Oligocentric castleman disease: Clinical characteristics and surgical outcomes from a single-centre retrospective study

Abstract Oligocentric Castleman Disease (OCD) is a unique subtype of Castleman disease (CD). Some reports suggest that the clinical features of OCD are more akin to those of UCD, and that patients are consequently more likely to benefit from local treatment rather than the systemic therapy typical of iMCD. However, there is a notable paucity of research pertaining to this subject. To address this, we performed a retrospective, single-centre analysis of 100 CD patients (63 UCD, 37 OCD) to describe their clinical characteristics, treatment, and outcomes. The UCD group had more hyaline vascular pathology (90.5% vs. 62.2%, p=0.001), while OCD showed more mixed pathology (27.0% vs. 6.3%, p=0.004). OCD cases had higher CRP and ESR levels (p=0.007 and p=0.003). OCD group demonstrated a significantly poorer PFS compared to the UCD group (P = 0.0067). A Complete Response (CR) rate of 86.7% was achieved with debulking surgery alone; however, of note, PFS was not improved with the addition of systemic therapy. Within this cohort, factors significantly associated with an inferior PFS were the PC-CD subtype, non-contiguous involvement, involvement ≥3 regions, infradiaphragmatic disease, not achieving a CR to initial treatment, and elevated inflammatory markers (ESR, CRP, or IL-6). To explore this further, we stratified the OCD cohort into asymptomatic and high-inflammation subgroups. This revealed a stark difference in PFS between the two (P =0.00039). Moreover, compared with the asymptomatic subgroup, patients in the high-inflammation subgroup were older and had a significantly higher prevalence of both the PC-CD subtype and non-contiguous disease. In conclusion, debulking surgery represents a viable therapeutic strategy for patients with OCD, and our findings suggest that routine adjuvant chemotherapy may be unnecessary. Nevertheless, factors associated with a hyper-inflammatory state—such as the PC-CD subtype and a greater number of involved nodal regions—are strongly predictive of recurrence. These high-risk features therefore require careful consideration in treatment planning, and further investigation into novel therapeutic strategies for this patient subgroup is clearly warranted.