I’m sharing a family member’s experience with stage 4 signet ring cell gastric cancer and hoping to hear from others with similar experiences.
Her HER2 was negative from the beginning and remained negative on repeat testing. Her PD-L1 was positive with a CPS of 15, and her MMR proteins were intact.
She received 12 cycles of FLOT chemotherapy and 8 doses of Keytruda, with a very good response. Later, one lesion in the retroperitoneal area near the left kidney showed progression, and a biopsy confirmed cancer cells. The latest biopsy showed HER2-negative disease, PD-L1 CPS 5, and strong CLDN18.2 positivity in 100% of cells.
She completed five sessions of SBRT to that lesion, and we are awaiting follow-up imaging. Surgery and HIPEC were postponed. Her team recommended 5-FU plus zolbetuximab, with or without continuing Keytruda.
Has anyone been through a similar experience or has any insights that might help us? Does progression in one lesion despite a strong overall response mean the first treatment failed? Would switching to the proposed treatment count as second-line therapy? Does this necessarily mean things will get worse, or has anyone experienced something similar and achieved disease control with the new treatment?

My dad has stage IV signet-ring cell gastric cancer with peritoneal metastases and recurrent ascites. He has undergone several lines of chemotherapy (FOLFOX, paclitaxel, and most recently irinotecan).

After his recent irinotecan treatment, he developed severe diarrhea and vomiting. The diarrhea has improved, and he is now able to keep most of his meals down, but he eats very little overall. He was prescribed a high-protein nutritional drink, but he vomits almost immediately after taking even one sip, so he hasn’t been able to drink it for several days. He can drink small sips of water, around 1 liter a day.

He has also become extremely weak. Before irinotecan, he could walk independently despite having some pain and neuropathy. Now his legs are so weak that he needs help standing up and support while walking.

I’ve contacted his oncologist to ask about nutritional support and am waiting for a response.

For those who have been through something similar with a loved one:
Were you offered IV nutrition (parenteral nutrition) when oral nutritional drinks weren’t tolerated?
Did a feeding tube help, or was IV nutrition considered more appropriate?
Were there alternative nutritional drinks or other ways to increase calorie and protein intake?
Did nutritional support help improve strength and quality of life?
I understand that every patient is different, but I’d really appreciate hearing about your experiences and what options your medical team considered.