From the Guidelines
The Peritoneal Carcinomatosis Index (PCI) score is calculated by dividing the abdomen into 13 regions and assigning a lesion size score to each region, then summing these scores for a total ranging from 0 to 39, as described in the most recent study 1. The 13 regions include 9 abdominopelvic regions (right upper, right flank, right lower, epigastrium, central, left lower, left flank, left upper, and pelvis) and 4 small bowel regions (upper jejunum, lower jejunum, upper ileum, and lower ileum). For each region, assign a score of 0 if no tumor is visible, 1 for tumor nodules up to 0.5 cm, 2 for nodules between 0.5-5 cm, and 3 for nodules larger than 5 cm or confluent tumors. This scoring is typically done during surgical exploration or laparoscopy, though CT scans can provide preliminary estimates, as supported by previous guidelines 1. The PCI score helps determine the extent of peritoneal disease and guides treatment decisions, particularly regarding the feasibility and potential benefit of cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC), with higher scores generally indicating more extensive disease and may suggest poorer prognosis or limited benefit from surgical intervention, though specific cutoff values vary by cancer type 1. Some key points to consider when calculating the PCI score include:
- The importance of accurate lesion size assessment, as it directly impacts the PCI score and subsequent treatment decisions 1.
- The role of CT scans in providing preliminary estimates of the PCI score, which can inform surgical planning and patient selection for HIPEC 1.
- The need for a multidisciplinary approach to managing peritoneal carcinomatosis, incorporating expertise from surgery, oncology, and radiology to optimize patient outcomes 1.
From the Research
Peritoneal Carcinomatosis Index Score Calculation
The peritoneal carcinomatosis index (PCI) score is used to assess the extent of peritoneal metastases in patients with peritoneal carcinomatosis. The calculation of the PCI score is based on the distribution and size of the tumor nodules in the abdominal cavity.
- The PCI score ranges from 1 to 39, with higher scores indicating more extensive disease 2.
- The score is calculated by evaluating the size and distribution of tumor nodules in 13 regions of the abdominal cavity, including the right and left upper and lower abdominal regions, the pelvis, and the small bowel and its mesentery 3.
- Each region is assigned a score from 0 to 3, based on the size of the tumor nodules: 0 (no tumor), 1 (tumor nodules < 0.5 cm), 2 (tumor nodules 0.5-5 cm), and 3 (tumor nodules > 5 cm) 2.
- The scores for each region are then added together to give a total PCI score, which can range from 0 to 39 2.
Clinical Significance of PCI Score
The PCI score is an important prognostic factor in patients with peritoneal carcinomatosis, as it can help predict the likelihood of successful treatment with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) 2, 4.