Table 3.

Summary of the advantages and disadvantages of photodynamic-derived multimodal synergistic therapy.

Strategies	Advantages	Disadvantages	Ref.
Synergistic PDT/chemotherapy	Effective application of hypoxia-activated cytotoxic drugs Utilization of PSs with both photothermal conversion and 1O2 generation capacity Tumor recurrence reduction	Potential damage to normal tissue	[160,161]
Synergistic PDT/immunotherapy	Amplification antitumor immune response owing to PDT-triggered tumor antigen presentation Long time circulation period Immunogenic cell death for immunotherapy enhancement	Low drug release efficiency Hypoxic reactive immunosuppression Immune response triggered by accidental drug release	[162,163]
Synergistic PDT/ PTT	PSs delivery promotion through blood flow improvement Fewer adverse effect PSs delivery promotion through blood flow improvement Tumor oxygen levels elevation	Different spectra for irradiation Toxicity to body	[161,164]
Synergistic PDT/ starvation therapy	High H2O2 yield to support PDT PDT- induced cellular components disruption to assist starvation therapy	Adaptation of cancer cells to low energy supply	[142,143]
Synergistic PDT/ radiotherapy	Better penetration depths into tumor Low dose radiation Tumor recurrence prevention	Limited Energy accumulation at tumor sites Radiation therapy resistance Toxicity and side effects on normal tissues	[165,166]