|
|
||||||||
Guest Access | Sign In via User Name/Password |
|||||||||

*
From the Departments of Thoracic Oncology (Drs. Schouwink, Van Zandwijk, and Baas), Surgical Oncology (Drs. Rutgers and Zoetmulder), and Experimental Therapy (Dr. Stewart and Mr. Oppelaar), The Netherlands Cancer Institute, Amsterdam, the Netherlands; and the Departments of Thoracic Oncology (Dr. Burgers), Surgical Oncology (Dr. van der Sijp), and Clinical Physics (Mr. van Veen), University Hospital Rotterdam/Daniel, Rotterdam, the Netherlands.
Currently at the Department of Pulmonary Diseases, Medisch Spectrum Twente, Enschede, The Netherlands.
Correspondence to: Paul Baas, MD, PhD, FCCP, Department of Thoracic Oncology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands; e-mail: p.baas{at}nki.nl
| Abstract |
|---|
|
|
|---|
Design: Phase I/II dose escalation study.
Setting: Two Dutch cancer centers.
Patients: The study included 28 patients (2 women, 26 men), with pathologically confirmed MPM. The mean age was 57 years (age range, 37 to 68 years), and the World Health Organization performance score was 0 to 1. Epithelial mesotheliomas were found in 17 patients, a sarcomatous mesothelioma was found in 1 patient, and mixed epithelial sarcomatous mesotheliomas were found in 10 patients.
Methods: Patients were injected with 0.075 mg/kg (4 patients), 0.10 mg/kg (19 patients), or 0.15 mg/kg (5 patients) mTHPC 4 or 6 days before undergoing surgery and IPDT. Complete surgical resection (ie, pleuropneumonectomy) was followed by integral illumination with monochromatic light of 652 nm (10 J/cm2). The real-time fluence rate measurements were performed using four isotropic detectors in the chest cavity to calculate the total light dose.
Results: Dose-limiting toxicity was reached at the level of 0.15 mg/kg mTHPC. Three patients died in the perioperative period, and one death was directly related to photodynamic therapy. Real-time dosimetry identified 12 patients in whom additional illumination had to be given to the diaphragmatic sinuses, which were unavoidably shielded during integral illumination. In two patients, illumination was cancelled due to the insufficient resectability of the tumor. The median survival time for all 28 patients was 10 months. Local tumor control, 9 months after treatment, was achieved in 13 of the 26 patients treated with IPDT.
Conclusion: IPDT using mTHPC, combined with a pleuropneumonectomy, resulted in local control of disease in 50% of the treated cases. The considerable toxicity associated with the procedure, however, precludes its recommendation for widespread use. Stricter patient selection and improvements of the IPDT technique may reduce the toxicity.
Key Words: extrapleural pneumonectomy light dosimetry malignant pleural mesothelioma meta-tetrahydroxyphenylchlorin photodynamic therapy
| Introduction |
|---|
|
|
|---|
| Materials and Methods |
|---|
|
|
|---|
Study Design
the dose levels of mTHPC used were 0.075, 0.1, and 0.15 mg/kg.
In phase I of the study, four patients were treated on each dose level,
with surgical resection and illumination at 4 days after IV injection
of mTHPC. Significant perioperative morbidity and/or mortality was
considered to be the dose-limiting toxicity level, and a dose level
below that was considered to be the maximum tolerable dose. An
additional group was created who received a dosage level at
dose-limiting toxicity (ie, 0.15 mg/kg) with a longer
interval between drug administration and illumination of 6 days,
assuming that this would be less toxic than the same drug dose with
illumination after 4 days. Once the maximum tolerable dose had
been defined (ie, 0.1 mg/kg mTHPC with illumination at 4
days), this group was expanded to include 15 more patients as a phase
II study.
