In the 1980s, the models of the Third and of the Fourth generations of breast implant devices were sequential advances in manufacturing technology, such as elastomer-coated shells that decreased gel-bleed (filler leakage), and a thicker (increased-cohesion) filler gel. Sociologically, the manufacturers of prosthetic breasts then designed and made anatomic models (natural breast) and shaped models (round, tapered) that realistically corresponded with the breast- and body- types of women. The tapered models of breast implant have a uniformly textured surface, which reduces the rotation of the prosthesis within the implant pocket; the round models of breast implant are available in smooth-surface- and textured-surface- types.
The FDA has identified that breast implants may be associated with a rare form of cancer called anaplastic large-cell lymphoma, believed to be associated with chronic bacterial inflammation. Similar ALCL phenomena have been seen with other types of medical implants including vascular access ports, orthopedic hip implants, and jaw (TMJ) implants. As of February 1, 2017, the FDA has received a total of 359 medical device reports of breast-implant-associated ALCL (BIALCL), including 9 deaths. Most cases of breast implant-associated ALCL had implants in for many years prior to the condition, and are usually treated successfully by simple removal of the implant and the capsule surrounding the implant without the need for chemotherapy if no evidence of systemic disease exists. If women with implants present with delayed swelling or fluid collection, cytologic studies and test for a marker "CD30" are suggested. The American Society of Plastic Surgery (ASPS) states, "CD30 is the main diagnostic test that must be performed on the seroma fluid as routine pathology or H&E staining can frequently miss the diagnosis."  Diagnosis and treatment of breast implant associated ALCL now follows standardized guidelines established by the National Comprehensive Cancer Network.