Discussion
Thymolipomas, a type of mediastinal tumor that consists of mature
adipose and thymic tissue, are exceedingly rare and arise in the thymus
gland. They make up 1.1% of all solid mediastinal tumors and do not
exhibit any gender preferences (3). Thymolipomas are characterized by
the presence of abundant mature fat, which separates the thymic tissue
component, with no evidence of atypia or mitotic activity. Although most
of these tumors are clinically quiescent, they can grow to significant
sizes and present clinical symptoms such as compression of the lower
respiratory tree, resulting in breathlessness, coughing, chest
discomfort, and upper respiratory tract infection. (2) Furthermore, it
can lead to cardiac compression and subsequently, chronic heart failure.
(4) The radiologic characteristics have the ability to resemble various
conditions, such as cardiomegaly, pericardial effusion, pleural tumors,
pericardial tumors, and basal atelectasis (5, 6).
Thymolipoma has been found to have associations with chronic lymphocytic
leukemia, myasthenia gravis, aplastic anemia, hyperthyroidism, and
Hodgkin’s disease in certain cases (7). In our scenario, there was no
relationship established between this presenting case and the tumors
mentioned earlier.
The CT scan is typically the preferred diagnostic modality. The
consideration of thymolipoma diagnosis should be taken into account when
evaluating the accuracy of an anterior mediastinal mass characterized by
fatty tissue containing soft tissue streaks, which signify islands of
normal thymic components, along with contralateral displacement of the
mediastinum on CT scans. (8, 9) A similar finding was observed in the CT
scan outlined in this case report. Teratoma, lipoma, lipomatosis, and
liposarcoma are potential differential diagnoses that should be
considered. (3) There have been reported cases of thymolipoma in
different age groups. (1, 2, 6, 8, 9, 10) Thymolipomas, although
uncommon, should be included in the differential diagnosis, even in
cases of infants with an anterior mediastinal mass. A case of this type
of tumor occurring in a 6-month-old boy has been reported. (11) Thymic
tumors, specifically thymoma, are rarely found outside the mediastinum
(12, 13), but the occurrence of thymolipoma in the lung or other
mediastinal structures, excluding the thymus, has not been recorded. The
considerable dimensions of the tumor in our patient presented
considerable obstacles in determining the precise location or origin of
the mass before the operation.
Surgical excision is the recommended treatment for thymolipoma, as it is
curative and eliminates the need for long-term follow-up for a benign
tumor. No cases of recurrence, metastasis, or mortality have been
reported.