HIPEC FOR
GASTRIC CANCER
Gastric cancer with peritoneal metastases is the most aggressive peritoneal surface malignancy. Selected patients with limited peritoneal disease โ particularly in Asian centres with high gastric cancer volume โ achieve meaningful survival benefit with gastrectomy and peritonectomy combined with intraperitoneal chemotherapy.
analyticsAt a Glance
- check_circlePeritoneal metastases occur in 15โ20% of gastric cancers at diagnosis โ and are the leading cause of death in the disease
- check_circleMedian OS without treatment: 3โ6 months; with best systemic therapy: 8โ14 months; with CRS-HIPEC (selected cases): 15โ24 months
- check_circlePatient selection is strict โ PCI โค6โ12, no signet ring cell predominance, and complete cytoreduction achievable
- check_circleJapanese and Korean data provide the strongest evidence; Chinese centres are experienced with this approach
Why Gastric Peritoneal Metastases Are So Difficult to Treat
Gastric cancer with peritoneal metastases represents the most lethal pattern of gastric cancer spread. Unlike liver or lung metastases from gastric cancer โ which can occasionally be resected โ peritoneal disease has historically been considered an absolute contraindication to curative surgery. The prognosis with systemic chemotherapy alone is 8โ14 months at best.
โGastric peritoneal carcinomatosis sits at the intersection of two difficult clinical problems: a cancer with aggressive biology and a metastatic pattern that resists systemic chemotherapy. Surgery in carefully selected patients is the only approach that meaningfully changes survival.โ
Why Systemic Chemotherapy Fails
The peritoneal-plasma barrier limits IV chemotherapy penetration into peritoneal deposits. In gastric cancer, this barrier is compounded by the aggressive biology โ signet ring cells, poorly differentiated histology, and microsatellite-stable tumours that are resistant to both chemotherapy and immunotherapy in the majority of cases. The net effect is that systemic therapy provides palliation but rarely achieves meaningful tumour reduction at peritoneal sites.
The Asian Experience: Why CRS-HIPEC Data Come Primarily from Japan and China
Gastric cancer is 4โ5ร more common in East Asia than in the West โ making Japanese, Korean, and Chinese surgical oncology centres the world's highest-volume gastric cancer programmes. The Asian experience with gastrectomy combined with intraperitoneal chemotherapy is more extensive than any Western programme, and most published CRS-HIPEC data for gastric peritoneal metastases originate from these centres.
Clinical Evidence for CRS-HIPEC in Gastric Cancer
The following data represent the key published trials and series evaluating intraperitoneal chemotherapy combined with gastrectomy for gastric peritoneal metastases.
PHOENIX-GC Trial (Japan, 2018): IP Paclitaxel + Systemic Chemotherapy
Source: Ishigami H et al., J Clin Oncol. 2018;36(19):1922โ1929. IP paclitaxel + S-1/IV paclitaxel vs S-1/IV cisplatin
- Median OS: IP paclitaxel arm17.7 mo
- Median OS: systemic chemo arm15.2 mo
- 1-year OS: IP paclitaxel arm67%
CRS + HIPEC for Gastric PC โ Asian Retrospective Series
Pooled from Yang et al. (China) and Yonemura et al. (Japan) series; strict patient selection PCI โค12
- Median OS: CRS-HIPEC, PCI โค624 mo
- Median OS: CRS-HIPEC, PCI 7โ1217 mo
- Median OS: systemic chemo, matched PCI10 mo
Patient Selection for CRS-HIPEC in Gastric Cancer
Gastric cancer requires the strictest patient selection of all peritoneal malignancies for CRS-HIPEC โ the narrow benefit window demands careful case-by-case review at specialist MDT.
| Criterion | Required for Consideration | Excludes from Surgery |
|---|---|---|
| PCI | โค6 (strict); โค12 at experienced centres | >12 โ complete cytoreduction rarely achievable; high operative risk for minimal benefit |
| Histology | Intestinal-type adenocarcinoma preferred | Signet ring cell >50% โ extremely poor prognosis even with CC-0; most centres decline |
| Cytology | Negative peritoneal cytology (P0Cy0) or limited positive cytology (P0Cy1) โ some centres | Macroscopic peritoneal disease with positive cytology (P1) โ discuss at specialist MDT |
| HER2 status | Does not affect eligibility โ HER2+ treated with trastuzumab adjuvantly | N/A |
| Nutritional status | Serum albumin โฅ3.0 g/dL; BMI โฅ18.5 | Severe cachexia โ major complication and mortality risk that substantially outweighs benefit |
| Prior chemotherapy | Responding disease after FLOT, FOLFOX, or S-1/cisplatin | Rapidly progressive disease or primary platinum resistance |
| Performance status | ECOG 0โ1 | ECOG 2+ โ major operative risk without established survival benefit |
Benefits vs Limitations: Honest Assessment for Gastric Cancer Patients
Gastric peritoneal metastases require the most candid benefit-risk conversation in peritoneal oncology. The potential survival benefit is real but modest, and the surgical risk is significant.
