Successful Treatment of Concurrent Follicular Lymphoma and Triple-Negative Breast Cancer Using Rituximab Plus Nab-Paclitaxel and Cisplatin: A Case Report and Literature Review

Abstract

Background: Co-occurrence of breast cancer and non-Hodgkin's lymphoma is a rare condition with diagnostic and therapeutic challenges. The coexistence of follicular lymphoma (FL) and triple-negative breast cancer (TNBC) has not been described previously.

Case presentation: A 46-year-old woman, already suffering a history of untreated, advanced-stage, high tumor burden FL, was admitted for a rapidly progressing right breast mass. Ultrasonography showed an 8.3 × 3.6 × 4.1 cm fungating mass in the right breast with enlarged lymph nodes (LNs) in bilateral axillae. PET-CT demonstrated increased ¹⁸F- FDG activity in right breast mass, LNs on both sides of the diaphragm, enlarged spleen, and bone marrow. Biopsy of the right breast mass revealed TNBC. The patient underwent neoadjuvant therapy with R-CHOP and achieved partial response of breast tumor. However, TNBC progressed after three cycles of R-CHOP. According to the next-generation sequencing (NGS) assay on breast mass showing a homologous recombination repair (HRR) deficiency (HRD) score of 72, the neoadjuvant regimen was changed to rituximab plus nab-paclitaxel and cisplatin (R-TP) and resulted in significant tumor regression. The patient then underwent right mastectomy with an axillary LN dissection. After the surgery, she was regularly monitored and given adjuvant therapy with R-TP and radiotherapy.

Conclusion: The coexistence of FL and HRD-positive TNBC poses diagnostic and treatment challenges. Well-founded neoadjuvant strategy based on multidisciplinary team (MDT) discussion and NGS warranted a good outcome in this case.

Keywords: HRD; MDT; case report; follicular lymphoma; multiple primary malignancies; neoadjuvant therapy; triple-negative breast cancer.

Figure 1

Timeline of this case report.

Figure 2

Whole-body PET-CT before (A) and after (B) neoadjuvant therapy. After treatment, the right breast mass (red arrows) significantly decreased in size. Bilateral cervical (Orange arrows), bilateral axillary (green arrows), mediastinal (purple arrows), cardiophrenic (yellow arrows), intraabdominal, intrapelvic and bilateral inguinal (black arrows) LNs decreased in both size and ¹⁸F-FDG uptake. A significant decrease in size and ¹⁸F-FDG uptake was also detected in spleen (blue arrows).

Figure 3

Histopathological and immunostaining examination of TNBC and FL. (A) Hematoxylin and eosin (H&E) staining of right breast specimen showing invasive ductal carcinoma. Magnification, × 400. Right breast specimen immunostaining negative for HER-2 (B), positive for P53 (C) and with a Ki-67 index of 70% (D). Magnification, × 400. (E) H&E staining of right axillary lymph nodes suggesting lymphoma infiltration. Magnification, × 100. Lymphoid follicles immunostaining positive for CD20 (F), CD10 (G), and BCL-2 (H), suggesting FL. Magnification, × 100. H&E staining (I) and AE1/AE3 immunostaining (J) of right axillary lymph node suggesting TNBC metastases. Magnification, × 100. (K) H&E staining of bone marrow specimen showing FL infiltration. Magnification, × 400. (L) Bone marrow specimen immunostaining positive for CD20. Magnification, × 400.

Figure 4

Axial CT of the breast (red arrow) before neoadjuvant therapy (A). The right breast mass decreased from 8.5×6.7 cm to 4.9×5.6 cm (red arrow) after two-cycle of R-CHOP (B), rapidly increased to 7.4×8.7 cm (red arrow) after three-cycle of R-CHOP (C), and decreased to 3.9×3.7 cm (red arrow) after R-TP (D). The corresponding photos of the right breast mass before neoadjuvant therapy (E), after two-cycle of R-CHOP (F), after three-cycle of R-CHOP (G), and after R-TP (H).