Photodiagnosis and Photodynamic Therapy (2006) 3, 3—10
Photodynamic therapy in China: Over 25 years of unique clinical experience Part One—–History and domestic photosensitizers Zheng Huang MD, PhD ∗ Radiation Oncology Department, Colorado University Health Sciences Center, Denver, CO, USA
KEYWORDS Photodynamic therapy; PDT; History; China; Literature survey; Photosensitizer
Summary Photodynamic therapy (PDT) was started in the People’s Republic of China in the early 1980s after domestically produced hematoporphyrin derivative (HpD) became available. Since then, numerous photosensitizers have been synthesized and evaluated. Several promising ones have undergone clinical investigations and a few have entered into formal clinical trials. Various lasers and non-coherent light sources have been developed in China to facilitate domestic photosensitizers and clinical PDT applications. Chinese pioneered PDT protocols for treating nasopharyngeal carcinoma, liver carcinoma, port-wine stains (PWS) and urethral condylomata acuminata. Over the past 25 years Chinese physicians have treated several thousands patients, gained substantial experience in both basic sciences and clinical applications, and generated a great number of clinical reports. PDT related research and clinical activities would most likely continue to grow in China. The Part One of this article provides an overview on China’s PDT history and domestic photosensitizers. Clinical PDT data of nasopharyngeal carcinoma, liver cancer and port-wine stains will be discussed in the Part Two of this article. © 2006 Elsevier B.V. All rights reserved.
Introduction After more than 25 years of clinical practice, photodynamic therapy (PDT) has now become an established modern medical technique in the People’s Republic of China. When China started PDT in the early 1980s, I was a medical student in Suzhou Medical College. At that time, the term of photodynamic therapy, often trans∗
Corresponding author. Tel.: +1 303 239 3567; fax: +1 303 239 3562. E-mail address: zheng [email protected].
lated as photodynamic treatment, could not be found in any medical textbook. PDT procedure was unknown to medical students or clinicians even though the light and dyes have been used as a magic therapeutic power in ancient China. In the 1980s and 1990s, PDT procedures were also often described in Chinese literatures as laser- or photochemotherapy or hematoporphyrin photoradiation therapy or hematoporphyrin (derivative) laser antitumor therapy, mainly due to a high expectation of tumor selectivity of hematoporphyrin derivative (HpD). In the early years, PDT was only available in several elite hospitals in major cities. Now
1572-1000/$ — see front matter © 2006 Elsevier B.V. All rights reserved. doi:10.1016/S1572-1000(06)00009-3
4 it has become much more familiar to Chinese clinicians. Recently, I received two Chinese monographs, an impressive collection of review and clinical articles, used primarily in PDT workshop and training in China [1,2]. I was surprised and even amazed by the profound knowledge and advanced experience accrued in China over the past years. A great number of patients have been treated in China in the past 25 years. Compared to those clinical activities outside China [3], some of Chinese experiences and PDT protocols are certainly reaching advanced levels and could be valuable to the PDT communities outside of China. As a part of the government organized high profile campaign to develop new techniques to fight cancer, Chinese PDT pioneers were able to quickly implement PDT technique equipped with domestic photosensitizers, lasers and experts in the early 1980s [4]. Those early work and progress can be demonstrated in their reports published in mainstream English journals [5—11]. A better understanding of PDT mechanisms has also been demonstrated at the same time [12]. Although some of these early works have been well circulated at medical journals and conferences, some of these publications have been cited by their counterparts outside China. However, most newly developed photosensitizers and clinical work are less well-known outside of China since the number of peer-reviewed publications in English journals is still very limited. On the other hand, a majority of Chinese periodical publications has not yet indexed in major medical databases such as MEDLINE, PubMed or EMBASE. The primary goal of this manuscript is to re-visit some of the early clinical work and meanwhile introduce some of the recent progress on domestic photosensitizers and unique clinical work which might be of interest to PDT communities outside of China. It is still very difficult to search Chinese articles published in the 1980s and early 1990s mainly due to their unavailability in periodical index systems. Data and references presented in this article were obtained through various means. First, a list of Chinese and English articles related to domestic photosensitizers, lasers and clinical applications was created through a number of literature search approaches: 1. Cross-examination of reference lists from journal articles. 2. Chinese Bio-Medical Citation Database (CBMdisc). This searchable database includes the basic citation information such as author(s), title, journal detail and abstract.
