An Island, an Emperor, a Tumor on St. Helena: Napoleon and Stomach Cancer

The Autopsy Report of 5 May 1821 and a Genetic Code in the Bonaparte Family Still Being Deciphered Two Centuries Later

From Waterloo to Longwood: June 1815 to May 1821

Napoleon was born on 15 August 1769 in Ajaccio, Corsica. His father, Carlo Maria Buonaparte , was a Corsican lawyer; his mother was Letizia Ramolino. He grew up as the second son in a family of eight children. In 1779, at ten years of age, he was sent to the Brienne military school in France, then to the École Militaire in Paris. As an artillery officer, he entered the service of the French Revolution (1789), and in 1804 he placed the imperial crown on his own head at Notre-Dame. Over the next eleven years, he redrew the map of Europe, established the modern legal system (1804 Code Napoléon), campaigned in Egypt, occupied Moscow and, finally, at the Battle of Waterloo on 18 June 1815 , was defeated by the combined British-Prussian forces.

On 17 October 1815, at age 46, he was exiled to St. Helena Island by British decision. This was a small volcanic island in the middle of the Atlantic Ocean, about 1.900 kilometers from the nearest mainland (Africa) and 1.300 kilometers from the nearest neighboring island. An old farmhouse called Longwood House was assigned to the emperor as his home — damp, cold and unsuitable for living. The small entourage he brought with him (Generals Bertrand and Montholon, valet Marchand, physician Dr. Barry O'Meara) dispersed over time; some were sent back to Europe. In 1819, the Bonaparte family sent the young Corsican physician Antommarchi to the emperor.

During his six years on St. Helena, Napoleon's health gradually deteriorated. Modern medical historians divide this period into five stages:

In his final weeks, Napoleon saw his condition extremely clearly. He told his loyal valet Marchand: “My father died of stomach cancer. I will die of the same disease. This is my end.” Before dying, he dictated his will, instructing Antommarchi to perform an autopsy: “I want you to perform my autopsy after my death. No British physician other than Dr. Arnott is to touch my body."

This sentence matters: an autopsy on his own body after death was something that Napoleon, unlike Maria Theresa, wanted. The reasons were probably twofold: first, to establish how real the history of stomach cancer in his family was; second, to document claims that would circulate in Europe for years that the conditions of exile had killed him. Ultimately, he largely achieved both aims.

Two Reports, Sixteen Witnesses, One Historical Document

The autopsy took place the day after his death in a temporary autopsy room created from the billiard room at Longwood House. Sixteen people were present: the emperor's companions in exile, his servants, and Thomas Shortt (head), Archibald Arnott, Charles Mitchell, Francis Burton and Matthew Livingstone from the British medical delegation. The young Corsican physician Dr. Antommarchi led the procedure — he had been selected because he had studied under the famous anatomy professor Giuseppe Mascagni (1755-1815) at the University of Siena.

Two separate autopsy reports were subsequently written: one by Antommarchi (an expanded version published in his memoirs in 1825), the other by the British physicians. The two reports largely agree on gastric pathology; the main differences concern findings in other organs (especially the lungs and liver) and details Antommarchi added later. Modern historian Lugli and colleagues (2007, 2021) have shown that Antommarchi's 1825 publication differed substantially from his initial report and that some passages appear to have been taken from a French medical journal dated 1823 — raising suspicion that Antommarchi later embellished his report for his reputation.

The shared — and reliable — findings are as follows:

The direct cause of death appears to have been chronic gastrointestinal bleeding and the resulting severe anemia rather than the perforation — melena and hematemesis in the final week support this. Tumor erosion into vascular structures and persistent bleeding explain Napoleon's pallor, tachycardia and weakness in his final weeks.

Forshufvud 1961, Hindmarsh 2008, Lugli 2007 — A Modern Forensic Inquiry

Although the autopsy reports clearly indicate stomach cancer, Napoleon's cause of death remained disputed throughout the 19th century. A theory attracted international attention particularly after the 1960s: arsenic poisoning.

In 1961, Swedish dentist Sten Forshufvud compared symptoms in the memoirs of Napoleon's loyal St. Helena valet Marchand (sweating, muscle twitching, thirst, jaundice) with the classic symptoms of arsenic poisoning. Analyzing a lock of Napoleon's hair cut in 1816, Forshufvud found an arsenic concentration far above normal (10.38 µg/g, normal approximately 0.5-1 µg/g). The result: Nature published a paper in 1961 in which Forshufvud claimed that Napoleon had died from deliberate arsenic poisoning. Comte Charles de Montholon (his companion in exile) was named as a possible suspect.

This theory filled popular history books and documentaries for the next 50 years. By the 21st century, however, modern forensic toxicology had largely refuted the hypothesis:

• Hindmarsh, Corso and colleagues, 2008: Researchers at the University of Pavia (Italy) analyzed samples of Napoleon's hair from different years (1804 presidency, 1814 exile on Elba, 1821 death). The result: arsenic levels were high in every period, and were even higher in the years before St. Helena. Napoleon had therefore lived with high arsenic levels for years — this was not poisoning but a consequence of the period's chronic arsenic exposure . In the early 19th century, arsenic reached high levels in most of the population through house paints, curtains, medicines, food preservatives and disinfectants.
• Lugli and colleagues, 2007, Nat Clin Pract Gastroenterol Hepatol: Reassessment of autopsy findings through the eyes of a modern pathologist. Tumor size, stage, perforation, signs of chronic bleeding and clinical course — all are consistent with advanced stomach cancer rather than chronic arsenic poisoning. Arsenic is the noise in this story, rather than its cause.
• Lugli, Carneiro and colleagues, 2021, Virchows Archiv: An assessment by an international consortium of pathologists for the 200th anniversary of his death (Bern, Porto, Paris, Toronto). Conclusion: Advanced gastric adenocarcinoma, with gastric perforation and death from chronic bleeding. The arsenic theory is closed.

This is an important teaching point in medical history: the autopsy report of the 1820s — clinical observations made without modern instruments or a microscope — had provided the correct diagnosis. The “conspiracy theory” alternative diagnosis that became fashionable 140 years later was much more sensational but wrong. In the history of science, the simple, correct answer often loses to the sensational, wrong answer — but always returns in the long run.

Seven Family Members Who Died of Stomach Cancer Across Three Generations

Napoleon's death was not the only case of stomach cancer in his family. On the contrary, the Bonaparte family carries one of the most extraordinary clusters of stomach cancer documented in medical history. The table below shows familial cases of stomach cancer derived from existing historical records:

Seven cases across three generations, some before age 50 — this moves beyond coincidence. In terms of modern family-history screening criteria (International Gastric Cancer Linkage Consortium guidelines updated in 1999, 2010 and 2020), the Bonaparte family largely meets the clinical diagnostic criteria for hereditary diffuse gastric cancer (HDGC).

An E-Cadherin Mutation That Settled in Corsica in the 1500s

In 1998, through a molecular study of a cluster of diffuse gastric cancer at young ages and lobular breast cancer in a Māori family from New Zealand, a germline (inherited) mutation in the CDH1 gene (E-cadherin) was identified. CDH1 is a tumor suppressor gene located on chromosome 16q22.1; its product, E-cadherin, enables epithelial cells to adhere to each other. In an individual carrying a mutation on one side (heterozygous), when the cell loses the other allele through a subsequently acquired (somatic) mutation — that is, when two hits have occurred, in accordance with Knudson's 1971 hypothesis (to be covered on Day 155) — cancer development begins.

HDGC syndrome is inherited in an autosomal dominant pattern: each child of a parent carrying a CDH1 mutation has a %50 risk of inheriting it. In mutation carriers, the lifetime risk of diffuse-type stomach cancer reaches %70 in men and %56 in women; women additionally have a lobular breast cancer risk of approximately %42.

The HDGC hypothesis in the Bonaparte family was first proposed by Lugli and colleagues in 2007. In subsequent years, Carneiro and other medical historians supported it. If the hypothesis is correct — and it seems quite plausible in light of today's clinical criteria — Carlo Bonaparte, as a CDH1 mutation carrier in the family, may have passed the mutation to at least four of his seven children (Napoleon, Pauline, Caroline, Lucien). This is part of the seven-generation biological legacy of the Buonaparte family, who migrated from Liguria to Corsica in the 16th century.

A Modern Oncological Approach for a Bonaparte Diagnosed with HDGC

What would happen if modern medicine could see Napoleon in 2026? This exercise is educational rather than historical — it makes today's management of hereditary stomach cancer tangible for patients with a family history:

First step — Family history and genetic testing. A seven-year-old Corsican child whose father had died at age 38 of a “stomach illness” would have been referred to a modern genetic counseling center as a son of that family. CDH1 germline mutation testing (Sanger sequencing or an NGS panel) would have been performed early. If carrier status were confirmed:

Second step — Active surveillance and prophylactic gastrectomy. Under current international guidelines (IGCLC 2020 consensus, NCCN 2024), for CDH1 mutation carriers between ages 18-25, prophylactic total gastrectomyis recommended for discussion. This is because HDGC is difficult to detect early by endoscopy — diffuse-type tumors grow beneath the mucosa in an infiltrative pattern resembling “linitis plastica,” without classic endoscopic findings. Where prophylactic gastrectomy is declined, endoscopic follow-up every 6 months + a biopsy regimen are used.

Third step — Breast screening for female relatives. Female CDH1 carriers such as Pauline and Caroline Bonaparte would have been managed with annual mammography + MRI + discussion of prophylactic mastectomy.

Fourth step — Treatment: If cancer has developed by the time of diagnosis. Napoleon presenting in 2026 — with advanced diffuse gastric adenocarcinoma, perforation and chronic bleeding at age 51 — would still be a difficult scenario today. The modern approach, however: emergency support (transfusion, antibiotics, closure of the perforation), neoadjuvant treatment (the MATTERHORN protocol — perioperative FLOT + durvalumab, if resectable), genomic profiling (HER2, PD-L1, CLDN18.2, FGFR2, MSI status) and total gastrectomy in selected cases. Five-year survival for resectable advanced HDGC remains around %25-35 today — much better than in 1821, but still a disease with an unpromising outlook, even if not utterly hopeless.

This article is Day 72 of the Cancer History in 365 Days Series. The hypothesis of hereditary stomach cancer in the Bonaparte family will be explored in a broader framework on Days 160-166 of the hereditary cancer syndromes series (Broca, Warthin, Lynch, Li-Fraumeni, von Hippel-Lindau, Mary-Claire King and BRCA). The modern MATTERHORN protocol and the current landscape of stomach cancer treatment will be covered on Day 316 and thereafter. The article was prepared from a popular historical perspective and does not provide medical treatment guidance.