Surgical Procedure
The surgical and IPDT procedure used has been described
previously.9
In short, patients were intubated selectively
by a double-lumen endotracheal tube and were placed in a lateral
decubitus position. A posterolateral thoracotomy was performed, and
previous entrance ports were excised. In selected cases, a Cavitron
ultrasound surgical aspirator (ValleyLab; Boulder, CO) was used to
limit blood loss and to facilitate the resection of the tumor. The aim
was to remove all macroscopic sections of the tumor. Small residues of
< 5 mm of the tumor were accepted, if they could not be removed
without disrupting normal anatomic boundaries like the diaphragm and
the pericardium, in order to avoid local tumor spread. Staples were
used to close the bronchial stump, and an ipsilateral
mediastinal lymph node dissection was performed. After this procedure,
the IPDT was performed (see below), followed by closure of the
thoracotomy and immediate extraction of the breathing tube. The
patients were monitored in the ICUs. Oxygen saturation was measured for
only a few minutes every hour during the patients stay in the ICU, to
avoid skin burn lesions induced by the light of the oximeter. Digoxin
was started the day before the operation, and oral anticoagulants were
given postoperatively for a period of 3 months. After discharge from
the ICU, patients stayed in the hospital until they had recovered
sufficiently. Patients were monitored six times during the first year
and three times per year thereafter with physical examinations,
standard laboratory tests, chest radiographs, and CT scans of the
thorax and upper abdomen.
IPDT Procedure
According to the protocol, doses of 0.075, 0.1, or 0.15 mg/kg of
mTHPC (Foscan; Scotia Pharmaceuticals Limited; Surrey, UK) were
administered to the patient 4 or 6 days before illumination. Twenty
milligrams of the drug was dissolved in 5 mL of a solvent containing
ethanol, polyethylene glycol, and water. The solution was shaken
vigorously for 5 min, and this procedure was repeated once more after
1 h, before slow-push IV administration of mTHPC (4 mg/mL).
Patients were nursed in subdued light for 2 weeks. After the
extrapleural pneumonectomy, the chest cavity was extensively inspected
and bleeding lesions were coagulated. Isotropic light probes
(Cardiofocus; West Yarmouth, MA) that were inserted into sterile
transparent tubes 1 to 2 mm in size (Vygon; Ecouen, France) were
sutured onto strategic sites in the cavity (ie, apex,
posterior diaphragmatic sinus, pericardium or anterior chest wall, and
near the esophagus). These isotropic probes measure the fluence rate
delivered to the tissue, including both direct incident and scattered
light from the tissue (Fig 1 ). The isotropic probes were connected to photodiodes (Photop UDT-455;
Graseby Electronics; Orlando FL). These signals were transmitted to a
personal computer for data recording and real-time display. A
transparent sterile plastic bag (Steri-Drape; 3M Corp; St. Paul, MN)
was placed in the cavity and filled with sterile saline solution (2.5
to 4 L) at body temperature for better expansion of the diaphragm and
mediastinal folds. The surgical wound was approximated, and a spherical
bulb fiber 3 mm in diameter (Cardiofocus) was inserted into the center
of the bag. Laser light of 652 nm was obtained from a 6-W diode laser
(Applied Optronics; South Plainfield, NJ). Integral illumination of the
chest cavity was achieved by positioning the bulb fiber so that the
isotropic detectors indicated comparable fluence rates. After integral
illumination, the plastic bag filled with saline solution was removed
from the chest cavity. If one of the measured locations was
insufficiently illuminated, one or two of the isotropic detectors were
moved to the vicinity of this location and additional illumination was
subsequently given by a handheld microlens or spherical diffuser. The
total fluence delivered to the tissues was approximately 10
J/cm2. Before and after the procedure, all
isotropic detectors were checked for their performance and were
calibrated for measurements in saline solution (ie,
correction of the refractory index induced by the saline solution).
