Multimodality treatment strategies have changed prognosis of peritoneal metastases

Table 1 Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy median survival, related to the tumor entities and study type

Primitive tumor origin	Study type	Median survival (mo)
Colorectal	Randomized clinical trials	22.3[35]
	Single center experience	33[53], 34.7[45]
	Systematic reviews	13-29[54]
	Multi-institutional studies	33[52]
Gastric	Randomized clinical trials	11.3[46], 11[47]
Pseudomyxoma peritonei	Single center experience	104[53]
	Multi-institutional studies	130[52]
Ovarian	Multi-institutional studies	35.4-45.7[51]
	Systematic reviews	22-54[55]
Malignant peritoneal mesothelioma	Systematic reviews	34-92[56]

Table 2 Key aspects and peritoneal metastases model in the evolution of multimodal treatment

Period	PM treatment	Key aspects	PM model
All the period	“Conventional” systemic chemotherapy	Significant lower survival for PM vs other type of metastases	Colo-rectal
1950-1980	“Dedicated” intraperitoneal treatment - Palliative treatment	The basis for developing further cytostatic drugs	Malignant ascites
1980-2000	“Dedicated” intraperitoneal treatment - Multimodal radical treatment	Regional intraperitoneal normothermic and hyperthermic chemotherapy	Appendicular
		Peritonectomy procedures
		Define PCI and CCRS
2000-2010	Multimodal radical treatment - confirmation, aspects, patient selection, controversies	Significant higher survival vs palliative surgery and diverse systemic chemotherapy regimes	Colo-rectal
		Acceptable morbidity and mortality, no significant risk for medical team	Appendicular
		Respect de learning curve	Pseudomyxoma peritonei
		High costs	Malignant peritoneal mesothelioma
		Define the prognostic factors	Gastric
		Position of oncologists	Ovarian
		Comparison with hepatic metastases	PM with hepatic metastases
2010-2014	Multimodal treatment – research pathways	PM prophylaxis	High-risk patients for developing PM
		Laparoscopic HIPEC	Recurrent PM
		Integration of chemotherapy with surgery
		Extension of CRS

PM: Peritoneal metastases; CCRS: Completeness of cytoreduction score; CRS-HIPEC: Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy; PCI: Peritoneal cancer index.