Median survival time (MST) for dogs with splenic hemangiosarcoma (HSA) after splenectomy alone is 19–86 days, rising to 117–277 days with adjuvant treatment.Journal of the…

Splenectomy without chemotherapy yields an MST of 42–86 days across multiple reports.Journal of Vete… The 2026 AAHA Oncology Guidelines summarize this as 1.5–3 months.AAHA Clinical G… For dogs with incidentally detected, nonruptured splenic masses (a subset with less advanced disease at diagnosis), splenectomy-alone MST was 110 days for those ultimately diagnosed with malignancy, and 132 days specifically for those with HSA, with a 1-year survival rate of 16.7%.Journal of the…

Adjuvant doxorubicin-based chemotherapy extends MST to 139–179 days in dogs with stage I–II disease.Journal of Vete… The AAHA guidelines cite an MST of approximately 3–6 months with adjuvant chemotherapy.AAHA Clinical G… In a stage I–II cohort receiving anthracycline-based protocols, MST was 154 days; dogs who received metronomic chemotherapy following anthracyclines achieved an MST of 338 days, and those receiving metronomic chemotherapy alone achieved 225 days — differences that were not statistically significant between groups.Veterinary and… The overall MST across all adjuvant treatment groups in that cohort was 200 days.Veterinary and…

For stage II disease specifically, splenectomy plus an anthracycline/lomustine alternating protocol produced an MST of 158 days and a 1-year survival rate of 16%. Dogs with a low mitotic score (<11 mitoses/10 hpf) had a significantly longer MST of 292 days and a 1-year survival rate of 42%, compared to 212 days for a mitotic score of 11–20 and 116 days for a score >20.Journal of the…

For stage III (metastatic) disease, prognosis is substantially worse. Overall MST after splenectomy was 40 days without adjuvant treatment, 58 days with metronomic chemotherapy, and 140 days with maximum-tolerated-dose (MTD) doxorubicin-based chemotherapy — MTD was significantly superior to metronomic chemotherapy (p = 0.023), though at the cost of significantly higher treatment-related adverse events.Veterinary and…

Carboplatin is an alternative to doxorubicin when the latter is contraindicated, producing an MST of 160 days versus 139 days for doxorubicin-based protocols in stage I–II dogs — a difference that was not statistically significant.Journal of Vete…

Timing of chemotherapy initiation is prognostically important. Starting adjuvant chemotherapy within 21 days of splenectomy is associated with an MST of 238 days, compared to 146 days when chemotherapy is delayed beyond 21 days (p < 0.001).Veterinary and… After chemotherapy is discontinued, the mean interval to death is 63 days (median 31 days), reflecting rapid progression of metastatic disease once treatment stops.Journal of the…

SettingMST1-Year SurvivalKey Caveat
Splenectomy alone42–86 daysAcross multiple reports Journal of Vete…
Splenectomy alone (incidental nonruptured mass, HSA)132 days16.7%Less advanced presentation Journal of the…
Adjuvant doxorubicin-based (stage I–II)139–179 days<16%Standard of care Journal of Vete…
Adjuvant anthracycline (stage I–II)154 daysNo significant difference vs. metronomic Veterinary and…
Adjuvant metronomic (stage I–II)225 daysNo significant difference vs. anthracycline Veterinary and…
Stage II, anthracycline/lomustine alternating158 days16%Mitotic score strongly prognostic Journal of the…
Stage II, low mitotic score (<11/10 hpf)292 days42%Subset of above Journal of the…
Stage III, MTD doxorubicin-based140 daysHigher adverse event rate vs. metronomic Veterinary and…
Stage III, metronomic chemotherapy58 daysInferior to MTD (p = 0.023) Veterinary and…
Stage III, splenectomy only40 daysShortest outcome in stage III cohort Veterinary and…
Adjuvant carboplatin (stage I–II)160 daysAlternative when doxorubicin contraindicated Journal of Vete…
Chemotherapy started ≤21 days post-op238 daysvs. 146 days if >21 days (p < 0.001) Veterinary and…

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What is the median survival time for dogs with splenic… | VetChamp