Further details on the calibration have been reported by Marijnissen
and Star.11
|
| Results |
|---|
|
|
|---|
|
|
|
|
Postoperative Treatment Mortality
The first serious adverse event resulting in death occurred in a
69-year-old man injected with 0.15 mg/kg mTHPC 4 days before his
operation. A large fibrotic tumor mass hampered complete tumor
resection. Hypotension developed due to blood loss, and the patient was
transfused with 15 U packed RBCs. The light delivery was uneventful. On
the first day after surgery, a myocardial infarction was diagnosed. The
patient died on day 6 postoperatively, despite extensive supportive
measures. At the postmortem examination, severe generalized vascular
atherosclerosis was observed as well as a large anterior myocardial
infarction. Necrotic tumor nests were found in the dorsal sinuses
without viable tumor cells, indicating that PDT had been effective.
The second patient who died was a 56-year-old man with a right-sided pleural mesothelioma, who died 13 days after treatment with 0.15 mg/kg mTHPC and a 6-day interval before IPDT. Surgery and IPDT passed without obvious problems. Left-sided pleural fluid (an exudate) was drained 7 days after treatment. Eleven days after the operation, a sudden deterioration of his clinical condition occurred. Bronchoscopy revealed a right bronchopleural fistula. A rethoracotomy was proposed but was refused by the patient. He died on day 12 after treatment. At autopsy, the bronchopleural fistula was confirmed with diffuse inflammation and extensive formation of debris in the right chest cavity. A culture of tissue from the cavity showed Klebsiella pneumonia and several Streptococcus species.
The third death was in a patient treated with 0.1 mg/kg mTHPC with a 4-day interval before illumination. In this case, the illumination was not performed strictly according to the protocol. This was due to an abnormal geometry of the left chest cavity. One isotropic detector was placed in the apex of the cavity, and three probes were placed on and around the diaphragm. This resulted in an overdose in the region of the esophagus and the heart. The patient developed an esophageal fistula after 7 days, which was corrected with placement of an omentum flap and the construction of a Clagett thoracotomy. On day 12, bleeding occurred in the chest cavity. In this patient, no anticoagulant therapy was administered. Despite intensive supportive treatment, the patient died. A postmortem examination revealed diffuse bleeding from multiple sites and necrosis in the margins of the esophageal fistula. Typical PDT-induced necrosis was observed in the epicardia reaching into the myocardium without coronary artery occlusion.
Postoperative Morbidity
The mean hospital stay was 28 days, ranging from 18 to 61 days
(Table 2) . The majority of patients (23 patients; 82%) had one or more
postoperative complications, varying from pain in the surgical scar to
diaphragmatic rupture or myocardial infarction. Congestive heart
failure and atrial fibrillation were the most frequent side effects.
Empyema occurred in four patients 3 to 6 months after the procedure.
One of these patients had only been resected and not treated with IPDT.
In some cases, complications such as excessive intrathoracic fluid
accumulation could be attributed to the IPDT. In others, complications
such as atrial fibrillation might have been elicited by the
pleuropneumonectomy. In the majority of cases, it was difficult to
attribute complications specifically to either modality. However, no
further patients were enrolled in the 0.15 mg/kg dose group after the
second fatality. The 0.1 mg/kg group was subsequently expanded.
One of the two female patients (0.1 mg/kg dose group) had two major complications. She suffered from a diaphragmatic rupture with displacement of the stomach into the chest cavity on day 14 after treatment, which required surgical intervention. Tissue samples taken during the rethoracotomy showed a very thin muscle layer without evidence of PDT-induced necrosis. This patient subsequently developed a cardiac tamponade on day 14 during anticoagulant therapy. A pericardial drain was inserted. The hemorrhagic effusion revealed no malignant cells. This patient recovered successfully.
Another patient (0.15 mg/kg mTHPC with 4-day interval before IPDT) experienced a perioperative myocardial infarction and, subsequently, a spinal cord infarction due to hypotension caused by severe blood loss. The tumor had grown into the subclavian artery wall and into the myocardium. A vascular prosthesis had to be inserted in the resected subclavian artery. This patient was discharged on day 60 to a rehabilitation center.
