Lymphoma of the cervix invading the uterine body with distant lymphadenopathy: MRI and FDG-PET/CT findings

Abstract

Primary cervical lymphoma is a rare extranodal manifestation of non-Hodgkin lymphoma and may clinically and radiographically mimic primary cervical carcinoma. Involvement of the uterine body is even more uncommon and may further complicate diagnosis. We report the case of an 89-year-old woman who presented with heavy vaginal bleeding and was found to have diffuse large B-cell lymphoma (DLBCL) of the cervix with direct invasion into the uterine body and hypermetabolic pelvic, mediastinal, and supraclavicular lymphadenopathy. Multimodality imaging, including computed tomography (CT), magnetic resonance imaging (MRI), and fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT), demonstrated a markedly enlarged, hypermetabolic cervical mass with disruption of the normal three-zone cervical anatomy, preservation of the endocervical canal and smooth ectocervical contour, and marked restricted diffusion–features suggestive of cervical lymphoma rather than carcinoma. The patient was treated with palliative pelvic radiation for hemostasis followed by R-mini-CHOP chemotherapy (a dose-reduced regimen consisting of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) due to advanced age and frailty, resulting in a marked anatomic and metabolic response. This case highlights key MRI features that help differentiate cervical lymphoma from carcinoma and underscores the importance of tissue diagnosis to guide appropriate systemic therapy. Distinguishing cervical lymphoma from cervical carcinoma is clinically important, as treatment approaches differ substantially; cervical carcinoma is often managed surgically in early stages, whereas cervical lymphoma is treated primarily with systemic chemotherapy due to its inherently systemic nature.

Introduction

Primary lymphoma of the female genital tract is uncommon, accounting for less than 1% of extranodal lymphomas [[1], [2], [3]]. Within this group, involvement of the cervix and uterus is rare, and primary cervical lymphoma is particularly unusual [1,4]. Patients often present with nonspecific symptoms such as abnormal vaginal bleeding, pelvic pain, or a bulky cervical mass, frequently mimicking more common gynecologic malignancies, including cervical carcinoma [1,4].

Diagnosis can be challenging because cervical lymphoma often appears as a solid, infiltrative mass on CT. However, MRI, with superior soft tissue characterization, can reveal features suggestive of lymphoma, including preservation of the endocervical canal and ectocervical contour, relatively homogeneous or mildly heterogeneous T2 signal, and marked diffusion restriction [[5], [6], [7]]. FDG-PET/CT is valuable for staging, as nodal disease beyond the pelvis may be present at diagnosis [6]. Given the rarity of this entity, detailed case descriptions remain important for improving recognition and management. We describe a case of cervical DLBCL with uterine body invasion and distant lymphadenopathy, emphasizing multimodality imaging findings and treatment response.

Case report

An 89-year-old woman (G5P5), menopausal since age 48, presented with one month of heavy vaginal bleeding, saturating approximately 10 pads per day. Associated symptoms included lightheadedness, fatigue, pelvic pain, nausea, and decreased appetite. Family history was notable for gastric cancer in her mother and breast cancer in her sister.

Pelvic examination revealed a smooth but markedly enlarged and firm cervix with dark blood at the external os. Differential considerations included cervical carcinoma, endometrial carcinoma, and lymphoma. Examination under anesthesia with cervical biopsies and loop electrosurgical excision procedure was performed.

CT of the abdomen and pelvis demonstrated a 10.1 × 10.5 × 10.2 cm mass involving the entire cervix, with possible extension into the lower uterine segment. The endometrial canal, containing air from a recent biopsy, was displaced anteriorly by posterior myometrial invasion measuring 5.2 × 3.6 × 4.1 cm (Fig. 1). A mildly enlarged left external iliac lymph node measuring 1.1 × 1.3 cm was present (Fig. 2). No ascites or peritoneal masses were identified. The ovaries appeared normal.

Fig. 1.

Sagittal CT image with intravenous contrast demonstrates a large, well-circumscribed mass centered in the uterine cervix, possibly extending into the posterior uterine body (black arrows). The endometrial stripe is displaced anteriorly by posterior myometrial invasion (red arrow). The endometrium contains air due to recent biopsy.

Fig. 2.

Axial CT image demonstrates a large cervical mass (long horizontal arrow) and a mildly enlarged left external iliac node (short vertical arrow).

