Table 2.

The Advantages and Disadvantages of Combination Therapy Compared with PDT

Combination Therapy	Advantages	Disadvantages	Ref
PDT + CT	Improve safety of chemotherapy; avoid multi-drug resistance (MDR); improve overall antitumor efficacy	Unavoidable toxicity of chemotherapy drugs	[123–127]
PDT + RT	Achieve deep tumors therapy; increase the sensitivity of tumor to RD; achieve abscopal effect	Unavoidable side effects of RD	[128–131]
PDT + Starvation therapy	Amplify of therapeutic effect; suit for hypoxic tumors	Enzyme’ shortcomings, such as poor stability, short half-life and immunogenicity; the systemic toxicity of H2O2	[49,132–135]
PDT + immunotherapy	Effectively inhibit tumor recurrence and metastasis; enhance antitumor immunity	An adverse reaction caused by an overactive immune system	[90,123,136,137]