Skin phototoxicity was not a significant clinical problem in our study, and no sunlight-induced skin toxicity was observed. Skin burn effects were seen most frequently in the 0.15 mg/kg dose group (2 of 5 patients). This was induced by the surgical theater lights despite the covering of the wound edges with green surgical drapes.
Site of Recurrence
During follow-up, the following three types of recurrences could
be identified: local; in the surgical scar; and distant. Recurrence was
established in 20 patients. There were eight patients with local
recurrences, four patients with recurrences in the surgical scar, and
eight patients with distant recurrences (Table 4
). Local disease control at 9 months was achieved in 13 of the 26
patients treated with surgery and IPDT.
|
|
| Discussion |
|---|
|
|
|---|
In our study, we have tried to optimize one of the treatment parameters, drug dose, using a new delivery procedure for IPDT in patients with MPM. It is nearly impossible to analyze all PDT factors (ie, drug dose, light dose, and drug/light interval) adequately in one study. We focused on varying the drug dose, while maintaining both the light dose and the drug/light interval. The differences in the extent of the surgical procedure also significantly influenced the final result and toxicity. Despite careful preoperative screening, some patients were found to have an nonresectable tumor during the surgical procedure. In three patients with extensive resections of tumor invading vasculature or the chest wall, IPDT was given according to the protocol. These patients had significant perioperative and postoperative complications, as mentioned above. Such patients should, therefore, probably be excluded from IPDT, and more stringent attempts should be made to identify patients with nonresectable tumors preoperatively. MRI,17 18 19 three-dimensional tumor volume estimation,20 and standardized uptake values of fluorodeoxyglucose positron emission tomography scanning21 22 may improve the selection of patients for surgically based therapy.
Until recently, MPM was thought to be primarily a local disease.23 If this is true, successful local control should significantly improve survival times. However, autopsy reviews have indicated that > 50% of patients with MPM develop distant metastases,24 25 and Sugarbaker et al26 also have demonstrated the prognostic importance of local (mediastinal) lymph node involvement. We have routinely incorporated a mediastinoscopy into the preoperative assessment of our patients in order to exclude those patients with mediastinal lymph node metastases. Rusch and Venkatraman27 showed that one quarter of mediastinal lymph nodes in patients with MPM were not accessible to cervical mediastinoscopy. In comparison with patients with non-small cell lung cancer, a relatively large number of MPM patients have nodal disease confined to areas such as the peridiaphragmatic area or internal mammary chains. Improvements in local control of disease therefore should be integrated with effective systemic therapy to obtain a better prognosis for this disease in general.
Phase I of our study demonstrated that a dose of 0.1 mg/kg mTHPC given 4 days before IPDT is the maximum tolerable dose. The IPDT could be given in a short period of time, which is one of the advantages of a potent photosensitizer such as mTHPC. The treatment, however, did still lead to considerable morbidity. An analysis of the toxicities in this study is complicated by the multimodality approach. Pleuropneumonectomy alone leads to significant toxicity, with a mortality rate of about 10 to 15%,28 which is comparable to that seen in the present combined-modality study. Right-sided resections carry the greatest surgical risk, and the majority of our patients (19 of 28) had right-sided disease. This might have influenced the results in a negative way. Large-surface PDT alone also would be expected to be associated with significant toxicity. In our study, the perforation of the esophagus clearly was related to the IPDT procedure. This fatal complication illustrates the importance of light dosimetry on more than one location. Temeck and Pass29 have reported this complication as a dose-limiting factor in Photofrin-mediated IPDT in two MM patients. With respect to the IPDT-induced cardiac damage, a side study was initiated measuring T-troponin levels and performing cardiac examinations during surgery and after. No significant myocardial damage was observed in five patients treated with 0.1 mg/kg mTHPC 4 days before IPDT,30 when the illumination procedure was performed in a standard way.