Z. Huang 3. Wanfang Data Digital Periodical (Wanfang Data Co., Ltd.). This website provides links to major Chinese biomedical journals. 4. Biomedical databases such as MEDLINE, PubMed and EMBASE. These most frequently used medical literature database can retrieve not only articles published in English biomedical journals but also some Chinese biomedical journals. Then, the full texts of the articles on the list were obtained from: 1. National Journal Full-Text Database (CNKI Digital Library). This Chinese database provides a web-based search tool to retrieve full text from major Chinese medical, biopharmaceutical and healthcare journals from 1994 to 2004. 2. Guangzhou Medical Library and Guangzhou Medical College Library. 3. National Science and Technology Library. 4. Chinese People’s Liberation Army (PLA) General Hospital. 5. Authors and personal collections. Inclusion or omission of these articles will be purely based on the availability. Except for omitting a few single case reports, all clinical reports were reviewed and organized by their clinical specialties in a chronological fashion in the Part Two of the article. Although one of the goals of this review is to include Chinese clinical reports published between 1982 and 2004 and provide, for the first time, a comprehensive list of Chinese PDT literatures, it is inevitable that our literature search could have missed some hard-to-find clinical reports published in local journals.
Revisiting the history The development and application of PDT and PDD (photodynamic diagnosis) in China were started in the early 1980s after the first domestically produced HpD became available between 1980 and 1981. The first PDT case was performed by Dr. Jin Zhou at Beijing Tong-Ren Hospital in July 1981 [13]. The novelty of this modality and its’ great therapeutic potential for the treatment of malignant diseases immediately drew attention and brought excitement in China [4]. The State Science and Technology Commission quickly pointed a multidiscipline task group and initiated a special key research project to develop antitumor photosensitizing drugs, namely hematoporphyrin derivatives
Photodynamic therapy in China Table 1
5
National criterion for the evaluation of short-term therapeutic responses of antitumor PDT (1984) Definitions
Complete remission (CR) Significant remission (SR) Minor remission (MR) No remission (NR)
Visible tumor cleared and no recurrent within a month Reduction in tumor volume is >50% and stable for over a month Reduction in tumor volume is
Photodynamic therapy in China: Over 25 years of unique clinical experience Part One—–History and domestic photosensitizers Zheng Huang MD, PhD ∗ Radiation Oncology Department, Colorado University Health Sciences Center, Denver, CO, USA
KEYWORDS Photodynamic therapy; PDT; History; China; Literature survey; Photosensitizer
Summary Photodynamic therapy (PDT) was started in the People’s Republic of China in the early 1980s after domestically produced hematoporphyrin derivative (HpD) became available. Since then, numerous photosensitizers have been synthesized and evaluated. Several promising ones have undergone clinical investigations and a few have entered into formal clinical trials. Various lasers and non-coherent light sources have been developed in China to facilitate domestic photosensitizers and clinical PDT applications. Chinese pioneered PDT protocols for treating nasopharyngeal carcinoma, liver carcinoma, port-wine stains (PWS) and urethral condylomata acuminata. Over the past 25 years Chinese physicians have treated several thousands patients, gained substantial experience in both basic sciences and clinical applications, and generated a great number of clinical reports. PDT related research and clinical activities would most likely continue to grow in China. The Part One of this article provides an overview on China’s PDT history and domestic photosensitizers. Clinical PDT data of nasopharyngeal carcinoma, liver cancer and port-wine stains will be discussed in the Part Two of this article. © 2006 Elsevier B.V. All rights reserved.
Introduction After more than 25 years of clinical practice, photodynamic therapy (PDT) has now become an established modern medical technique in the People’s Republic of China. When China started PDT in the early 1980s, I was a medical student in Suzhou Medical College. At that time, the term of photodynamic therapy, often trans∗
Corresponding author. Tel.: +1 303 239 3567; fax: +1 303 239 3562. E-mail address: zheng [email protected].
lated as photodynamic treatment, could not be found in any medical textbook. PDT procedure was unknown to medical students or clinicians even though the light and dyes have been used as a magic therapeutic power in ancient China. In the 1980s and 1990s, PDT procedures were also often described in Chinese literatures as laser- or photochemotherapy or hematoporphyrin photoradiation therapy or hematoporphyrin (derivative) laser antitumor therapy, mainly due to a high expectation of tumor selectivity of hematoporphyrin derivative (HpD). In the early years, PDT was only available in several elite hospitals in major cities. Now
1572-1000/$ — see front matter © 2006 Elsevier B.V. All rights reserved. doi:10.1016/S1572-1000(06)00009-3
4 it has become much more familiar to Chinese clinicians. Recently, I received two Chinese monographs, an impressive collection of review and clinical articles, used primarily in PDT workshop and training in China [1,2]. I was surprised and even amazed by the profound knowledge and advanced experience accrued in China over the past years. A great number of patients have been treated in China in the past 25 years. Compared to those clinical activities outside China [3], some of Chinese experiences and PDT protocols are certainly reaching advanced levels and could be valuable to the PDT communities outside of China. As a part of the government organized high profile campaign to develop new techniques to fight cancer, Chinese PDT pioneers were able to quickly implement PDT technique equipped with domestic photosensitizers, lasers and experts in the early 1980s [4]. Those early work and progress can be demonstrated in their reports published in mainstream English journals [5—11]. A better understanding of PDT mechanisms has also been demonstrated at the same time [12]. Although some of these early works have been well circulated at medical journals and conferences, some of these publications have been cited by their counterparts outside China. However, most newly developed photosensitizers and clinical work are less well-known outside of China since the number of peer-reviewed publications in English journals is still very limited. On the other hand, a majority of Chinese periodical publications has not yet indexed in major medical databases such as MEDLINE, PubMed or EMBASE. The primary goal of this manuscript is to re-visit some of the early clinical work and meanwhile introduce some of the recent progress on domestic photosensitizers and unique clinical work which might be of interest to PDT communities outside of China. It is still very difficult to search Chinese articles published in the 1980s and early 1990s mainly due to their unavailability in periodical index systems. Data and references presented in this article were obtained through various means. First, a list of Chinese and English articles related to domestic photosensitizers, lasers and clinical applications was created through a number of literature search approaches: 1. Cross-examination of reference lists from journal articles. 2. Chinese Bio-Medical Citation Database (CBMdisc). This searchable database includes the basic citation information such as author(s), title, journal detail and abstract.
Z. Huang 3. Wanfang Data Digital Periodical (Wanfang Data Co., Ltd.). This website provides links to major Chinese biomedical journals. 4. Biomedical databases such as MEDLINE, PubMed and EMBASE. These most frequently used medical literature database can retrieve not only articles published in English biomedical journals but also some Chinese biomedical journals. Then, the full texts of the articles on the list were obtained from: 1. National Journal Full-Text Database (CNKI Digital Library). This Chinese database provides a web-based search tool to retrieve full text from major Chinese medical, biopharmaceutical and healthcare journals from 1994 to 2004. 2. Guangzhou Medical Library and Guangzhou Medical College Library. 3. National Science and Technology Library. 4. Chinese People’s Liberation Army (PLA) General Hospital. 5. Authors and personal collections. Inclusion or omission of these articles will be purely based on the availability. Except for omitting a few single case reports, all clinical reports were reviewed and organized by their clinical specialties in a chronological fashion in the Part Two of the article. Although one of the goals of this review is to include Chinese clinical reports published between 1982 and 2004 and provide, for the first time, a comprehensive list of Chinese PDT literatures, it is inevitable that our literature search could have missed some hard-to-find clinical reports published in local journals.
Revisiting the history The development and application of PDT and PDD (photodynamic diagnosis) in China were started in the early 1980s after the first domestically produced HpD became available between 1980 and 1981. The first PDT case was performed by Dr. Jin Zhou at Beijing Tong-Ren Hospital in July 1981 [13]. The novelty of this modality and its’ great therapeutic potential for the treatment of malignant diseases immediately drew attention and brought excitement in China [4]. The State Science and Technology Commission quickly pointed a multidiscipline task group and initiated a special key research project to develop antitumor photosensitizing drugs, namely hematoporphyrin derivatives
Photodynamic therapy in China Table 1
5
National criterion for the evaluation of short-term therapeutic responses of antitumor PDT (1984) Definitions
Complete remission (CR) Significant remission (SR) Minor remission (MR) No remission (NR)
Visible tumor cleared and no recurrent within a month Reduction in tumor volume is >50% and stable for over a month Reduction in tumor volume is
