The latest work also sounds a cautionary note against underestimating a body part or dismissing it as vestigial, expendable or past its prime. In an accompanying essay, Ting Jia and Eric G. Pamer of Memorial Sloan-Kettering Cancer Center admit that “the spleen lacks the gravitas of neighboring organs” like the liver or the stomach “because we can survive without it.”

Image Credit... Jonathon Rosen

Spleens can rupture during contact sports, say, or in a motorcycle accident, at which point surgeons have no choice.

“It’s such a vascularized organ, and the risk of big-time hemorrhaging is so great, that if the spleen ruptures, it’s a surgical emergency,” said James N. George, a hematologist with the University of Oklahoma Health Sciences Center. “You have to remove it.”

The new findings in no way counter the necessity of excising a ruptured spleen, the researchers said, but they do suggest that the loss of the organ is more than a mere “inconvenience,” as it has often been depicted, and could help explain previous reports showing an enhanced risk of early death among people who have undergone splenectomies.

In one study that appeared in The Lancet in 1977, for example, researchers compared a group of 740 American veterans of World War II who had had their spleens removed as a result of battle injuries with a similar size sample of veterans who had suffered other war injuries but had kept their spleens. The splenectomized men, the researchers found, were twice as likely to die of cardiovascular disease as were the veterans in the control group. All of which means that despleening should be diligently guarded against, particularly among our little sports warriors, perhaps through the wearing of appropriate protective gear.

Researchers cite other cases in which organs were presumed to be so dispensable that they could be removed “prophylactically”  often with unfortunate outcomes. In recent years, for example, many older women undergoing hysterectomies have been advised to have their healthy ovaries removed at the same time, the rationale being: if you are past your childbearing years, why hang on to reproductive organs that might turn cancerous and kill you? Yet follow-up surveys have shown that women who underwent elective ovariectomy had a heightened risk of dying during a given study period, were more susceptible to heart disease and lung cancer and were twice as likely to develop Parkinson’s disease compared with women who had kept their ovaries. “Evolution has an edge on us,” Dr. Nahrendorf said. “I would be very careful about saying, ‘You don’t need this organ, get rid of it.’ ”

Another reason to esteem the spleen  a purplish, fist-size, five-ounce organ in the upper left quadrant of the abdominal cavity, just behind the stomach and under the diaphragm  is its illustrious medical and poetic history. Galen considered the spleen to be a source of one of the four bodily humors, specifically the black bile associated with irritable, melancholic cranks. In his poem, “Spleen,” Charles Baudelaire describes a young narrator so weary and despondent, unresponsive even to beautiful women and jesting men, that it is as if the “green waters of Lethe” fills his veins.