Demographic characteristics of participants.

* Borderline serous tumors are considered in the non-cancer category in this study due to the non-invasiveness of these tumors.

Bacterial concentration of each swab sample and DNA extraction controls as measured by broad range 16S rRNA gene PCR.

* p-value < 0.001, paired t-test, comparing each sample type with Fallopian tube/ovarian surface (FTO) samples. PG= Paracolic gutter; LP=Laparoscopic port.

Diversity of identified bacterial species.

A. PCA plot of candidate FT microbiota (84 bacterial species). FT (green) samples have more similarities with paracolic gutter (blue) than with cervical (red) samples. B. Shannon diversity plot of 726 bacterial species identified after filtering step #5 in Supplemental Table 3. * p-value < 0.001, paired t-test, comparing between sample types and between cancer versus non-cancer samples within the same sample type. FTO= Fallopian tube/ovarian surface; PG= Paracolic gutter.

Overview of all participants with processing batch, cancer status, menopausal status, and age in relation to FT microbiome taxa. Each column is a patient, and each row is a bacterial species. The top rows indicate the metadata of each sample as denoted by the color coding of batch, cancer status, menopausal status, and age group.

Prevalence of the 84 bacterial species in ovarian cancer versus non-cancer cases. Each number is the percentage of individuals in each category with the presence of each bacterial species. G= Gastrointestinal; O= Oral; V= Vaginal; S= Skin; B= Broadly present.

The bacterial prevalence in FT samples from ovarian cancer patients by histology subtypes (Non-serous versus serous carcinoma). Each number is the percentage of individuals in each category with the presence of each bacterial species.

Summary of samples sequenced.

Bacterial concentration (log10[16S rRNA genes/μl of DNA]) of each sample type and the p-value of each comparison.

Processing steps and result summary after each step.

Comparison of overall and laparotomy cases in the bacterial prevalence in FT samples from ovarian cancer versus non-cancer patients. Each number is the percentage of individuals in each category with the presence of each bacterial species.

The bacterial prevalence in FT samples from non-cancer patients: comparison of laparoscopic/robotic and laparotomy cases. Each number is the percentage of individuals in each category with the presence of each bacterial species.