MRI of the pelvis demonstrated diffuse enlargement of the cervix with loss of the normal three-zone cervical anatomy. A large mass replaced the entire cervix, extended into the posterior uterine body, and appeared mildly hyperintense on T2-weighted (T2W) imaging. The normal inner low–T2 stromal ring and outer intermediate–T2 stroma were completely replaced by abnormal, heterogeneous high T2 signal. The endocervical canal demonstrated preserved high T2 signal, and the ectocervical contour remained smooth despite marked cervical expansion. The infiltrative mass in the posterior body of the uterus displaced the endometrium anteriorly (Fig. 3).

Fig. 3.

Sagittal T2W MRI demonstrates a T2-hyperintense mass replacing the entire cervix with marked, smooth cervical enlargement and loss of normal three-zone anatomy (pink stars). The mass extends into the posterior uterine body (blue star). The ectocervical contour remains smooth. The endocervical canal (yellow arrow) and endometrium (black arrow) are preserved.

Following administration of 8 mL of intravenous gadobutrol (Gadavist; Bayer, Leverkusen, Germany), T1-weighted (T1W) fat-saturated images demonstrated diffuse, heterogeneous enhancement of the cervical mass, while the endocervical canal remained preserved and hypointense (Fig. 4A, B). No cystic change or tumor necrosis was identified. Diffusion-weighted imaging (DWI) demonstrated marked diffusion restriction, with the cervical mass appearing hyperintense on DWI and correspondingly hypointense on the apparent diffusion coefficient (ADC) map (Fig. 5A, B), consistent with high tumor cellularity.

Fig. 4.

(A) Axial precontrast T1W MRI demonstrates a T1-hypointense mass replacing the entire cervix (green arrow) with marked cervical expansion. (B) Axial postcontrast T1W MRI demonstrates diffuse, heterogeneous enhancement of the cervical mass (long arrow). The hypointense endocervical canal is preserved (short arrow).

Fig. 5.

(A) DWI MRI demonstrates a large cervical mass with pronounced diffusion restriction (arrow). (B) Corresponding ADC map demonstrates low signal intensity, consistent with restricted diffusion (arrow).

FDG-PET/CT revealed intense hypermetabolism of the cervical mass, with a maximum standardized uptake value (SUVmax) of 35.2, extending into the uterus (Fig. 6A). A left external iliac lymph node measuring 1.2 cm demonstrated marked hypermetabolism SUVmax of 25.2 (Fig. 6B). Additional mildly hypermetabolic mediastinal and left supraclavicular lymph nodes were present, with SUVmax values ranging from 2.5 to 3.9 (Fig. 7A, B). The spleen was normal, and no osseous lesions were identified.

Fig. 6.

(A) Coronal FDG-PET/CT demonstrates an intensely hypermetabolic mass involving the markedly enlarged cervix (long arrow) with extension into the uterus (short arrow) and left external iliac lymphadenopathy (arrowhead). (B) Axial FDG-PET/CT demonstrates an intensely hypermetabolic cervical mass (black arrow) with associated hypermetabolic left external iliac lymphadenopathy (green arrow).

Fig. 7.

(A) Axial FDG-PET/CT demonstrates multiple mildly hypermetabolic mediastinal lymph nodes (short and long arrows). (B) Axial FDG-PET/CT demonstrates mildly hypermetabolic left supraclavicular subcentimeter lymph nodes (arrows).

Pathology

Histologic examination demonstrated diffuse effacement of the cervical stroma by sheets of large atypical lymphoid cells, consistent with diffuse large B-cell lymphoma (DLBCL) according to the World Health Organization Classification of Tumours of Haematolymphoid Neoplasms, 5th edition (2022). The neoplastic cells exhibited vesicular chromatin, prominent nucleoli, frequent mitotic figures, and numerous apoptotic bodies. Scattered tingible body macrophages were present, producing a characteristic starry-sky appearance (Fig. 8).

Fig. 8.

Hematoxylin and eosin–stained histologic section demonstrates diffuse replacement of normal cervical tissue architecture by a monotonous population of large atypical lymphoid cells with high nuclear-to-cytoplasmic ratios, vesicular chromatin, and prominent nucleoli (original magnification × 400).

Immunohistochemical analysis showed diffuse positivity for CD20 and expression of CD10, consistent with a germinal center B-cell subtype. BCL2 was positive, and the Ki-67 proliferation index was approximately 95%, indicating a high proliferative rate. Fluorescence in situ hybridization demonstrated no MYC rearrangement, excluding Burkitt lymphoma and high-grade B-cell lymphoma with MYC rearrangement. Bone marrow biopsy was negative for lymphomatous involvement. Overall findings were consistent with stage III-IV cervical DLBCL.

