In his “Presidential Address to the Society of Surgical Oncology,” Blake Cady stated that tumor biology is the king, patient selection is the queen, and technical procedure the prince, of the kingdom. Only rarely does the prince usurp the kingdom [50]. These considerations perfectly illustrate the problem being addressing. Patient selection criteria must maintain the balance between opposing forces. On the one side is a frequently unfavorable and undoubtedly aggressive tumor biology; on the other side is a surgeon convinced that technical efforts will snatch the patient away from an ineluctable destiny. Ideal selection criteria should indicate patients for whom surgery is most likely to have a successful outcome and therefore in whom technical, organizational, and economic efforts, necessitated by these procedures, should be invested.

Research over the past few years, limited to PC from CRC, has developed a staging classification intended chiefly for preoperative use [Peritoneal Surface Disease Severity Score (PSDSS)], which analyzes separately the entity of patient symptoms, the extent of peritoneal disease (PCI), and the histopathologic tumor features (including lymphatic spread), yielding a specific score and then subdivided into four stages (Fig. 13.3) [32]. The American Society of Peritoneal Surface Malignancies conducted a retrospective review of 609 patients who underwent CRS plus HIPEC after PSDSS staging. Their findings show that the PSDSS, assessed before surgery, can define a population with a statistically high or notably low likelihood of long-term survival (Fig. 13.4) [51].

Regardless, whatever the pros and cons of one scoring system or another, the intellectual rationale for selecting patients as candidates for CRS plus HIPEC procedures never concerns the surgeon alone. The decision inevitably requires a multidisciplinary contribution involving many specialists and includes the patients themselves so as to offer an individualized treatment option. Especially important is the need to alert the medical community (medical oncologists, the message is for you) that PSM is not by definition incurable. Quite the contrary: CRS plus HIPEC offers many of these patients a real chance of cure. Only keeping these management options firmly in mind will increase the number of patients referred to expert centers for treatment, help identify patients with PSM at earlier stages and thus simplify patient selection.