While most patients with widespread parenchymal lung metastases are symptomatic, the following case report describes a relatively asymptomatic individual with metastases arising from a primary uterine leiomyoma.
The patient is a 48 year old female with type 2 diabetes mellitus who was referred from an outside clinic for further work-up of a cough, positive tuberculin skin test and abnormal chest x-ray (CXR). She denied any associated symptoms, recent travel, or ill contacts.The patient had a history of menorrhagia that resolved after a total abdominal hysterectomy five years ago. She was taking an oral hypoglycemic and denied any drug allergies, bad habits, or significant family history. She immigrated from Mexico ten years ago and has lived in Los Angeles since.The patient was afebrile and hemodynamically stable. She was a well appearing, mildly obese female with normal cardiovascular and pulmonary exams. She had an abdominal surgical scar from the prior hysterectomy.Laboratory studies were only remarkable for a mild peripheral eosinophilia and transaminitis. The patient had three negative sputum samples for acid-fast bacilli.The CXR revealed multiple pulmonary nodules bilaterally of various sizes. Computerized tomography (CT) scan of the chest demonstrated multiple well circumscribed pulmonary masses/nodules in bilateral lung fields, suggesting metastatic disease. The largest lung nodule measured 7.0 cm x 3.5 cm x 5.5 cm in the right lower lobe; no mediastinal or hilar adenopathy was present. The patient had normal spirometry.The CT guided biopsy of the right lower lobe lung mass revealed a smooth muscle tumor with benign features: estrogen receptor (ER) and progesterone receptor (PR) were positive and a low mitotic index was present. The prior hysterectomy specimen demonstrated the presence of intravenous leiomyomatosis.DISCUSSION: Three types of smooth muscle tumors exist in Martin1’s classification system: leiomyomatosis, metastatic leiomyoma, and multiple fibroleiomyomatous hamartomas. Leiomyomatosis occurs exclusively in women with uterine leiomyomas and is further subdivided into benign metastasizing leiomyoma, lymphangiomyomatosis (lymphangioleiomyomatosis), leiomyomatosis peritoneali disseminata, and intravenous leiomyomatosis.Birch-Hirschfield2 describes intravenous leiomyomatosis as a uterine tumor with benign-appearing smooth muscle within veins or lymphatics which can enter the inferior vena cava, heart, and lung. Benign metastasizing leiomyoma is described by Steiner3 and others as a well-differentiated tumor composed of smooth muscle cells and dense connective tissue which can also travel to the lung. Canzonieri4 believes the two are “the same pathological entity with different clinical features.”In other case reports of pulmonary metastases secondary to leiomyomatosis, patients often have no pulmonary symptoms and have nodules detected incidentally. Martin1 and Matsumoto5 report two such cases.The prognosis of leiomyomatosis with pulmonary metastases is good as patients often live years after initial diagnoses, as can be seen from Table 1
Characteristics of Patients with Leiomyomatosis and Pulmonary MetastasesAuthorAge of Pt (yrs) at time pulm mets* detectedTime of hysterectomy (years prior to detection of pulm mets)Treatment of pulm metsFollow-upMartin1(1983)4614Bilateral BSOAlive at 9 monthsMulvany9(1994)283Resection of lung massAlive, 5 yrs post-opCanzonieri4(1994) (Case 1)466Resection of recurrent pelvic massAlive, 3 yrs post-opCanzonieri4(1994) (Case 2)460Resection of RML for increase in size of pulm mets 20 years after initial detection of pulm metsAlive 3 yrs post-op with slight enlargement of pulm nodulesClement12(1998) (Case 2)448UnknownAlive 7 yrs after detection lung metsKullo7(1999)5212 (concurrent diagnosis: mass in IVC/RA)Megestrol acetateAlive at 6 yrsMatsumoto5(2001)580TAH/BSO Chemo Thoracotomy five yrs later for increasing pulm metsUnknownCheng (2003)485NoneAlive at 2 months after detection of lung mets*
pulm mets: pulmonary metastases. One prognostic factor is the patient’s hormonal status. Idelson10 and Horstmann11 found that postmenopausal women and women in later stages of pregnancy do better than their counterparts.There are no standard treatment regimens for this disease. It is generally accepted that hysterectomy and bilateral salpingo-oophorectomy be performed to remove the primary tumor and decrease estrogen and progesterone levels. Martin1 and Matsumoto5 found that the pulmonary lesions remained stable in size after hysterectomy/bilateral salpingo-oophorectomy. Kullo7 report using megestrol as a hormonal agent to treat these hormone sensitive tumors. Surgical resection is feasible if the pulmonary lesions are localized.
Leiomyomatosis can metastasize and cause asymptomatic bilateral pulmonary nodules. Although the prognosis of patients with lung involvement is good, these individuals should be followed closely to detect changes in symptoms, radiologic findings, or pulmonary function tests as significant changes may warrant treatment.
G. Cheng, None.