光動力刀診斷及治療From PDT to PDD

謝義山新光吳火獅紀念醫院胸腔外科主治醫師

Content光物理化學 Mini Review光動力刀原理Photophrin 光動力刀治療新光醫院治療經驗Off-Label 光動力刀治療 自體螢光診斷原理新光醫院肺癌篩檢計畫– 自體螢光內視鏡檢查– 低劑量胸部電腦斷層掃描

光物理化學 Mini Review

光子說 粒子、波動雙元性Non-ionizing radiation 帶有能量了粒子　一光子的能量：一量子（ quantum ）或稱光子（ photon ）

E=hν=hc ／ λ h 為 Planck 常數， λ 為波長， c為光速，　 6.02×1023個光子稱為一愛因斯坦。

原子模型量子力學：「能階」， 「軌域」不同的能階對應於不同的電 子能量。不同軌道最多可容納的電子數目 也不同

基態：當原子內所有電子處於可能的最低能階時受激態：當一個或多個電子處於較高的能階時

光電效應

光電效應：吸收及射出特定波長之光

LaserLight Amplication by Stimulated Emission of Radiation

分子的組成

電子軌域 S/P/Q混成軌域

受激分子的能量狀態 量子力學： –分子吸收光子能量後，電子受激在能階上跳動，分子間距改變儲存能量

電子三重態

光對分子之作用 一般電子激動能量乃轉變成振動能量（ Vibrational energy ）（分子中原子的振動），然後再以熱的形式散佈到四周。 螢光及燐光 分子可能受激分解開來，這是所謂的光解作用（ photolysis ）– 臭氧的光解受激分子能進行各種化學轉換（ Chemical

transformation ）– H2 和 Cl2 的連鎖反應– 自由基反應

光照射組織表面反射 Reflection透射 Trasmission散射 Scatter吸收 Absortion

　取決於光的波長，組織的特性及介面

常用醫用雷射效果因素wavelength, intensity, duration of exposure, and tissue-specific response.不同雷射有不同能量

光動力診斷治療光治療 Phototherapy光動力治療 / 光化學治療 Photodynamic therapy / Photochemotherapy自體螢光檢查 Auto-fluorescence Exam

光治療光也有治病的效果1903 年， Niels Ryberg Finsen– 利用光照射治療狼瘡（ Lupus Vulgaris ）而獲得諾貝爾獎新生兒黃膽：照光治療照光刺激表皮脂肪組織合成 Vit D雷射除刺青

光動力刀診斷治療合併藥物 ( 染料 ) 及光線進行診斷治療1900 年，拉伯（ C. Raab ）– 發現經過染料處理過的草履蟲（ paramecia ）在照光後便死亡。如果只給予染料或只照光處理的草履蟲仍然活著。1903 年， von Tappeiner and Jesionek – Topical Eosin and sunlight to treat skin tumor染料＋光 產生破壞細胞組織的化學反應腫瘤細胞特別會吸收這些染料物質

100 年在路上Search for a perfect photosensitizer: – Non-toxic, – Taken up by malignant cell only, – Excited by light of a specific wavelength

Porphyrins and metallo-prophyrins (Figge, 1948)Fluoresceine (Moore 1953)Tetracycline (Rall, 1957) Acridine orange and Ar-laser (Thompson, 1974)

皇天不費苦心人Hematoporphyrin HPD (1975 Dougherty)– Most low toxicity, selectively and

retained in malignant tissue– HPD can be exited by photons in the

presence of oxygen to attain local cytotoxicity

HPD 光動力刀診斷治療1982: Hayata and kato using bronchoscopy system Hematoporphyrin (HPD) or porphyrin derivatives emit real fluorescence when excited by violet lightThe concentration of HPD and porphyrin are higher in malignant tumors than in non-malignant tissueI.v. injection of HPD (3 to 5mg/kg) and 72 hours later optimal differentiation between tumor and normal tissueKrypton-ion laser (406nm, 647nm) for PDDGold vapor Laser (628nm) for PDT

