Mini Review
Volume 10 Issue 1 - January 2018
DOI: 10.19080/OROAJ.2018.10.555776
Ortho & Rheum Open Access J
Copyright © All rights are reserved by Marcos B Paiva
Recent Development of Laser Photo-Chemotherapy
(LPC) for Bone Tumors
Renan V Brito
1
, Marcel N Palumbo
1
, Joao C Ribeiro
1
and Onivaldo Cervantes
1
and Marcos B Paiva
2
1
Federal University of Sao Paulo, Brazil
2
Laser Chemotherapy Program, University of California, Los Angeles
Submission: December 18, 2017; Published: January 12, 2018
*Corresponding author: Marcos B. Paiva, Department of Surgery, University of California, Los Angeles, USA, Email:
Mini Review
Photodynamic therapies (PDT) have become increasingly
popular in the adjuvant treatment of different tumor entities
[1]. Chemotherapeutic agents, such as cisplatin may be used
in combination with laser-induced thermal therapy (LITT) in
an improvement to PDT, known as laser photo chemotherapy
(LPC) [1,2]. Based on recent reports on the application of laser
photo chemotherapy (LPC) on malignant bone cells under
chemotherapeutic conditions with cisplatin or zolendronic
acid, the authors feel compelled to describe in this mini-review
some relevant aspects of such combined therapy as a potential
therapeutic strategy for osteosarcoma [3].
Chemotherapy is regularly used for treating Ewing sarcoma
and osteosarcoma, but it isn’t often used for other bone cancers,
like chordomas and chondrosarcomas, because they aren’t
very sensitive to chemo [4]. However, it can be useful for some
special types of chondrosarcoma, like the dedifferentiated and
mesenchymal lineag [3,4]. Anti-cancer agents are sometimes
used for bone cancer that has spread through the bloodstream
to the lungs and/or other organs [5]. The drugs mainly used
for this condition include: Doxorubicin (Adriamycin®),
Cisplatin, Carboplatin, Etoposide (VP-16), Ifosfamide (Ifex®),
Cyclophosphamide (Cytoxan®), Methotrexate and Vincristine
(Oncovin®) [3,5]. In this regard, a number of investigators
have shown that some of the above anti-cancer agents are likely
candidates for light and or heat activation in cancer cells, as
laser photo chemotherapy (LPC) has been consistently used for
treatment of retinoblastoma since 1996 [3,6-8].
The propensity for survivors of heritable retinoblastoma to
develop second primary osteosarcomas at substantially greater
frequency than either the general population or survivors
of nonheritable retinoblastoma is well known [9,10]. There
is some molecular genetic evidence that the development of
these two disparate tumor types involves specific somatic
loss of constitutional heterozygosity for the region of human
chromosome 13 that includes the RB1 locus [11]. In regards
to chemotherapy a number of investigators have shown that
anthracyclines and cis-platinum are likely candidates for light
or heat activation in cancer cells [1,2,12]. In this sense, Heyman
et al. [3] have recently reported a significant decrease of cell
bioviability and histomorphological alterations suggestive of
higher apoptical activity in osteosarcoma cell lines (Saos-2)
treated by cisplatin and zolendronic acid followed by diode
laser irradiation, when compared with non-irradiated cells.
Therefore, LPC outcomes for retinoblastoma may suggest that
a conceptual approach towards osteosarcoma treatment may be
possible based on recent clinical studies on combined therapy
[12,13-18].
Photo chemotherapy with lasers is an alternative therapy
which consists of using a monochromatic light delivered via
external irradiation or via interstitial fiber optics to enhance
the ``killing`` threshold in tumors containing light and/or
heat-sensitive anticancer agents [12]. The development of
photoactivatable pro-drugs of platinum-based antitumor agents
is aimed at increasing the selectivity and thereby lowering
toxicity of this important class of antitumor drugs [19-21]. Hence,
laser photo chemotherapy explores three distinct mechanisms
of antitumor action: direct anti-cancer effect
i. Additionally: thermal
ii. Light sensitizer
iii. Effects [1,2,22].
These drugs may be injected intravenously at concentrations
lower than normal chemotherapeutic levels, or at higher
intratumor doses reducing systemic toxicity while enhancing
local tumoricidal effects by laser photoactivation in situ
[2,23,24]. Anthracyclines have also been identified that have
greater photosensitization potential than daunomyucin [25].
With all the supporting evidence of translational and clinical
protocols laser photo chemotherapy has established itself as
an alternative treatment for retinoblastoma [18,26,27]. Most of
Ortho & Rheum Open Access J 10(1): OROAJ.MS.ID.555776 (2018) 001
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