8. International Congress on Leukemia Lymphoma Myeloma, 21 - 22 Mayıs 2021, sa.40, ss.57-58
Free light chain escape is a rare phenomenon seen in 3% of multiple myeloma patients [1]. It is characterized by rise of involved free light chain levels
without involvement the heavy chain component. It often accompanies
extramedullary disease progression[2] or rapid renal impairment[3]. Here we
present 3 multiple myeloma cases with free light chain escape and a review
of the literature. Case A: 52-year-old female patient, who has no known
comorbid conditions, undergoes an operation after a tarsal bone fracture
in September 2019 and applies to our clinic after the pathology result is
compatible with plasmacytoma. IgGλ paraproteinemia and multiple bone
lesions are detected and is considered to be R-ISS stage III and treatment
is started immediately with weekly bortezomib + cyclophosphamide +
dexamethasone (VCD). When she came for the 15th day of the first course
it was observed that her general condition deteriorated; anemia, hypercalcemia, and a high creatinine level compatible with acute kidney damage is
detected. At the same time, free λ light chain escape is detected. The patient
is hospitalized and 1 volume plasma exchange is performed 4 times every
other day. In our patient, a 40% free λ reduction was achieved with 4 sessions
of plasma exchange. This data appears to be consistent with the Mayo Clinic
data, where free λ reduction of 36.6–93.3% was observed with a median of 8
sessions (4 to 23) of plasma exchange [4]. Case B: A 46-year-old male patient
was evaluated in June 2010 with complaints of low back pain and fatigue
and IgAλ paraproteinemia was detected. He had anemia and diffuse bone
involvement and diagnosed with multiple myeloma R-ISS: I. The patient has
a history of treatment with VCD, autologous stem cell transplantation (in
2011 and 2018), lenalidomide use has been followed up with pomalidomide
treatment since July 2019, he applied to the orthopedic clinic due to back
pain in July 2020. Magnetic resonance imaging with T2-weighted images
revealed an extramedullary mass lesion with significant compression of the
spinal cord at C7-T1-T2 and free chain escape is simultaneously detected.
Patient underwent allogeneic stem cell transplant(ASCT) after radiotherapy
and remission induction. Case C: 56-year-old female patient is referred with
mild anemia and hypercalcemia and diagnosed with IgGκ multiple myeloma
R-ISS: II. She received high dose chemotherapy with autologous stem cell
support after achieving partial response with four courses of VCD. Relapsed
after 8 months and received lenalidomide+dexamethasone (LenDex) with
no response. Carfilzomib is added to the treatment and she progressed with
many cervical lymph nodes and left pleural effusion. Light chain escape has
been detected. She underwent ASCT after remission induction. Our cases
show that in during the treatment of myeloma, a clone that may be selected
which can lead to light chain escape and disease progression. Also light
chain escape can accompany extramedullary/extraosseous disease progression or rapid renal impairment as suggested by literature. It has also been
put forward that serum free light chain follow-up during treatment could be
useful in identifying this phenomenon [3]. We suggest surveying free light
chain levels in addition to intact immunoglobulin levels and serum protein
electrophoresis during the course of treatment of myeloma patients.