The patient underwent palliative pelvic radiation therapy (1480 cGy in 4 fractions) for hemostasis, followed by six cycles of R-mini-CHOP chemotherapy. Follow-up FDG-PET/CT performed three months after treatment initiation demonstrated marked reduction in both the size and metabolic activity of the cervical mass, resolution of uterine involvement, and normalization of pelvic and distant lymphadenopathy.

Discussion

Primary cervical lymphoma is exceedingly rare, representing a small fraction of extranodal lymphomas and less than 0.5% of cervical malignancies [[1], [2], [3], [4]]. DLBCL is the most common histologic subtype [1,2]. Direct invasion into the uterine body, as demonstrated in this case, has been reported only sporadically [4,8,9].

Patients commonly present with abnormal vaginal bleeding, pelvic pain, or a bulky cervical mass—features indistinguishable from cervical carcinoma [1,4]. Unlike epithelial malignancies, ulceration or exophytic growth is uncommon.

Imaging plays a critical role in differentiating cervical carcinoma from lymphoma, with MRI providing superior assessment of cervical masses compared to CT and ultrasound. CT typically demonstrates a large, relatively homogeneous soft-tissue mass without significant necrosis [5,6].

MRI, with its superior soft-tissue resolution, provides the most useful distinguishing features for cervical lesions. On MRI, the normal cervix demonstrates a three-zone anatomy: the inner zone (cervical mucosa and endocervical canal) is hyperintense on T2-weighted imaging; the middle fibromuscular stroma is hypointense and contiguous with the uterine junctional zone; and the outer zone shows intermediate signal intensity continuous with the myometrium [12]. MRI features of cervical lymphoma include disruption of the three-zone anatomy with diffuse stromal replacement with preservation of cervical shape, endocervical canal, and smooth ectocervical contour, even in bulky disease. Lymphoma often appears relatively homogeneous and mildly hyperintense on T2W imaging with much less necrosis than cervical carcinoma. Following contrast, lymphoma shows diffuse, relatively homogeneous enhancement, whereas carcinoma typically demonstrates heterogeneous enhancement with necrotic components. DWI can provide additional differentiation. Lymphoma usually shows diffuse, homogeneous, marked diffusion restriction with very low ADC values. Carcinoma typically demonstrates heterogeneous hyperintensity on DWI with low ADC signal in dense tumor areas but higher ADC in necrotic regions, resulting in heterogeneity. Carcinomas are typically focal, asymmetric, and irregularly marginated, whereas lymphomas are diffuse, symmetric, and smooth-contoured [[5], [6], [7]]. This case also demonstrates lymphoma extending into the body of the uterus with similar T2 hyperintensity as the cervical mass, unlike uterine fibroids, which are typically dark on T2W imaging.

FDG-PET/CT is essential for staging and assessing treatment response, as high-grade lymphomas such as DLBCL typically show intense FDG uptake [6]. Although SUV values can overlap with cervical carcinoma, high-grade lymphomas generally exhibit markedly higher FDG uptake, whereas cervical carcinoma usually demonstrates lower FDG avidity. When combined with MRI findings, particularly the presence of non-regional lymph nodes outside the typical nodal stations for cervical cancer, FDG-PET/CT can provide valuable diagnostic clues suggesting lymphoma.

DLBCL of germinal center subtype demonstrates high proliferative activity and typically responds well to systemic chemoimmunotherapy [[10], [11], [12]]. Unlike cervical carcinoma, surgery is generally not indicated. Radiation therapy may be used for bleeding control or consolidation. The excellent metabolic and anatomic response in this elderly patient highlights the chemosensitivity of DLBCL, even with bulky disease and distant nodal involvement.

Conclusion

Primary cervical DLBCL is a rare malignancy that can closely mimic cervical carcinoma. Multimodality imaging, particularly MRI and FDG-PET/CT, provides important diagnostic clues. MRI features such as preservation of the endocervical canal, smooth ectocervical contour, mild T2 hyperintensity with relatively homogeneous signal, disruption of the normal three-zone cervical anatomy, and marked diffusion restriction are highly suggestive of cervical lymphoma rather than carcinoma. PET/CT typically shows intense FDG uptake. Definitive diagnosis requires tissue sampling. Recognition of these imaging features may help avoid unnecessary surgery, enable timely initiation of systemic therapy, and guide treatment planning.

Patient consent

Written informed consent has been obtained from the patient for publication of the case report.