Our study addressed the influence of the sensitizer dose on IPDT-related toxicity. With the exception of two patients treated 6 days after injection of mTHPC, the drug/light interval was kept constant at 4 days and only limited variations in total fluence were allowed. These choices were based on reports in the literature and our own experience.31 32 The light delivery system used in this study is now thoroughly tested and is, in our opinion, an important improvement for the application of PDT in general. Other investigators13 have used photodiode light detectors, which measure only incident light fluence, and not scattered and reflected light. Such detectors clearly give an underestimation of the total fluence delivered to the tissue surface.33 The use of only four detectors placed on strategic sites in the chest cavity and a single spherical bulb fiber placed in the center of a fluid-filled transparent bag in the chest cavity allowed adequate integral illumination of the entire cavity in most cases. In view of the patient who was overdosed with light, we stress that it remains critical that detectors are placed with care and kept in their positions during the full procedure.
Some sites, like the diaphragm, can be shielded from the light, but they are easily detected by this system using real-time dosimetry. Additional illumination can be administered with the isotropic bulb or lens fiber after completing the integral treatment. A possible disadvantage of our system is the pressure on surrounding tissue induced by the fluid-filled bag. Pressure against malignant and healthy tissue could perhaps reduce PDT efficacy due to decreased tissue perfusion accompanied by decreased oxygenation.34 35
In conclusion, the combination of extensive surgical resection and IPDT was too toxic to be advocated as a widespread treatment option for patients with MPM. The use of intraoperative dosimetry devices is considered to be a prerequisite. Further studies should be performed with more limited surgical resections. Light doses of 10 J/cm2 at 4 days after the administration of 0.1 mg/kg mTHPC resulted in significant toxicity in this patient group. Local control of disease, however, could be achieved in half of the treated patients. Improvements in terms of clinical usefulness can be expected from stricter patient selection and PDT-related technical improvements (eg, specific illumination devices for treatment of the diaphragmatic gutter).
| Footnotes |
|---|
This study was partly supported by the Dutch Cancer Society (grant No. NKI 97-1446) and by Scotia Pharmaceuticals Ltd, Surrey, England.
Received for publication November 30, 2000. Accepted for publication April 16, 2001.
| References |
|---|
|
|
|---|
This article has been cited by other articles:
![]() |
H. Schouwink and P. Baas Foscan-mediated photodynamic therapy and operation for malignant pleural mesothelioma Ann. Thorac. Surg., July 1, 2004; 78(1): 388 - 388. [Full Text] [PDF] |
||||
![]() |
J. S. Friedberg and S. M. Hahn Foscan-mediated photodynamic therapy and operation for malignant pleural mesothelioma: Reply Ann. Thorac. Surg., July 1, 2004; 78(1): 388 - 389. [Full Text] [PDF] |
||||
![]() |
J. H. Schouwink, L. Schultze Kool, E. J. Rutgers, F. A. N. Zoetmulder, N. van Zandwijk, M. J. v.d. Vijver, and P. Baas The value of chest computer tomography and cervical mediastinoscopy in the preoperative assessment of patients with malignant pleural mesothelioma Ann. Thorac. Surg., June 1, 2003; 75(6): 1715 - 1718. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. van Ruth, P. Baas, and F. A. N. Zoetmulder Surgical Treatment of Malignant Pleural Mesothelioma: A Review Chest, February 1, 2003; 123(2): 551 - 561. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. I. Pass Pleural mesothelioma in 2002: Going somewhere very slowly J. Thorac. Cardiovasc. Surg., December 1, 2002; 124(6): 1074 - 1077. [Full Text] |
||||
![]() |
P. Bonnette, G. B. Heckly, S. Villette, A. Fragola, J. H. Schouwink, and P. Bass Intraoperative Photodynamic Therapy After Pleuropneumonectomy for Malignant Pleural Mesothelioma Chest, November 1, 2002; 122(5): 1866 - 1867. [Full Text] [PDF] |
||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |