Nearly all academic oncologists in Israel have had fellowship training at medical centers in the United States. Most look back wistfully on the people they met and the knowledge they acquired abroad. When they get together to reminisce, there is good-natured bickering about the quality of their respective American institutions, but there is uniform agreement that one of the highlights of the years they spent in the United States was the celebration of Thanksgiving. And why not? It’s a long weekend of copious eating that displays a unique national character that, unlike Christmas, transcends religion and, unlike Super Bowl Sunday, rises above cultural predilection. Lately, though, the concept of thanksgiving has come to acquire new resonance among oncologists in Israel.The Hebrew phrase seudat-hodayah—“thanksgiving feast”—has inserted itself into the lexicon of both cancer doctors and patients here over the past seven or eight years. A seudat-hodayah is a cancer survivor’s celebration of having beaten the disease. I am invited to participate in them not only in November but throughout the year.My first invitation was hand-delivered by a hulking disciple of a 66-year-old grand master of a Hasidic dynasty. Only a week earlier, I had finished treating the sage with cranial-radiation therapy for an aggressive brain tumor. Although I make very few house calls, I quickly resolved to adopt a new rule of thumb: When summoned by the consigliere of a rabbinical godfather, best not to refuse.Alighting from the limousine sent to fetch me, I was surprised to discover that we had arrived not at the rabbi’s home but rather at a nearby synagogue. I was escorted to a podium, looking out over a sea of black. Nearly 500 admiring followers dressed in formal topcoats and fedoras had gathered in a cavernous sanctuary in the city of Bnai Brak to count their blessings and salute “the man who had saved their spiritual leader.” That was presumed to be me. I don’t remember precisely what I said during my impromptu remarks, but I do recall that I did not emphasize that the rabbi was unlikely to survive for more than one year. Instead, I elected to take part in their joy and to revel in my brief tenure as a rock star.My second invitation to a thanksgiving feast arrived 10 months later. On this occasion, the patient himself requested that I join in celebrating the one-year anniversary of his completion of thoracic irradiation for lung cancer. This patient, a self-described flower child, boasted that he’d first had to survive Woodstock before he could survive lung cancer. Once again, the seudat-hodayah emphasized a sincere appreciation for both the care provided and the patient’s benefits in quantity and quality of life. The featured activity at that particular thanksgiving feast involved smoking expensive blends of marijuana (the nonmedical variety) and sharing an array of decorative bongs. I took a less active role at this celebration.Nowadays, I am invited to a seudat-hodayah roughly every six weeks. The actual number is irrelevant, but what is reassuring is that I attend more thanksgiving celebrations for my patients than funerals. Festivities often include singing folk songs or a poetry reading along with the consumption of abundant quantities of ethnocentric comfort food: noodle kugel in homes that trace their ancestry to obscure Ashkenazic hamlets of Eastern Europe, couscous among families with a Sephardic or Mizrahi heritage. The overriding theme at all these affairs is gratitude.Clearly, the seudat-hodayah is hip in Israel. The question most frequently asked by caregivers who wish to organize such a party is not whether to do it but when to do it. Indeed, a large number of family members want me to countenance, or even bless the propriety of embarking on such festivities at the desired juncture. In order to better answer these inquiries, I set out to identify the source of the seudat-hodayah in Jewish tradition.If consensus exists, the origin of the custom may be found in Genesis: “And Abraham held a great feast on the day Isaac was weaned.” But there is controversy embedded in the scriptural passage. Was Abraham celebrating a specific developmental milestone (that is, the literal end of Sara breastfeeding Isaac), or was something more conceptual going on? In the ancient world, infant mortality was presumably sky high. So, could it be that weaning was actually a surrogate for Isaac’s authenticated survival of the only other major event that he experienced (that is, circumcision)? Applied to oncology patients, this question becomes: Is it proper to celebrate immediately after attaining a milestone (e.g., completion of treatment), or must one wait for a period of time to be certain that there is cause for celebration (e.g., the classical five-year-survival endpoint)?Having considered that question on multiple occasions, for me the answer is now clear. Feasts of thanksgiving—little “t” or upper case—can be either an outgrowth of gratitude, as in emerging Israeli custom, or can inculcate gratitude, as with the American holiday. It is unfortunate that gratitude is in such short supply in modern societies, given its status as a prerequisite toward the attainment of happiness. For me, the correct time for patients to celebrate in thanksgiving has nothing to do with reaching conventional watermarks for oncologic cure but everything to do with feeling the need to express that sublime state of appreciation that we call gratitude.To this day, even my closest friends struggle to understand why I would select a profession that orients itself around people diagnosed with malignant disease. But without these heroic patients, I would be nothing less than an ingrate. Repeatedly, cancer patients have taught me to value the intangibles that I tend to take for granted, especially good friends and good health. On this year’s Thanksgiving—the American one, with a capital T—between the football games, the jokes about Uncle Harvey, and the fight over the last piece of pie, may we remind ourselves of the wealth of things that we have to be thankful for in our lives.Benjamin W. Corn is professor and chairman of the Institute of Radiotherapy at Tel Aviv Medical Center and a co-founder of the NGO Life’s Door.