Macrodystrophia Lipomatosa Extending Into the Abdominal Wall and Breast: A Case Report

Background Macrodystrophia lipomatosa is a rare nonhereditary congenital gigantism, characterized by overgrowth of mesenchymal and bro-adipose tissue, affecting one or more digits of the extremities. Here, we report a rare case of macrodystrophia lipomatosa of the entire right lower limb with extension of hypertrophied fatty tissue into the abdominal wall and breast. examination muscles presented fat showed no for after


Abstract
Background Macrodystrophia lipomatosa is a rare nonhereditary congenital gigantism, characterized by overgrowth of mesenchymal and bro-adipose tissue, affecting one or more digits of the extremities. Here, we report a rare case of macrodystrophia lipomatosa of the entire right lower limb with extension of hypertrophied fatty tissue into the abdominal wall and breast.

Case presentation
A 32 years old woman was born with abnormally elongated and thickened right leg, and the condition aggravated gradually. The disease was multiple, including the right leg, right abdominal wall, and the left breast were also involved. The patient mainly complained that she was unable to walk but with the knee exed. Physical examination revealed that the elongation and thickening was proportional to the left leg, and the involved joints were malformed and dysfunction. X-ray and Computed tomography angiography (CTA) showed the bones and vessels were elongated and thickened, and the joints were hypertrophic and swollen. Amputation, volume reduction and liposuction was performed on the lesions. Histological examination could see abnormal bro-fatty tissue hyperplasia, the adipocytes were invasive, and part of muscles presented fat degeneration. The lesions showed no recurrence for one year after surgery.

Conclusion
After reviewing the literature of the macrodystrophia lipomatosa, we believed that our case was rare because the hypertrophied fatty tissue extended into the abdominal wall and breast, which was different from former studies and had not been documented worldwide. This novel case will further deepens the understanding of this disease, and will be useful for clinicians in diagnosing it.

Background
Macrodystrophia lipomatosa is a rare nonhereditary developmental malformation that mainly affects bro-adipose tissue manifesting as a form of gigantism affecting one or more digits of the hand or foot [1,2] . In 1925, it was rst described by Feriz as localized gigantism of the lower limb [3] . In 1960, the de nition of this disease was further expanded to include the upper extremity by Golding [4] . Fat deposition in subcutaneous tissues, muscles as well as nerves is the characteristic feature of macrodystrophia lipomatosa [5] . Localized gigantism often has no symptoms and present with cosmetic problems [6] , but as the lesions continue to grow, it may cause secondary osteoarthritis and compression of neurovascular structures. To date, there has only been three reported cases of macrodystrophia lipomatosa involving an entire limb [7][8][9] . And only two cases in which abdominal wall involvement was recorded [8,10] . In our patient, the lesions involved not only the entire right lower limb, but also the right abdominal wall and left breast, which was different from former studies and had not been documented worldwide. And it is the reason we wish to report this case.

Case Presentation
A 32 years old woman was born with abnormally elongated and thickened right leg, and the condition aggravated gradually. Because of the heavy long leg and abnormal joints, the patient was unable to walk normally but with the knee exed. Including the right leg, the right abdominal wall, and the left breast were also involved without palpable mass. There was no related family history. The height and weight were 155cm and 87kg, respectively. We found the elongation and thickening was proportional to the left leg, and the involved joints were malformed and dysfunction (Tab.1, Fig.1). X-ray and Computed tomography angiography CTA were done preoperatively, as well as postoperative histological examination. X-ray showed that all segments of right leg are obviously enlarged, pelvis is de ected, right femur, tibia and bula are thickened, elongated and curved, osseous prominences could be seen on their ends. Tarsals and joint spaces are obscured. The ends of metacarpus and phalanges are thickened with rough borders, some joint cavities are narrowed (Fig.2). CTA showed that the vessels of right leg are smooth but abnormally elongated and thickened, without malformed vessel cluster. Cortex of femur, bula and tibia is rough with hypertrophy, osseous prominences could be seen on the proximal ends, and the patella could not be showed. Bones of right foot are irregular, with obscured joints. Muscles of right leg are atrophied with obviously thicken adipose tissue (Fig.3). Amputation, volume reduction and liposuction was performed on the lesions. And no adverse events were observed post-operation. The extremely thickened subcutaneous adipose tissue and many thickened vessels could be seen in operation, and part of muscles present fat degeneration. Light microscope showed bro-adipose tissue hyperplasia, which was same as the left breast and right abdominal wall. Part of the muscles were in ltrated by adipocytes, with intramuscular fatty hyperplasia, muscle ber degeneration and loss of striation (Fig.4). In summary, the case was diagnosed as Macrodystrophia lipomatosa, which extend into the abdominal wall and breast. The lesions showed no recurrence for one year after surgery. And the patient was satis ed with the result. Discussion And Conclusions Unilateral macromelia could be seen in many cases such as lymphedema lymphangioma, neurofibromatosis, Klippel-Trenaunay-Weber syndrome, and macrodystrophia lipomatosa. In general, the clinical history and a thorough physical examination can help distinguish these entities. Lymphedema begins from the distal ends, and gradually involves the proximal part, with thickening of skin and sunken edema [11] . Lymphangioma is a congenital benign tumor consisting lymph ducts with proliferative endothelia and brous tissue [12] . Neurofibromatosis is characterized by a positive family history and cafe-au-lait spots of skin. An enlarged, tortuous nerve studded by soft-tissue nodules could be checked in plexiform neuro broma [13] . Klippel-Trenaunay-Weber syndrome could be diagnosed according to its characteristic cutaneous capillary hemangiomas and varicose veins [14] . The above diseases could cause thickening of local or total unilateral limb but elongation of limb.
According to clinical presentation this case is most similar with macrodystrophia lipomatosa. Benign bro-fatty in ltration involving the soft tissues of the distal arm or leg is the clinical characteristic of macrodystrophia lipomatosa, with associated dactylomegaly of the associated digits. Macrodactyly initiated shortly after birth and were associated with a high incidence of anomalies including syndactyly, polydactyly, and clinodactyly. Unilateral median nerve distribution of the hands with multiple adjacent digits is more often, while a single digit could be involved, sometimes might be noted on the medial digits of the foot [15] . Histopathological characteristic is bro-fatty tissue hyperplasia which is also similar to this patient's. However, in the involved leg of our case, both elongation and thickening were proportional to the left leg, and such extensive and huge lesion is rarely seen in former literatures. In addition, the abdominal wall and breast were also involved, which is different from former studies.
Histopathological examination of this case could see abnormal bro-fatty tissue hyperplasia, the adipocytes were invasive, and part of muscles presented fat degeneration, which is also similar to congenital in ltrating lipomatosis (CIL) , a rare congenital disease initiating from infant [16] . Slavin et al.
initially described CIL in 1983 [17] . In 1987, De Rosa et al [18] . listed the main characteristics of CIL, including (1)  Ethics approval and consent to participate The ethical approval and documentation for a case report was waived by the Ethical Committee of the Tongji Medical College of Huazhong University of Science and Technology.

Consent for publication
Written informed consent was obtained from the patient for the publication of this case report and any accompanying images.

Competing interests
The authors declare that they have no competing interests. The left leg is normal. All segments of right leg is obviously thickened and elongated, joints are malformed and dysfunction, right lower abdomen wall is bulged, and the left breast is enlarged.