紫質 Porphyrin 的衍生物

光動力刀原理Prophyrin 衍生物在下列的細胞組織內有較佳的吸附能力，也容易積存大量的染料– 惡性腫瘤細胞和腫瘤脈管的細胞層內– 網狀內皮組織（ reticulo- endothelial ）的肝、脾、腎、肺等器官– 動脈硬化血斑（ atherosclertic plaque ）– 發炎或傷口癒合之處等– 表皮

吸附能力不同的假說 (I)癌細胞和其他急劇增長的細胞一樣，在細胞膜生物合成時，需要大量的膽固醇（ cholestrol ），造成對低密度脂蛋白（ low-density lipoprotein ）的需求量增加。而在血液裡的親脂性紫質衍生物（例如血紅素）主要也是藉脂蛋白傳遞至細胞內。因此有可能染料是以同樣的方式進入細 胞內。

吸附能力不同的假說 (II)腫瘤內的 pH值較正常組織低。這造成了紫質衍生物（通常帶有官能基 -COOH ）不易解離，因此大量積存在腫瘤內。 腫瘤通常含有大量的脂質（ lipid ）。尤其是其細胞膜內的脂質含量要比正常細胞高出許多。因此腫瘤細胞要比正常細胞較具厭水性（ hydrophobic ）。這或許就是腫瘤細胞可以積留大量的感光染料（也具厭水性）的原因。

光動力治療法的機制

光動力治療法的機制有氧機制：氧氣Ｏ自由基反應– Type I Mechanism :

• Highly reactive free radicals O. are generated that can damage intracellular membranes and mitochondria

– Type II Mechanism :• Excitation to reactive singlet oxygen .O2 species leads to

oxidation of membranous cell structures無氧機制：無氧雙光子機制 – 通常雙光子光驅動治療是以一道雷射光將染料由基態 S0激發至激發態S1，再經由單重 -三重電子態能量交流至另一個激發態 T1。然後再迅速的以第二道雷射光將染料由 T1激發態激發到更高的激發態 Tn。腫瘤週邊血管栓塞壞死免疫反應 ?

漂白效應 當染料吸收雷射光之後，產生化學反應。其原有的光學性質，無法以同樣的波長產生同樣的效應。因此我們說染料被「漂白」了。 染料的劑量會影響漂白效應的程度。若染料的劑量不能低於某一個限度，否則無法產生足夠的自由基（或單重態氧） ，無法造成 腫瘤組織壞死，儘管雷射光強度再強也。乍看之下好像染料被「漂白」了，不再吸收雷射光。

漂白效應若雷射光的瞬間強度太強，所有處於基態的染料分子均會被激發至激發態。 一般用於光驅動治療的染料的三重態產率相當高（約 0.8左右），又加上其三重激發態的生命期也相當長（約數個微秒），久留在激發態，無法馬上回到基態再吸 收雷射光，造成了瞬間漂白效應（ transient photobleaching）。染料分子被強烈的雷射光激發後也有可能分解，產生非可逆性漂白效應（ irreversible photobleaching）。因此於光驅動治療時，雷射光的強度及照射時間和染料劑量的控制對於治療效果有很大的影響。

遮蔽效應 染料分子的「遮蔽效應」（ selfshielding）這種效應會影響雷射光穿透生物組織的能力（亦即有效治療深度）。一般光驅動治療的雷射光穿透深度在數個釐米左右。若染料對某雷射光波長有強烈的吸收，光強度會因被處於組織表面的染料所吸收而減弱，治療效果無法深 入組織內。抵消遮蔽效應的策略是設法將雷射光波長調離吸收峰之處和降低染料的使用劑量。但如前面所述，染料的使用劑量也不能太低，否則遮蔽效應雖然消失了，漂白效應又會重現。

感光染料的研究與發展

目前發展運用在光驅動治療法的感光染料有三個主要前題： –必須於近紅外線光區域（ 670-750nm）有良好的吸收。因為細胞組織在此區域的光穿透率最高。光驅動治療可更有效的深入體內。 –於腫瘤細胞的吸附能力必須提高。 –在正常組織，尤其是皮膚的聚集能力和積留時間必須減少。

Photofrin®

Porfimer Sodium

Complex chemical entity A mixture of porphyrin oligomers

The Chemistry

Light Absorption Spectra

UV

0.0E+00

1.0E+05

2.0E+05

3.0E+05

4.0E+05

5.0E+05

6.0E+05

300 400 500 600 700

Wavelength (nm)

Rel

ativ

e Ab

sorp

tion

X5

PhotofrinOxyhemoglobin

0.6

0.5

0.4

0.3

0.2

0.1

0.0630

Clearance and Selectivity

Photofrin clears from a variety of tissues in 48 to 72 hours

Photofrin is retained for longer than 48 to 72 hours after administration in:

• tumor tissue and dysplastic cells• Skin and organs of the reticuloendothelial

system (including the liver and the spleen)

Diomed 630 PDT Laser •Portable •Space efficient - 48.5cm [H] x 22cm [W[ x 40.5cm [d] - Weight = 19.5 Kg•No Plumbing required•Standard Electrical Supply•Self-Calibrating •Cost Effective

Step 1: Drug Administration and Selective Accumulation

Photofrin 2 mg/kgslowly administered

(3-5 min)

Step 2: Light Administration= 630 nm, Red Light

48 hours following i.v. adminisatrtion of Photofrin

Step 3: Selective Cell Destruction

Approvals Around the World

United States, Japan and Canada: 1995Europe:17 Countries UK, Ireland, France, Netherland, Finland,

Denmark, Luxembourg, Germany, Iceland, Italy, Norway , Belgium, Poland, Sweden, Austria, & Portugal & Greece

Taiwanis approved at year 2004

FDA & 衛署Approved Indications

Palliation of patients with completely obstructed esophageal cancer, or of patients with partially obstructed esophageal cancer who, in the opinion of their physician, cannot be satisfactorily treated with Nd:YAG laser therapy減低完全阻塞的食道癌患者的症狀﹐或是醫師認為使用 Nd:YAG 雷射療法無法治療之部份阻塞做得好食道癌患者之症狀

FDA & 衛署Approved Indications (con’t)

Reduction of obstruction and palliation of symptoms in patients with completely or partially obstructing endobronchial nonsmall cell lung cancer (NSCLC)減低完全和部份阻塞支氣管非細小細胞肺癌患者的阻塞及症狀緩解

FDA & 衛署Approved Indications (con’t)

Treatment of microinvasive endobronchial NSCLC in patients for whom surgery and radiotherapy are not indicated治療不適合手術及放射治療之患者的微侵犯性非細小細胞肺癌

Other Off-Label Indications

Skin CancerBreast cancerCervical cancerBrain tumors (high grade glioma, single metastasis, skull base tumor, pituitary tumor)Colorectal tumorsGynecologic malignanciesOral cancer

16th World Congress of the International Society for Laser Surgery and medicine

(16th ISLSM) Tadayoshi Kaneko, Takashi Yasuda, Hiroshige Chiba.

Tokyo Medical University, Tokyo, Japan

“.. 13 cases were treated by PDT in about 6 years from June, 1999 to April, 2005. …”

“ 2mg/kg Photofrin 48 hours prior to laser irradiation”“..in the 6-year period, 6 cases showed recurrence,

but the others showed no recurrence or metastasis..”

