From the Indiana University School of Medicine (Drs. Hagman, Winer-Muram, Meyer, and Jennings), Indianapolis; and Richard L. Roudebush Veteran Affairs Medical Center (Dr. Winer-Muram), Indianapolis, IN.
Correspondence to: Helen T. Winer-Muram, MD, Richard L. Roudebush Veterans Affairs Medical Center, Department of Radiology, 1481 West 10th St, Indianapolis IN 46202; e-mail: firstname.lastname@example.org
Intrathoracic splenosis is a rare diagnosis that is usually
made following an invasive procedure. Although radiographic and CT
findings are nonspecific, these findings combined with a history of
splenic injury should suggest the possibility of thisdiagnosis. We
present a patient with intrathoracic splenosis diagnosed on the basis
of a technetium Tc 99m heat-damaged RBC scan following false-negative
technetium Tc 99m sulfur colloid scan results.
splenosis is a rare diagnosis that is usually made following an
invasive procedure. Although radiographic and CT findings are
nonspecific, these findings combined with a history of splenic injury
should suggest the possibility of this diagnosis. We present a patient
with intrathoracic splenosis diagnosed on the basis of a technetium Tc
99m (99mTc) heat-damaged RBC scan following
false-negative 99mTc sulfur colloid (SC) scan
A 52-year-old, HIV-positive man was involved in a motor vehicle
accident in 1983 and underwent emergent splenectomy. A routine
peripheral blood smear obtained in 1997 revealed a few Howell-Jolly
bodies. Chest radiographs obtained in January 1999 showed healed left
rib fractures and also several nodular opacities in the lower left
hemithorax. Chest CT demonstrated multiple pleural-based nodules,
measuring up to 2 cm in diameter, at the posterolateral base of the
left hemithorax and on the left hemidiaphragm (Fig 1
). Residual splenic tissue was noted at the left upper quadrant of the
A follow-up CT in October 1999 showed no change in the appearance of
the nodules. Given the patient’s history, the possibility of
intrathoracic splenosis was considered and a
99mTc SC scan was performed. Residual splenic
tissue was again identified in the left upper abdomen, but no splenic
tissue was seen in the thorax. Because of the negative
99mTc SC results and the presence of Howell-Jolly
bodies in the peripheral blood smear, intrathoracic splenosis was
However, serial chest radiographs and CT scans during the following
year did not demonstrate any growth or alteration of the pleural-based
nodules, and the possibility of intrathoracic splenosis was
reconsidered. A 99mTc heat-damaged RBC scan was
performed (Fig 2
). The scan revealed multiple areas of increased activity in the left
lower hemithorax, confirming the diagnosis of intrathoracic splenosis.
Splenosis is the autotransplantation of splenic tissue to ectopic
sites, usually as the result of penetrating or blunt traumatic injury
to the spleen. It most frequently involves the peritoneal cavity. While
serosal implants are most common, splenosis has been reported in the
retroperitoneum and liver.1In rare cases, presence of
splenic tissue within the pulmonary parenchyma has been reported when
injury to the lung had occurred along with injury to the spleen.
Rarely, splenic tissue may gain access into the thorax either from a
diaphragmatic tear or through diaphragmatic foramina, and seed the
pleural space. Fewer than 30 cases have been reported in the
literature; in most instances, the diagnosis was made only after
However, intrathoracic splenosis is usually asymptomatic. Moreover,
radiographic and CT findings associated with this disorder are
nonspecific, and several alternative diagnoses exist. These include
lymphoma, mesothelioma, invasive thymoma, and metastatic disease, as
well as localized fibrous tumor of the pleura or pleural
plaques.3The concern that these findings might represent
malignancy may subject the patient to unneeded follow-up or diagnostic
procedures. In addition to the risks associated with surgery or biopsy,
removal of thoracic splenic tissue in a patient without functioning
abdominal splenic tissue may render the patient asplenic, and increase
the risk for infection.4
Scintigraphy with indium In 111-labeled platelets,
99mTc SC, and 99mTc
heat-damaged RBCs all are capable of demonstrating splenosis because
they are sequestered by splenic tissue. However, use of
99mTc heat-damaged RBCs is preferred because of
reduced uptake by normal liver tissue, resulting in improved
target-to-background ratio.5A case has been reported in
which a 99mTc heat-damaged RBC scan depicted additional
foci of splenosis that were not demonstrated on a
99mTc SC scan.6 Our case is unique
in that intrathoracic splenosis was seen on the
99mTc heat-damaged RBC scan following
false-negative 99mTc SC scan results.
Scintigraphy with 99mTc heat-damaged RBCs is not
only more sensitive than 99mTc SC, but is also
superior to the peripheral blood smear. Howell-Jolly bodies represent
nuclear material within the RBC, and are normally retained by the
spleen. Their presence on a peripheral blood smear indicates functional
asplenism. However, other patients with uptake in residual splenic
tissue have also been shown to have Howell-Jolly bodies, presumably due
to the inability of this tissue to function normally.5
Although rare, the diagnosis of intrathoracic splenosis should be
considered in any patient with pleural-based nodules in the left
hemithorax with a history of thoracoabdominal trauma and splenectomy or
splenic injury. Noninvasive confirmation of the diagnosis using
99mTc heat-damaged RBC scintigraphy can spare
patients additional follow-up imaging and/or invasive procedures. This
case demonstrates that reliance on either a negative
99mTc SC scan finding or the presence of
Howell-Jolly bodies on a peripheral blood smear can result in a missed
diagnosis. 99mTc heat-damaged RBC imaging should
be considered the modality of choice to diagnose splenosis.
Abbreviation: SC = sulfur colloid
Performed at the Richard L. Roudebush Veteran Affairs Medical Center,
Become a CHEST member and receive a FREE subscription as a benefit of membership.
Individuals can purchase this article on ScienceDirect.
Individuals can purchase a subscription to the journal.
Individuals can purchase a subscription to the journal or buy individual articles.
Learn more about membership or Purchase a Full Subscription.
Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.
Some tools below are only available to our subscribers or users with an online account.
Download citation file:
Web of Science® Times Cited: 16
Customize your page view by dragging & repositioning the boxes below.
Enter your username and email address. We'll send you a reminder to the email address on record.
Athens and Shibboleth are access management services that provide single sign-on to protected resources. They replace the multiple user names and passwords necessary to access subscription-based content with a single user name and password that can be entered once per session. It operates independently of a user's location or IP address. If your institution uses Athens or Shibboleth authentication, please contact your site administrator to receive your user name and password.