Gastric Cancer Specialist in Guatemala

Gastric cancer requires specific training in digestive tumors.

Treatment for stomach and esophageal cancer depends on the tumor's characteristics. Knowing them from the start makes it possible to use the best treatments available — including options many patients never receive because they weren't tested for in time.

When should you consult Dr. Reynoso?

You were diagnosed with stomach or esophageal cancer and need a complete oncologic evaluation

Your diagnosis doesn't include HER2, PD-L1, or MSI testing

You have difficulty swallowing, weight loss, or persistent abdominal pain

Endoscopy showed a suspicious lesion and you need guidance

Your current treatment isn't working and you're looking for options

You want a second opinion before starting perioperative chemotherapy

⚡ Consultations Monday, Tuesday, and Thursday | By appointment only

15-20%

of gastric adenocarcinomas are HER2-positive — eligible for anti-HER2 therapy

UAM

specific training in digestive tumors — Universidad Autónoma de Madrid

8+

years treating gastric and esophageal cancer in Guatemala

Q600

initial consultation with molecular review and treatment plan

HER2, PD-L1, MSI. Three markers that change the treatment.

Gastric and gastroesophageal junction adenocarcinoma are classified based on molecular profile — HER2, PD-L1 expression, and MSI/MMR status. Each profile has distinct treatment options that significantly improve outcomes when identified from diagnosis.

A HER2-positive gastric tumor treated with trastuzumab plus chemotherapy has a longer median survival than a tumor without that therapy. An MSI-high tumor responds extraordinarily well to pembrolizumab. A tumor with CPS ≥5 has access to first-line immunotherapy. Without molecular testing, those options don't exist for the patient.

Gastric cancer is one of the diagnoses where the molecular profile changes the treatment the most. HER2, PD-L1, MSI — these are three tests that should be done from diagnosis, not after the first line of treatment.
Dr. Giovanni Reynoso
Warning Signs

Symptoms that shouldn't be ignored.

Gastric cancer is often diagnosed at advanced stages because early symptoms are nonspecific. Endoscopic evaluation is essential when symptoms persist.

Book your appointment

Do you identify with any of these?

A first one-hour consultation is enough to begin your workup and, if applicable, reach a clear diagnosis

When the first treatment wasn't enough

Gastric cancer progressed. And key information may be missing.

Progression in metastatic gastric cancer is common after the first line of treatment. But in many cases, progression happens in patients who never had a complete molecular profile — and who could have access to anti-HER2 therapy or immunotherapy that was never considered.

01

Gastric tumor without HER2 testing

A HER2-positive gastric adenocarcinoma treated only with standard chemotherapy, without trastuzumab, has significantly worse outcomes than one treated with the correct protocol. If HER2 wasn't tested at diagnosis, it can be tested on available tissue — and change the strategy even in the second line.

02

MSI-high gastric tumor without immunotherapy

MSI-high tumors have extraordinary responses to pembrolizumab — even in the second or third line. Without MSI testing, that option doesn't exist for the patient. Dr. Reynoso identifies these patients and treats them with the correct protocol.

03

Progression after first-line treatment with available options

Trastuzumab deruxtecan for previously treated HER2-positive cases, ramucirumab with or without paclitaxel, nivolumab as second-line therapy — there are second-line options with demonstrated benefit in advanced gastric cancer that aren't always considered.

Gastric cancer is one of the diagnoses where the molecular profile changes the treatment the most — even in the second line. Before saying there are no more options, I need to know whether HER2 and MSI were tested.
Dr. Giovanni Reynoso
Diagnostic Process

How gastric cancer is evaluated in consultation

A complete oncologic diagnosis of gastric cancer requires histology, molecular profile, staging, and resectability assessment. The first consultation with Dr. Reynoso reviews what's already complete and what's missing.

Why consult Dr. Reynoso for gastric cancer?

Specific training in digestive tumors — UAM Madrid

Dr. Reynoso completed specific training in digestive tumors at the Universidad Autónoma de Madrid — a subspecialization that translates directly into the clinical depth he brings to gastric and esophageal adenocarcinoma.

Complete molecular profile from diagnosis

HER2, PD-L1, and MSI are requested from the diagnostic biopsy — not after the first line of chemotherapy. Identifying these markers from the start allows the best available agents to be used from the beginning.

Immunotherapy available for select profiles

Pembrolizumab and nivolumab are indicated for metastatic gastric cancer based on molecular profile — CPS ≥5, MSI-high. Dr. Reynoso identifies eligible patients and treats them with the correct protocol.

Coordination with surgery and nutritional support

Gastric cancer frequently affects the patient's nutrition. Dr. Reynoso coordinates systemic treatment with surgical management and nutritional support so the patient arrives at treatment in the best possible condition.

Received a cancer diagnosis? The next step is a consultation.

First visit, second opinion, or oncologic follow-up — you deserve an oncologist who explains everything.

Coverage and Location

Medical Oncology in Guatemala City

Dr. Giovanni Reynoso - Oncólogo

Edificio Spazio, 15 avenida y 5 calle 5-50, Vista Hermosa III, Zona 15. Nivel 10, Oficina 10-01

Bonanova Health, private hospital specializing in cancer in Zona 15

Office Hours

Monday to Tuesday from 4:00 PM to 6:00 PM Thursday from 3:00 PM to 5:00 PM

Emergency Care

Dr. Reynoso does not handle emergencies. For oncologic emergencies, go to the nearest hospital.

Coverage Areas

Frequently Asked Questions

Common questions, clear answers

Still have questions? Let’s talk directly on WhatsApp for personalized answers.