Pseudotumor of the Lung
Jerome T. Grismer, MD,
Robert F. Schaefer, MD,
Raymond C. Read, MD
Surgical Service, Little Rock Veterans Affairs Medical Center, and Department of Surgery, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
Accepted for publication August 26, 1997.
Dr Grismer, Surgery Service (112), John L. McClellan Memorial Veterans’ Hospital, 4300 W 7th St, Little Rock, AR 72205.
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Abstract
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After an apicoposterior staple segmental resection for squamous cell carcinoma of the left upper lobe, a "new" mass developed in the remaining upper lobe, 8 months postoperatively. Upon removal, this proved to be an ischemic infarction in the anterior segment. Residual lung rotation may have compounded local lung ischemia secondary to the staple technique of resection. One clue to this pseudotumor development appears to be prolonged postoperative "haziness" on chest roentgenograms.
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Introduction
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A pseudotumor of the lung is a benign fibrous lesion that grossly or radiologically resembles a neoplasm. Pulmonary thromboembolism with subsequent infarction is the most common cause [1][2][3]. Definitive diagnosis is difficult without surgical excision. We report an unusual cause of pseudotumor that appeared adjacent to a previous segmentectomy for bronchogenic carcinoma (Fig 1A). This patient, 8 months postoperatively, presented with a mass in the anterior segment of the left upper lobe. Because the computed tomographic scan demonstrated spiculation, a diagnosis of local recurrence was made (Fig 1B). Reoperation revealed pseudotumor.
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Composite of computed tomographic scans depicting the left lung field. (A) Original lung cancer in the apicoposterior segment, left upper lobe (8/25/94). (B) Eight months postoperatively, new lesion in anterior segment, left upper lobe (4/18/95).
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A 59-year-old man, despite a laryngectomy on July 20, 1994, for squamous cell carcinoma, continued a lifelong cigarette habit through his tracheostomy. A chest radiograph on August 25, 1994, confirmed a left upper lobe lesion, which had been noted before laryngectomy (Fig 2: 1).
Sputum cytologic examination continued to show malignant cells. He had an uneventful left apicoposterior segmentectomy on August 31, 1994. Postoperative pathologic staging was peripheral squamous cell carcinoma (T1 N0 M0). There was a question as to whether this was primary bronchogenic carcinoma or metastatic from his laryngeal carcinoma.
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Composite of posteroanterior chest radiographs depicting the left lung field. (1) The appearance of the original neoplasm (8/19/94). (2) Postoperative appearance at 9 days. (3) Eight months postoperative presentation 4/18/95.
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We were consulted 8 months postoperatively. Retrospective examination of the one available postthoracotomy chest roentgenogram revealed a haziness in the left upper lobe at 9 days, which had been attributed to resolving pleural change (Fig 2: 2). At the time we saw him (April 26, 1995), the chest radiogram showed a "new" left upper lobe lesion inferior to the staples marking the site of resection (Fig 2: 3), better demonstrated by computed tomographic scan (see Fig 1B). The radiologic interpretation was "recurrent" cancer. Bronchoscopy revealed a well-healed segmental stump of the left upper lobe. Sputum cytology was normal. The patient had exploratory thoracotomy on May 19, 1995, and resection of the remaining upper division of the left upper lobe (anterior segment) with its contained mass. The specimen displayed a 3 x 3-cm tumor having, on microscopic examination, a dense matrix of scar but no neoplasia in either the lung or hilar lymph nodes. The diagnosis was pseudotumor composed of a circumscribed area of necrosis and infarction.
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Comment
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Conservative resection for cancer of the lung by segmentectomy, using the modern stapling variation, does not clearly define the venous drainage in the intersegmental plane. The surgeon secures the major arterial and venous structures as well as the bronchus at the segmental origin, then finger-dissects along the cut distal bronchus through to the pleural surface. The surgeon adjusts the stapler position to gain adequate margins around the tumor.
In this case we postulate that the original tumor was not located centrally in the apicoposterior segment and the line of resection was designed to remove the tumor rather than perform a classic segmentectomy. Presumably, the vascular supply to a portion of the remaining anterior segment was compromised and this area subsequently progressed to ischemic infarction and fibrosis. Another possibility is that, during division of the blood supply to these segments, part of the arterial supply or venous drainage of the remaining anterior segment was taken. Regardless, ischemia developed analogous to that after thromboembolism. This possibility exists especially in segments with as much variability in their blood supply as is known to exist in the left upper lobe [4]. We further postulate, based upon the sequential chest radiographs, computed tomographic scans, and our operative findings, that the remaining upper lobe, ie, lingula and anterior segment, reoriented cephalad, moving into the apex of the thorax. This rotation, moving the remaining upper lobe posteriorly and inferiorly along the oblique fissure, may have further compromised the marginal blood supply to the anterior segment. In addition, it moved the remaining anterior segment away from the surgical clips, inducing the radiologist to diagnose recurrent cancer. Torsion and venous infarction is a known complication that can occur when the segments of the middle lobe remain after pulmonary resection [5].
In retrospect, one clue may have been the lung "haziness" about the metallic clips at the resection site on radiographs, demonstrated 9 days postoperatively (see Fig 2: 2). This is too extensive to ascribe to postoperative pleural change alone. It was replaced 8 months postoperatively by a lung mass dissociating itself from the metal clips, a sign that radiologists associate with recurrence (see Fig 2: 3). Most surgeons are loath to wait and see if such a lesion grows. In retrospect, could reoperation have been avoided by preoperative needle biopsy? Our suspicion would not have been allayed by a negative percutaneous transthoracic biopsy. Unfortunately, pulmonary cancers and pseudotumors share radiologic similarities, which at times require operative intervention for resolution [4].
This case emphasizes that staple segmentectomy may produce a pseudotumor indistinguishable from recurrent cancer. Reoperation has usually been the best option in the high-risk veteran population with chronic lung disease and heavy tobacco use because conservative resection has been associated with a higher recurrence rate than lobectomy [6].
In conclusion, experience with this patient suggests that if the postoperative haziness of the immediate resection site is more extensive than usual, any subsequent mass that appears, even if its position in relation to surgical clips has shifted, should be considered a pseudotumor and reoperation deferred. The development of such a lesion is more likely when the primary lung tumor lies eccentrically in a segment and the intersegmental plane is not dissected completely. Care should be taken during segmentectomy that the blood supply to and drainage from adjacent segments are not compromised.
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Acknowledgments
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We are indebted to C. Barry Buckner, MD, Associate Professor of Radiology, for his review of the radiographs and his helpful comments in the development of this article.
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References
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- Starzel TE, Brittain RS, Hermann G, Marchioro TL, Waddell WR Pseudotumors due to pulmonary infarction. Am J Surg 1963;106:619-627.[Medline]
- Rabin CB, Murray GB Golden’s diagnostic radiology—radiology of the chest. Baltimore: Williams & Wilkins, 1980:383-387.
- Louie S, Corbett MG, Lillington GA Pseudo-pseudo-pseudotumor of the lung. Chest 1985;88:470-471.[Abstract/Free Full Text]
- In: Shields TW, ed. General thoracic surgery, 4th ed. Philadelphia: Williams & Wilkins, 1994:80-90.
- Wong PS, Goldstraw P Pulmonary torsion: a questionnaire survey and a survey of the literature. Ann Thorac Surg 1992;54:286-288.[Abstract]
- Stair JM, Womble J, Schaefer RF, Read RC Segmental pulmonary resection for cancer. Am J Surg 1985;150:659-664.[Medline]
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Abstract
Introduction
