Patient presented with a 2-month history of painful left leg swelling. Past medical history was unremarkable. Physical examination showed a painful soft-tissue mass in the left leg. There were neither any other systemic symptoms nor lymphadenopathy. Laboratory tests were normal.
Anteroposterior radiograph showed an osteolytic lesion with a moth-eaten appearance involving medullary cavity and cortex in proximal metadiaphysis of left tibia (Fig. 1). MR imaging demonstrated bone marrow replacement in proximal metadiaphysis of left tibia with adjacent soft-tissue mass and permeated cortical bone (Fig. 2). Thoracic, abdominal and pelvic CT showed a soft-tissue right breast mass (Fig. 3). There was neither abnormal lymphadenopathy nor visceral involvement on CT. Mediolateral oblique mammogram showed a mass with spiculated margins at 6 o’clock in the right breast at the anterior depth (Fig. 3).
Ultrasound-guided needle core biopsy of the left leg soft-tissue mass demonstrated a high-grade, diffuse, large B-cell lymphoma with CD79a+ and CD 20+ phenotypes (Fig. 4). Bone marrow examination was normal. Ultrasound-guided needle core biopsy of the right breast lesion demonstrated an invasive ductal carcinoma, not otherwise specified (NOS) with E-cadherin positive immunoreactivity (Fig. 5). Axillary surgical assessment was negative.
Multiple primary cancer (MPC) is a specific malignant tumour type, manifesting as more than one primary tumour diagnosed in the same patient, either simultaneously or sequentially [1]. Synchronous multiple primary cancer (SMPC) is defined as two or more tumours occurring within an interval of six months [1, 2]. The reported incidence of SMPC is rare (0, 8%), and it is even less common to observe synchronous solid tumours with a haematological malignancy [2]. Factors that have been suggested as contributing to the development of synchronous malignancies include advanced age of the patient, primary or cancer-related immunological impairment and genetic predisposition to cancer [1-3]. Although it is both impractical and unnecessary to obtain biopsies for every lesion that may appear in a case of MPC [4], awareness of the different biological behaviours between solid tumours and haematologic malignancies should be considered. The treatment choice depends on the tumour location and may involve curative surgical resection of each cancer, radiotherapy, and chemotherapy [2, 3].
Primary bone lymphoma (PBL) is a rare tumour, accounting for less than 1% of all non-Hodgkin lymphomas [5, 6]. Almost all tumours are localised in long bones, and patients present with pain and/or a palpable mass. Patterns of radiographic findings of PBL have varied from near-normal to be predominantly lytic, sclerotic, or mixed lytic-sclerotic. On MR imaging, osseous destruction is variable. It was stated that a tumour with relative preservation of the cortex in the presence of a large extraosseous tumour is likely to be lymphoma. MR imaging may show small linear foci of intermediate or high signal intensity on T2-weighted sequences, penetrating the cortical bone [6].
The patient in our case was found to have an invasive ductal carcinoma-NOS at staging CT.
When one or more suspicious skeletal lesions are discovered in a patient with a known primary malignancy, the lesions are often assumed to represent skeletal involvement by the patient's known malignancy. However, solitary bone metastatic disease at the time of diagnosis of primary breast cancer is distinctly unusual. Bone breast metastases are often osteoblastic, usually involve multiple sites and extension into the adjacent soft tissues is rare. These features are considered useful to distinguish between primary and metastatic malignant lesions [7]. The possibility, although rare, of primary bone disorders like lymphoma should be kept in mind particularly when the marrow bone tumour is surrounded by soft-tissue masses but without extensive cortical destruction.
Synchronous primary bone non-Hodgkin lymphoma and breast invasive ductal carcinoma
On the X-ray of the left lower leg (tibia), there is an abnormal change in bone density, showing disorganized local bone trabecular structure. Part of the cortex is invaded, but the overall continuity is still preserved. An obvious soft tissue mass can be observed. MRI of the same region shows abnormal bone marrow signal, with the tumor protruding into the surrounding soft tissue. The margin of the mass remains relatively clear, accompanied by local soft tissue edema. Overall, there is involvement inside and outside the bone; however, there is no extensive cortical destruction, but rather local soft tissue swelling and formation of a mass. Meanwhile, chest CT indicates a mass lesion in the breast, with pathology confirming invasive ductal carcinoma.
Based on the patient’s advanced age (81 years), clinical presentation of left lower leg pain and swelling, imaging findings (bone destruction with relatively clear margins and cortical preservation, combined with a large soft tissue mass), and pathological results (showing lymphoma cell characteristics), plus histological confirmation of invasive ductal carcinoma in the breast, the diagnosis is:
“Synchronous multiple primary cancers: Invasive ductal carcinoma of the breast combined with primary bone lymphoma.”
If uncertainty remains, further evaluation with PET-CT or more extensive bone marrow and lymph node biopsies can be performed to clarify the extent of the disease and stage it.
Treatment Strategy:
Rehabilitation and Exercise Prescription:
This report is for reference and analysis purposes only and cannot replace face-to-face diagnosis or professional medical advice. Patients should regularly seek medical attention and follow the recommendations of the attending physician.
Synchronous primary bone non-Hodgkin lymphoma and breast invasive ductal carcinoma