Potential Benefits
- 7โ14 months median OS improvement in selected patientsFor patients with PCI โค6, intestinal histology, and complete cytoreduction, published series show median OS of 20โ24 months compared to 10โ12 months with systemic chemotherapy alone.
- Prevents fatal complications of peritoneal diseaseMalignant bowel obstruction โ the most devastating complication of gastric peritoneal carcinomatosis โ can be prevented or significantly delayed by complete peritonectomy.
- Option for conversion surgery after chemotherapy responsePatients who achieve significant response to FLOT or FOLFOX โ including peritoneal cytology conversion from positive to negative โ may be candidates for conversion surgery with HIPEC.
- Only treatment with potential for long-term survivalNo systemic regimen achieves 2-year survival in gastric peritoneal metastases without surgical intervention. CRS-HIPEC, in optimal candidates, offers the only realistic path to 24+ months survival.
Significant Limitations
- Very poor outcomes for most patientsThe majority of gastric peritoneal metastasis patients โ those with PCI >12, signet ring histology, or poor performance status โ do not meet criteria. For them, palliative systemic therapy is the appropriate approach.
- High operative morbidity and mortality riskMajor complication rates of 30โ40% and operative mortality of 3โ5% at high-volume centres โ higher than for colorectal or ovarian CRS-HIPEC โ reflect the complexity and physiological burden of this surgery.
- No Level 1 evidence from Western RCTsThe strongest gastric HIPEC data come from Asian series and the PHOENIX-GC trial of IP chemotherapy (not HIPEC). Western RCT data are limited and do not yet provide the same evidence level as for ovarian cancer.
- Signet ring cell histology carries very poor prognosisSignet ring cell carcinoma โ common in young patients and women โ responds poorly to all therapies including CRS-HIPEC. Most specialist centres decline surgery for predominantly signet ring cell disease.
More from the Peritoneal Oncology Resource Library
Continue exploring CRS-HIPEC โ from patient selection to the full recovery guide and access pathways.
Frequently Asked Questions
Common questions from gastric cancer patients with peritoneal spread.
About HIPEC for Gastric Cancer
My gastric cancer is HER2-positive with peritoneal metastases โ does trastuzumab replace HIPEC?
Trastuzumab and HIPEC are not mutually exclusive. HER2-targeted therapy โ trastuzumab ยฑ pertuzumab or trastuzumab deruxtecan โ provides systemic disease control and should be part of the treatment plan for HER2-positive gastric cancer. However, intraperitoneal chemotherapy during HIPEC delivers drugs directly to peritoneal deposits at concentrations that systemic trastuzumab cannot match. In principle, HER2-positive patients with limited peritoneal disease meeting other CRS-HIPEC criteria could benefit from the locoregional surgical approach in addition to HER2-targeted therapy โ this is a specialist MDT discussion, not a binary choice.
I am Japanese โ should I seek treatment in Japan or would Chinese centres be comparable?
Japan has the world's highest gastric cancer volume and some of the most experienced gastric oncology programmes globally. Chinese academic centres โ particularly in Shanghai, Beijing, and Guangzhou โ also have very high gastric cancer volume and extensive experience with gastrectomy and peritoneal disease management. From a volume and experience perspective, both are appropriate. The practical considerations โ travel cost, language, visa, and cultural familiarity โ will likely be more similar between Japan and China than between either and a Western centre. CancerFax can help you navigate options in China if Japan is not accessible for your specific circumstances.
How CancerFax Helps
CancerFax is a specialist cancer access and patient-navigation platform. We help patients and families understand their options, organise medical records, coordinate hospital communication, and support cross-border treatment planning where appropriate.
We help collect and organise reports, scans, pathology, biomarker results, and treatment history for structured case review.
We communicate with hospitals or trial teams to assess whether a case may be suitable for further screening.
We support appointment coordination, document submission, translation, and direct communication with international departments.
For international patients, we help with practical coordination โ travel planning, hospital admission guidance, and local support.
If this option is not suitable, we help explore other relevant treatments, clinical trials, or advanced care pathways.
From inquiry through to follow-up, our coordinators provide a single point of contact for the family.
CancerFax does not guarantee treatment access, eligibility, or clinical outcome. Our role is to help patients access accurate information, structured review, and appropriate specialist pathways.
Explore Options for Gastric Cancer with Peritoneal Spread
CancerFax reviews your PCI, histology, HER2 status, and prior therapy to assess whether limited gastric peritoneal disease is amenable to a surgical approach โ and connects you with gastric oncology teams at Chinese and Indian centres experienced in this technically demanding combination.
This content is for informational purposes only and does not constitute medical advice. Always consult a qualified oncologist before making treatment decisions.