Contradictions

Photofrin is contradicted in patients with porphyria or in patients with known allergies to porphyrinsPDT is contraindicated in patients with an existing tracheoesophageal or bronchoesophageal fistulaPDT is contraindicated in patients with tumors eroding into a major blood vessel

Side Effect

Direct intracellular damage by initiating radical chain reactions that damage intracellular membranes and mitochondria

Tissue-dependent local-regional inflammatory reaction

Photosensitivity

Photosensitivity

Duration is at least 30 days Reactions are similar to sunburns Incidence of photosensitivity reactions is variableSkin sensitivity– Sun burn– Redness– Swelling

Case Experience in SKH74 y/o female chronic cough for several yearsKSMUH revealed endotracheal tumor r/o adenoid cystic carcinma

2005-9-9

2005-9-9

Admission bronchoscopy

Biopsy pathology confirm adenoid cystic carcinoma

2005-9-16

Nd-YAG laser to move most of the tumor

2005-9-22

Second look over the tumor: seems to have growth

2005-9-28 IV drip Potophrin

2005-9-30 First time PDT

2005-10-3 Second look the effect of the PDT

Partial necrosis of the tumor

2005-10-5 Further debulking of the tumor with Nd

YAG laser + 2nd time of PDT was performed

2005-10-20 2 weeks later following-up

2005-12-22

3 months later following-up

Photodynamic Diagnosis PDD

5 ALAAuto-fluorescence

Early Stage Malignancy Detection

Biopsy: Gold StandardEpithelium dysplasia and in-situ carcinoma change: ultimately leading to invasive carcinoma in a variable period of time Dysplasia and in-situ carcinoma are not detected by white-light brnchoscopyInvasive lung cancer cure rates are below 15%Potential for curing in-situ carcinoma or micro-invasive cancer is 100%Local therapeutic method such as PDT can be usedChemical agents can be used to prevent or revert the progression of the carcinogenic process

Photodynamic Diagnosis

Porphyrin derivatives: HPD, 5-ALA– Blue light region Fluorescence – Red light region Phototoxicity 利用這種性可以發現腫瘤

Hayata 及 Kato 醫師發展出支氣管鏡光動力刀診斷及治療

自體螢光反應人體內有一些內生性光反應物質，不須額外給予藥物，特定波長光照射後會誘發螢光反應螢光非常微弱，須利用特殊影像系統才能發現，可應用於內視鏡診斷異常病灶

基本原理 Fluorochromes: Tissue –inherent compounds capable of fluorescenceOrgans contain diffenrent concentrations of these fluorochromes giving rise to an “organ-specific” pattern.Known fluorochromes include: – Elastin, – Collagen, – Porphyrin, and various derivatives– Tryptophan and various derivatives– Flavines and various derivatives

Endogenous Fluorochromes

1. Induced in the submucosa,2. Modulated through different effects and3. Made visible through special observation technique.

Autofluorescence is ...

White Light Imaging

No tumor visibleNo tumor visible

Fluorescence Illumination

D-Light AFD-Light AF

Only Blue -Only Blue -no tumor visibleno tumor visible

Autofluorescence

D-Light AFD-Light AF

AF FiberscopeAF Fiberscope

PDD/AF CameraPDD/AF Camera T/N contrast - T/N contrast - tumor visibletumor visible

Fluorescence bronchoscopy: effect of observation filter

Without filter With filter

White light

Blue light

Milde Dysplasie

Carcinoma in situ

LIFE System: Olympus/Xillix

D-Light AF: Karl StorzD-Light AF: Karl Storz

新光吳火獅紀念醫院健康管理中心 胸腔內外科 放射科 病理科　早期肺癌檢測計畫Early Lung Cancer Detection Project

報告人 : 謝義山 胸腔外科主治醫師計畫主持人：高尚志主任　呂志剛主任　　　　　　陳良光主任　黃克明主任 江俊松主任 李進成主任

肺癌篩檢計劃在體檢項目內加入 (早期肺癌檢測 ) 選項– 低放射劑量電腦斷層（ LDCT )加入國際早期肺癌篩檢計畫 I-ELCAP– 自體螢光支氣管鏡（ AF-Bronchoscopy ）

Indication:– 40 歲以上 (國內肺癌發生率從四十歲大幅增加 衛生署資料 )– 長期抽煙者– 女性有肺癌及其他癌症家族史者– COPD– Asbestoses exposure